#deciduous forest arthropods

[uncharismatic-fauna]

Open Your Home to the Common House Centipede

A common sight in homes throughout Europe, Asia, the Americas, and Australia the common house centipede (Scutigera coleoptrata) is a medium-sized species of centipede originally from the Mediterranean. In the wild, they prefer grasslands and deciduous forests where they can hide under rocks, logs, or leaf litter. These insects have also adapted well to urban development, and are frequently found in basements, bathrooms, and garages,  as well as gardens and compost piles.

Like other centipedes, the common house centipede has less than 100 legs; in fact, they only have 15 pairs, with the front pair used only for holding prey or fending off threats. All those legs let the common house centipede move up to 0.4 meters per second (1.3 ft/s) over a variety of surfaces, including walls and ceilings. The actual body of S. coleoptrata is only 25 to 35 mm (1.0 to 1.4 in) long, but the antennae are often as long as the body which can give this insect a much larger appearance. However, they can be hard to spot, especially in their natural environments; their tan and dark brown coloration allows them to blend in seamlessly to surrounding vegetation.

Though they pose little threat to humans, house centipedes are predatory. Their primary food source is other arthropods, including cockroaches, silverfish, bed bugs, ticks, ants, and insect larvae. S. coleoptrata is a nocturnal hunter, and uses its long antennae to track scents and tactile information. Their compound eyes, unusual for centipede species, can distinguish daylight and ultraviolet light but is generally used as a secondary sensory organ. When they do find prey, house centipedes inject a venom which can be lethal in smaller organisms, but is largely harmless to larger animals. This makes them important pest controllers. In the wild, house centipedes are the common prey of rodents, amphibians, birds, and other insects.

The mating season for S. coleoptrata begins in the spring, when males and females release pheromones that they can use to find each other. Once located, the male spins a silk pad in which he places his sperm for the female to collect. She then lays fertilized eggs in warm, moist soil in clutches of 60-150. These eggs incubate for about a month, and the young emerge with only four pairs of legs. Over the next three years, juvenile house centipedes molt 7 times, each time gaining new pairs of legs. After they grow their last pair of legs, immature house centipedes molt an additional 3 times, at which time they become sexually mature. If they can avoid predation, individuals can live up to 7 years in the wild.

Conservation status: The common house centipede has not been evaluated by the IUCN, as it is relatively common both in the wild and in urban areas. Although they have been introduced to areas outside their native range, no detrimental environmental effects have been associated with their spread.

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Photos

Joseph Berger

David Paul

Conrad Altman via iNaturalist

[birdstudies]

October 13, 2023 - Ochre-cheeked Spinetail (Synallaxis scutata) Found in parts of Brazil, Bolivia, and Argentina, these spinetails live in and around deciduous forests. Usually foraging in pairs, sometimes with mixed-species flocks, they eat arthropods, mostly picking their prey from the ground. They build large nests with horizontal entrance tubes from twigs, roots, and dry leaves on the ground near tree trunks or logs. Females lay clutches of two or three eggs.

[dougdimmadodo]

March’s Fossil of the Month - Acanthostega (Acanthostega gunnari)

Family: Acanthostega Family (Acanthostegidae)

Time Period: 365 Million Years Ago (Late Devonian)

In life, Acanthostega gunnari would have likely resembled a cross between a lungfish and a salamander, and this isn’t dramatically different to what it really was; Acanthostega was a stem-tetrapod, an early member of the lineage of animals that now contains all reptiles, birds, mammals and amphibians, and is believed to be an example of a key stage in the transition between fleshy-finned fishes and the earliest terrestrial vertebrates. Although it possessed 4 short limbs ending in wide, 8-toed feet, the lack of any clear wrist or ankle joints suggests that Acanthostega likely couldn’t support its weight on land, and this combined with its well-developed pelvic bones implies that it was likely a fully-aquatic animal that primarily relied on a paddle-like fin on its tail to propel it forwards while its limbs were used to steer or possibly to grasp aquatic vegetation. During the late Devonian much of the world (including the area of what is now Greenland where Acanthostega fossils were first discovered) was covered in humid, swampy deciduous forests, and this combined with Acanthostega’s anatomy suggests that it likely inhabited warm, oxygen-poor forest pools, which would also explain one of its more unusual characteristics; in addition to possessing fish-like internal gills (as suggested by the presence of gill arch like structures at the base of its skull), a rudimentary rib cage implies that Acanthostega likely had lungs, allowing it to extract oxygen from water as well as air and thereby survive in shallow, oxygen-starved pools that fishes and larger stem-tetrapods would have struggled to breathe in. The teeth of Acanthostega (which were arranged in two rows and were short and sharp, with two larger fangs on the lower jaw) implies that it was likely carnivorous (possibly feeding on terrestrial arthropods caught from above-water beds of vegetation or the banks of its home pools), and comparisons of the anatomy and mineral makeup of fossils of smaller individuals (believed to be juveniles) with those of larger individuals (which are generally believed to be adults) implies that it grew slowly, possibly taking up to 6 years to reach full maturity (at which point most individuals were around 60cm/23.6 inches long, although the difference in the length of seemingly mature individuals suggests that, as with many fish, adverse environmental conditions could considerably limit Acanthostega’s growth.) Although it is unlikely that Acanthostega or its descendants ever succeeded in colonizing land, it is generally accepted that (having become so well-suited to life in the oxygen-poor pools they inhabited) they had little need to, and as several of Acanthostega’s fellow stem-tetrapods (such as the significantly larger Ichthyostega, which had jointed, six-toed limbs and a more developed rib-cage that likely allowed it to haul itself onto land for prolonged periods like modern mudskippers or seals) are known to have done so, the study of the anatomy and lifestyle of this strange little swamp-dweller can still help to shed light on how the variety of land-dwelling vertebrates seen today came to be. 

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Image Sources

Fossil: https://commons.wikimedia.org/wiki/File:Acanthostega_gunnari.jpg#/media/File:Acanthostega_gunnari.jpg

Restoration: https://www.10tons.dk/acanthostega-gunnari

[todaysbug]

December 30th, 2023

Allegheny Mound Ant (Formica exsectoides)

Distribution: Found in eastern North America, from Nova Scotia down to Georgia, and as far west as Colorado.

Habitat: Prefer forested areas with a relatively open canopy, such as mountain meadows, grasslands and ponderosa pine forests.

Diet: Omnivorous; feed on various types of arthropods as well as aphid honeydew.

Description: Allegheny mound ants form huge mounds that can reach a metre in height and 2 metres in diameter, extending up to a metre down into the ground. They have a complex colony system, with colonies that can persist for decades by replacing their queens as they age with younger, more fertile queens.

These ants are known to kill all vegetation surrounding their mounds, to a distance of 12 to 15 metres, leaving large areas void of live trees and shrubs. They do this by injecting formic acid into the plants. This also leaves large lesions on smaller trees of a variety of species, both deciduous and coniferous. If you see a mound in the distance, don't approach it; this ant species is extremely aggressive, and will swarm and bite if the mound is disturbed.

Images by Gary Alpert.

[thegrandimago]

Taken 2022 31st August, this was a European alder spittle bug (Aphrophora alni) I found on the bus. In Sweden, they occur wherever forest edges, hedgerows, meadows, gardens, and parks are present. Contrary to their name, these spittle bugs don't only feed from alder trees as bushes and trees of different species are also taken, with adults prefer deciduous trees while larvae prefer herbaceous plants. They can be seen from May-October, with their life-cycle beginning in spring hatching from eggs laid close to winter. The nymphs live on the stems and leaves of herbaceous plants protected from exposure by a foam made from plant sap until they've reached their imago stage. Eventually, females will mate and will deposit her eggs on herbaceous plants close to winter, where they overwinter until the following spring starting the cycle over. #animal #animals #djur #natur #naturliv #wildlife #insect #insects #insekt #insekter #nature #spittlebug #spittlebugs #bugs #bug #arthropod #arthropods #invertebrate #invertebrates #truebug #truebugs #insectagram #animalia #arthropoda #insecta #hemiptera #aphrophoridae #aphrophora #aphrophoraalni #europeanalderspittlebug https://www.instagram.com/p/CnSQ_p7Kw_T/?igshid=NGJjMDIxMWI=

[a-dinosaur-a-day]

Nicator

Western Nicator by Charles J. Sharp, CC BY-SA 4.0 

Etymology: Conqueror

First Described By: Hartlaub & Finsch, 1870

Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Inopinaves, Telluraves, Australaves, Eufalconimorphae, Psittacopasserae, Passeriformes, Eupasseres, Passeri, Euoscines, Passerides, Core Passerides, Sylviida, Sylvioidea, Nicatoridae

Referred Species: N. chloris (Western Nicator), N. gularis (Eastern Nicator), N. vireo (Yellow-Throated Nicator)

Status: Extant, Least Concern

Time and Place: Within the last 10,000 years, in the Holocene of the Quaternary 

Nicators are known from Western, Central, and Southeastern Africa 

By Haller1962, CC BY-SA 4.0 

Physical Description: The Nicators are a genus of very distinctive, mid-sized passerines from Africa, ranging from 16 to 23 centimeters in length. The smallest of these species is the Yellow-Throated Nicator, with the Eastern and Western species both being larger than the Yellow-Throated variety and relatively similar in size to each other. They are all fairly olive in color along their backs, with black wings; these wings are spotted yellow. They have long tails, which are also olive green, with yellow tips. Their bellies are white, and they have a variety of differently colored faces. Their bills are grey, medium-length, and thick - with noticeable hooks of the top beak over the lower beak. They also have green and yellow colored bums. 

Western NIcator and Eastern Nicator, by Henrick Grönvold, in the Public Domain 

Diet: The Nicators mainly eat arthropods, especially large butterflies, mantids, beetles, caterpillars, and even sometimes small vertebrates such as frogs and lizards, and even berries.

Behavior: Nicators feed usually alone, maybe sometimes in mated pairs but not often. These are very shy, secretive birds, foraging from the ground to the canopy and hiding among the leaves. They hop and run from branch to branch while looking for prey, sometimes even running through clumps of dry leaves. It occasionally flicks its wings while foraging, holding them open and drooped. They also fly silently in horizontal circuits around the base of a tree, while fanning its tail and flicking its wing - this may startle food in trunks into moving out to be see. The Nicators also will follow hoofed mammals to feed on insects they dredge up. They’ll explore tangled branches, and often pump their tails when excited about the prospect of food. 

Yellow-Throated Nicator by Kunstanstalt v. C. Böhm, in the Public Domain 

These birds make a wide variety of sounds, including far-carrying kwee-kuk-kuk-kuk notes, angry growls, and trilling songs; as well as loud whistling, churring notes, and “chok-chok-chok” calls. Interestingly enough, at least one species has been marked as mimicking other birds. They only sing in well-concealed perches in order to stay safe. None of these birds migrate, so they don’t have much of a migration call in addition to their variety of sounds. 

Yellow-Throated Nicator by Dubi Shapiro, all rights reserved 

Their breeding season varies throughout the year depending on the location where they live, with some populations starting in April, others February, others in December, others in June, others in April, others in August, others in May, and so on. In general, the peak of their breeding season is at the start of the rainy season. The birds are monogamous and are very territorial over their nests, which are flat and triangular. These nests are made of stout stems, leaves, even rootlets. They are usually placed low on the branches, usually not more than one meter high, in dense undergrowth. Usually about one to four eggs, on average just two are laid and incubated by the females. Both parents will feed the nestling young. The chicks hop among the branches after fledging, and stay with the parents (who will alarm them if there is danger approaching) for a little while after that.

Ecosystem: The Nicators live in dense evergreen, jungle, swamp, and semi-deciduous forests, as well as dense shrubbery among the savanna; they can be found in human-made habitats like logged forests, gardens, and plantations. Some are found along coastal forests and lowlands. None are found in particularly high-elevated areas. 

Eastern Nicator by Alan Manson, CC BY-SA 2.0 

Other: These birds are not threatened with extinction, and are very common throughout their ranges. They are even common in protected habitats, including national parks.

Species Differences: The Western Nicator lives in Western Africa, and it has an olive colored head with a yellow ring around its eye. The Eastern Nicator has a black stripe across its head, which is more taupe in color, and it lives along the eastern coast of Africa. The Yellow-Throated Nicator has a black head, with yellow stripes next to the eyes and - most distinctively - a yellow throat. This species lives in central Africa.

~ By Meig Dickson

Sources under the Cut 

Fishpool, L. & Tobias, J. (2019). Eastern Nicator (Nicator gularis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.

Fishpool, L. & Tobias, J. (2019). Western Nicator (Nicator chloris). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.

Fishpool, L. & Tobias, J. (2019). Yellow-throated Nicator (Nicator vireo). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.

Jobling, J. A. 2010. The Helm Dictionary of Scientific Bird Names. Christopher Helm Publishing, A&C Black Publishers Ltd, London.

[gabriel4sam]

Robinsonade: a CodyWan story

Now that the big reveal happened for the @maythe4thfanworks , I can repost my CodyWan here, a little late because things have been so epic those last two weeks, I didn’t even have the energy for that post. 

@wrennette very patiently helped me shaped it and this fic is much better for her help! Thank you so much for your patience!

Under the cut, the fic

It was the swearing that woke Cody; tones of fearful desperation, denial, and anger mingled rolled together.

“ Hang on ,” a voice commanded after the curses, a voice that refused to be ignored, a voice that ordered, infused with power.

“Hang on! I refuse…. You obeyed me so many times Commander, Commander, you need to hang on and that’s an order!”

Cody knew no more.

He floated in a current of nonsense thoughts and sensations. Something was burning nearby. There was something cool and wet against his forehead. There was a voice, following him into his dreams, gibberish that made no sense. Later, he saw his General, tearing open a bacta capsule with his teeth, something wild in his eyes.

Consciousness came back slowly and Cody catalogued what he could perceive. He was on a bunk, he recognized the feeling of the plank pretending to be a mattress under his back. He was hurt, the left part of his torso a pulsing, throbbing mess. He had been looked after, if not totally healed: the tickling of drying bacta was unmistakable.

He opened his eyes.

Over him, the ceiling was grey metal and the lamps were off, but natural light came through a breach in the hull, and he saw lush vegetation beyond. He turned his head. Next to his hip, there was a red head; his General sleeping, half kneeling, half sitting near Cody’s bunk. He tried to move his hand to wake the General but it was too difficult and he passed out again.

Later, Cody would ask Obi-Wan how long he had stayed between death and life, and Obi-Wan would let him see the hull where he had carved little marks: ten long days while Obi-Wan had cared for him, buried Cody’s brothers that had been with them in the shuttle, and foraged for food.

It was the longest Cody had been away from another vod.

The Commander needed another week before strengthening enough for a few steps out of the ship. They went to the cairns his General had built for his vode. Crude, lightsaber-cut stones marked their resting places and the General had carved their names and the marks of their helmets into the stone.

Hollow-head, Pitchlow, Edged and Baddye.

Four more brothers marching away, four more brothers Cody couldn’t help, couldn’t save, for all he was the highest ranked clone in the GAR. They sat on a boulder near the graves a long time and for once, the General stayed blissfully silent while Cody grieved.

After a while, Cody couldn’t watch the cairns anymore and turned his attention on their surroundings. They were in a deciduous forest. The ship had gouged a long trench in the treetops and earth in the pilot’s desperate efforts to transform a crash into a landing.

Poor Baddye. He had been a good pilot and a good brother.

It was almost miraculous the fire from the shuttle hadn’t sparked a forest fire and burned the two survivors.

“It was raining,” Cody suddenly said, “I had forgotten, there was some sort of storm with violent winds and the motors were already hiccupping.”

Obi-Wan nodded and stayed silent.

“Why are we still there? The GAR should already have sent help.”

“The entire nose of the ship suffered tremendous damage in the crash. The beacon itself didn’t survive and the comm system is dead. We’ll need to be patient. They have a lot of systems to search, more than I, in fact, can bear to think of, and this planet is in the middle of nowhere. That’s probably why it was never colonized.”

Stranded. While his brothers were dying by the hundreds.

“I’m ready to go back inside,” Cody said to his General, who immediately propped him up on his shoulders.

That night, for the first time, he refused the gruel the Jedi had made; half mashed rations, half grains the General had forraged, with a side of grilled arthropods found inside some tree stumps.

“How are you sure you aren’t poisoning us?” Cody still found the will to ask.

“The Force is a wonderful way to detect poisons,” said the General, grimacing, “but it isn’t an indication for the taste. Still, we are almost through with our rations and we need proteins.”

After changing Cody’s wound dressing, he asked:

“We don’t know how long we’ll be here. I really would appreciate if you stopped calling me Sir. And I can almost hear the capital of the word General in your head.”

“Those stranded together should be on a first name basis, eh?”

“Something like that.”

“I will accept if you share the bunk with me. This is ridiculous for you to still be sleeping on the floor when you’re the one working every day to procure us water and food.”

Silence, then “And I’m the one they call The Negotiator . Yes, Comm…Cody,” Obi-Wan agreed with a smile.

Cody moved on the bunk to let Obi-Wan join him. It wasn’t designed for two people and Cody choked on a yell when the other man’s elbow touched his side, while trying to find how to place the two of them.

“I’m so sorry. Perhaps I should -” Obi-Wan immediately said.  

“No, let me. Have you never bunked with another Jedi? We did that all the time on Kamino when we were children. Roll on your side.”

Cody settled in the same position, curling up around the other man’s back. Later, he would probably find that a terrible idea but right now, he was exhausted enough that the contact seemed heavenly. The ginger man was warm and solid, the comfort of being skin-to-skin too reassuring to pull away.

Obi-Wan used the Force to spread the thermal blanket from the emergency pack over their bodies.

“Good night, Cody,” were the last words the Commander heard before sleep took him, more restful than the last days.

Time passed. Cody healed. He was strong; mind, body, and soul forged to endure. At first, limping to the graves was the limit of his capabilities, but day after day, he went further. He occupied his days tinkering with the surviving electronics of the ship: everything that had been in the cockpit was a lost cause, but he succeeded in repairing an analyser, cannibalising pieces from other instruments.

“I’m impressed,” Obi-Wan confessed, “It would have been so out of my skill-set we only could have used that thing as the ugliest art assemblage in the galaxy.”

“We used to smuggle some parts out of the training halls,” Cody said, “on Kamino. We tried to assemble them in new, original ways when the lights were out. We wanted something that would be ours.”

“If someone had told you, you would one day use it to avoid food poisoning on a lost world.”

“Not that I don’t believe in the Force as a poison tester, but I remember the green berries you brought once and the symptoms…Oh Stars, the symptoms,” Cody teased, and Obi-Wan laughed, not vexed in the slightest by this allusion to what had not been his finest moment.

Cody began to systematically analyse and categorize everything he could put his hands on, as a way to occupy himself. Flowers, mosses, roots, bark, leaves… He had begun as a way to help their survival but it was a peaceful, interesting activity.

He found some bark they could boil to produce a mild analgesic, some flowers that could help with stomach aches, some hard nuts that cooked inside the ashes of their fire made the tastiest snacks he had ever eaten . . . .

He began to name them, because calling them “ that blue flower that grows next to the stream, not the one in the north, the one in the west, and perfume the middle sized edible grey rodent stew really well ”  or “ the nuts with the indentation in the middle that we found on the tree with the heart-shaped leaves ” quickly became exasperating. His collection grew quickly and he liked working on it in the evenings, while Obi-Wan carved bones into small, useful objects like spoons or new buckles for their belts. He added fishhooks and arrowheads to his carving habits, once he had become good enough to make them small and sharp enough.

The evenings were the most peaceful part of the day, working side by side in front of the fire, a pile of nuts between them.

“You know, when the war is done,” the redhead said one day watching Cody working on analyzing some new roots, “you could perhaps pursue studies in botany.”

“Not sure it’s the place for a clone.”

“You’re a man. And like all sentients, you should have the possibilities to make your own choices. I know the Order is guilty of - ”

“You’re guilty of finding yourself between a rock and a hard place, and making the less terrible choice, sir.”

“Weren’t you supposed to call me Obi-Wan?”

“Not when you’re a self-sacrificing idiot that takes blame for things outside your powers.”

Obi-Wan shook his head in fond exasperation, humpf-ed and grumbled, but accepted the verdict.

They stayed. They hunted, they foraged, they passed the time in training in hand to hand against each other.

“Are you sure you aren’t using the Force?” Cody would ask, his pride bruised, his friend’s thighs around his neck, when he had been thrown on the grass for the tenth time.

“You’re too used to sparring against your brothers. I know I’m not strong enough against you in terms of pure muscle, so I use the fact that I’m more flexible. You need to learn to guard against that.”

“Obi-Wan, I’m pretty sure some of the holovids the men are always smuggling into the barracks start like that!”

The Jedi’s laugh was clear and strong, resonating against Cody. He shifted his hips to be sure his friend wouldn’t feel the effect that sound, and their proximity, had on Cody. Obi-Wan had the grace to pretend he hadn’t noticed. Cody learned fast and ten days after that, he and Obi-Wan were more evenly matched.

“The problem is that you lean too much on your flexibility,” Cody pontificated, sitting on the Jedi’s strong back, blocking his arms and Obi-Wan would groan and protest: “I don’t sound like that!” Cody pressed a little more of his weight on the body under him and the Jedi groaned with a very different tone. Cody was up so fast he might as well have teleported and made a conscious effort to ignore how red Obi-Wan’s face was when he stood.

They stayed and Obi-Wan carved them some wood swords and began to teach Cody everything he could learn of lightsaber dueling without the Force to augment his motions. It was fun, it was sometimes violent, it was a good way to forget for a few hours the number of tallies on the hull of the ship, marking their impromptu three-month vacation. Makashi was Cody’s favorite because balance and footwork were easily acquired talents, not like two meter vertical jumps without a run-up!

They stayed and Obi-Wan carved a big log of wood into a crude table with his lightsaber and engraved it with a spiral of little squares.

“What are you doing?” asked a curious Commander.

“You’ll see,” Obi-Wan answered again and again, when the vod asked again, seeing the Jedi painfully carve some small bones with their crude tools.

One morning, it was ready. He had even used crushed leaves and berries to colour the small bones figures, waiting on the log.

“It’s a game,” Cody understood finally, seeing the bon-...seeing the pieces on the board.

“It’s called the Princes and Thieves game, on a moon named Senali, that I visited long, long ago with my Master. I thought it would help on rainy days. Sit down, I will teach you the rules.”

They stayed. Cody learned old Jedi poems and tried meditation, and Obi-Wan finally learned the story behind his friend’s name and dozens of little anecdotes about his strange childhood on Kamino. They played Princes and Thieves, sometimes late in the night with only the crude moulded candles that Cody made from the tallow of the biggest animals they hunted and talked about everything. Of course, Obi-Wan had seen more planets than Cody, and the ones Cody had seen had often been burning at the time, but Obi-Wan was always happy to learn more about the culture the vode had developed. And if sometimes Obi-Wan’s gaze stayed too long on Cody during those times, the Commander had gotten very good at not noticing.

They stayed. Cody hunted with his blaster first, with a makeshift bow after he ran out of ammunition. He invented small traps to catch tasty rodents. Together, with great difficulty, they searched how to preserve the skins of the animals, because they had a total of three outfits for the two of them and it was becoming an urgent necessity to procure more. Cody tried basketry with a red, strong vine that crawled under trees in the most humid part of the forest. It was a painstaking craft but he had nothing but time and they needed more ways to store things. Even if his baskets were more functional than beautiful and he needed a lot of attempts before succeeding in making the bottom strong enough.

They stayed and they stayed and they stayed, until warm colours touched the trees.

They tried to pretend it wasn’t a problem, probably far too long, huddling together under a pile of furs.

“Do you hear the wind?” Obi-Wan asked one night. It was a stupid question, but a good opening for the discussion they needed to have.

Outside the hull, there was a burst of noise as the wind picked up again.

“If the weather doesn’t get better, we’ll suffer from the cold,” Cody said against Obi-Wan’s back. He saw goosebumps on the back of the redhead’s neck and tried very hard to not ask himself if it was the cold, or his breath that raised them.

“There are limits to what our fire and the furs, or even the Force, can do for us.”

“Perhaps we should move,” Cody proposed after a few seconds, “the hunting is becoming a problem: animals are smarter than us, a lot of them are already hibernating, or have…what’s the term?”

“Migrated?”

“Yes, that. And finding nuts or other plants we can eat, it pushes us to forage farther and farther away every day. I fear soon there will be only bark to help us pass the winter.”

They packed up two days later. All their clothes, dried meat they had prepared on the fire, pouches of nuts and dried berries, the analyzer, and of course, their individual comms that would capture the signal if a Republic ship entered the atmosphere. As another precaution, Obi-Wan carved their intentions and the direction they would take into the hull of the shuttle and then they began their long travel south, sleeping in caves when they could, or against trees, grumbling about the cold and the rain in a nest of humid furs.

They should have left earlier. The days were growing steadily shorter and they needed to stop in the evening when they still had energy, to prepare the camp and gather wood. It was long. Hard. Obi-Wan insisted that The Handmaiden’s third nipple was not a civilized marching song, contrary to the opinions of the bounty hunters who had trained Cody.

Then, after the third day, Obi-Wan completely switched his position and started to song it too, and to add lyrics, dirtier than anything any bounty hunter had ever thought of!

After months at their camp, Cody was more than ready to see other valleys, other sceneries. Even with the lack of comfort, it felt good. Like shedding some part of their past. The further they went from the shuttle, the less he felt like a stranded Commander and the more he simply felt like Cody.  

In the evenings, he observed Obi-Wan patiently carving them a travel set of The Princes and Thieves game. The light of their fire always set red and gold undertones in his beard and hair. With his furs, Obi-Wan looked nothing like the composed Jedi Master he had been on Coruscant. He looked so much more alive, flesh and blood instead of myth and legend.

Cody analyzed the plants he had picked up during the day, finding more and more new species as they went south, or practised his needlework. The first time, it had been only to mend his tunic, but he had discovered that he liked it, like most patient, meticulous tasks. He had a fur quiver for his arrows and he had embroidered it with the markings of his helmet, using large tendons from a big ungulate. Now, he was working on one of their fur blankets, embroidering small starbirds on the border.

They walked a month before being stopped by a sea and then three days more before establishing a more permanent camp in an appropriate place, only ten minutes from a small spring. It fed a little creek, protected from the winds by ochre cliffs covered in small, fragrant bushes. The sea was a beautiful blue, almost as blue as the sky. They pitched their tent and prepared their camp.

“We should name it,” said Obi-Wan, when they had started the fire.

“Winter camp?”

“Not very original.”

“The Handmaiden’s fourth nipple.”

“Certainly not, you miscreant!”

“Villa on the coast?”

And Obi-Wan laughed and immediately carved a sign.

That evening, the Jedi fished in the sea with a makeshift spear while  Cody collected some beautiful sea shells. He would put them on his brothers’ cairns in the spring, if they were still on this world. If they went back to the shuttle camp - he had ideas. The trench made by the ship hadn’t been filled with more than a little grass, perhaps he could plant some of nuts in the spring, see if he could propagate plants they ate. Obi-Wan had talked a little about grafting or stolons but the truth was that the Jedi was no botanist and his knowledge on the subject had quickly run dry. Nevertheless, Cody wouldn’t let that stop him. Yes, he had a lot of ideas.  

After, he  relaxed on the sand, savoring the last rays of sun on his skin and admiring the back muscles of the Jedi. Food was more difficult to obtain than when it only took a trip to the mess, but strangely Obi-Wan had filled out. More sleep, less responsibilities, and physical work that wasn’t being kicked around by Darksiders had done him good.

Obi-Wan came back smiling and laughing, droplets of salt water beading on his naked torso.

Cody’s breath caught in his chest for a few seconds until his body remembered the importance of proper respiration. Obi-Wan stopped a few meters from him, his smile gone, his expression serious. The entire planet seemed to hold its breath. Then he knelt between Cody’s legs. The spear and the fishes were abandoned nearby and with trembling fingers, Obi-Wan touched his friend’s face. They had been on this world for seven months and the GAR regulations, the Code that had regulated their lives seemed far away. Inconsequential, compared to the warmth of Cody inside their nest of furs, to the laughter of Obi-Wan catching their dinner.

Long fingers combed gently through Cody’s hair, longer than it ever had been. Keeping regulation-compliant hair was very low on the list of the Marshall Commander’s priorities.

Cody leaned in. The kiss was no more than a soft sensation, the idea of a kiss more than a kiss. He let a few seconds pass and smiled when Obi-Wan started the second one himself, coming alive against to him, his hands coming up to frame Cody’s face. It stayed slow and soft from kiss to kiss, gentle and tender and too precious to be rushed.

“Dinner!” Obi-Wan suddenly said and Cody’s brain derailed for a second.

“Dinner,” the Jedi persisted, “I want…I want you to be sure. Because that would be so awkward after. Because I wouldn’t…I would never…You’re too important.”

“Dinner,” Cody reassured.

The fishes were almost burned instead of simply cooked as they had great difficulties thinking of something other than the kisses but it was such a satisfying meal.  After dinner, Cody took a walk. He wanted to offer Obi-Wan a moment to change his mind, if necessary. Their friendship had grown so strong over the months that it was already attachment, and going farther would complicate things so much when they went back.

He groaned inwardly to himself and tipped his face up, studying the stars. How was the war? His brothers? The Jedi? Nobody had come. Would they pass all their lives here, together? If he should be stranded with someone that wasn’t his vode, he had very good luck to be with Obi-Wan. They were at the mercy of the first virus nasty enough to defeat Obi-Wan’s Force Healing and always worried about food, but…but it was a good life, together. Some days, he didn’t think about the rest of the galaxy until dusk, when he saw the stars, and he always felt a little guilty about it.

His heart beating wildly, he collected some herbs that refreshed the breath and he made slowly his way back to the camp, munching on them.

Obi-Wan had put more wood in the fire and prepared their nest of furs closer to it than most of the time. He smiled when Cody entered the circle of light and they fell together.

Cody’s heart was ringing and happiness tasted like burnt fish and laughter. Happiness tasted salty on Obi-Wan’s skin, that Cody immediately mapped like he had the surroundings of the shuttle camp.

The galaxy could go on without them.

He would fight for it if a ship came one day, he would do his duty, pick up his blaster and his rank again, and fight, and die, without a whisper of protest.

Nevertheless, between his new lover’s legs, whimpering sweet nothings and sharing deep kisses, he could admit it to himself: Obi-Wan was worth a life on that lost world.

[jerusalemstraycat]

Climate, Flora, Fauna (Founding February week 1)

The main world is essentially an alternate Earth, because I did not want to put in the effort to make it substantially different. It has one sun, one moon, an oxygen-rich atmosphere and water oceans, diverse but familiar (to Earthlings, anyway) climates, and various artificial constructs such as buildings, roads, and bridges (more on that in the following weeks). The most noticeable differences would be in the length of the day and year, both of which are slightly shorter than their Earth equivalents, and the milder seasonal changes, due to the planet’s smaller axial tilt.

The creatures that inhabit this world would also be familiar to us - on a short walk through the woods (say, a deciduous broadleaf forest, common on this planet’s temperate areas as on ours), one may find all five classes of vertebrates as well as innumerable insects and other arthropods, worms in the ground and snails in the water, plants and fungi large and small, and an array of microorganisms. Hike out to rocky, windswept Kaidel, and you will find gulls nesting on the gravel beaches and eating mussels. Take a trip to the sprawling capital city of Masa, and you will find mice skittering in the gutters and finches perching in maple trees. Centuries ago, you may have found leopards and herds of gazelles roaming the plain destined to be engulfed by the glass and concrete of the city.

There are some strange and unfamiliar creatures on this world as well, such as bioluminescent birds and arboreal kangaroo-like animals with prehensile tails, but the real weirdness is offworld, accessible by the portals through which the caras came.

The caras are a species of bipedal sapients, smaller than humans, nicknamed after the flexible carapaces that cover their bodies and give them an insectoid appearance. Several dozen millennia ago, the caras started to arrive through an interdimensional portal system with a pre-existing link on the planet. Where did it come from? Who installed it? Who built the surrounding temple-like structure carved with strange symbols? Nobody knows. However, the caras have a hunch that the portals and the temple share a common origin with their own homeworlds, a system of miniscule and highly arid artificial asteroids orbiting a sunless gas giant. The asteroids resemble large fractal structures, like infinite cathedrals held together with stone bridges between the spires. Whoever constructed the asteroids, temple, and the link between them is long gone, as no other lifeforms exist on the caras’ homeworlds. In the surrounding interstellar space, however, monsters beyond mortal comprehension drift and dream. They cause no problems except to the occasional reckless or unfortunate cara in very specific circumstances (must be in a certain location on certain asteroids facing a certain way at a certain time of day...).

The caras on the planet live alongside the Bura, the native sapient species. They are bipedal relatives of leporids that have spread over most of the world from the steppes where they evolved. The caras form colonies almost exclusively in the arid areas to which they are adapted, while the more cosmopolitan Bura have established themselves just about everywhere else.

[exotic-venom]

(Agkistrodon bilineatus taylori) Taylor's cantil

Habitat: Mainly found in mesquite-grassland, thornforest, & tropical deciduous forest in northeastern Mexico. Most often found away from water, on or near rocky hillsides, w/ abundant limestone outcroppings. Limited to Mexican states of Tamaulipas, San Luis Potosi, & Hidalgo (& maybe eastern Coahuila) & usually at moderate or lower elevations of <600 m. 

Activity and Behavior: Mainly terrestrial, & mainly nocturnal. Preys mainly on available lizards, small mammals, & birds, but often also eats grasshoppers & other arthropods. Sometimes basks in morning sunlight. Ovoviviparous w/ 3-10 young/ litter observed for captured specimens. 

Venom Characteristics: Mainly hemotoxic. Can cause extensive tissue necrosis. Serious human envenomations and deaths have been reported to have been caused by this species

[siva3155]

300+ TOP ECOLOGY Interview Questions and Answers

ECOLOGY Interview Questions for freshers and experienced :-

1. What is Ecology? Ecology is the field of Biology that studies the relations between living beings and between living beings and the environment. 2. What are species? Species is the set of living beings able to cross among themselves generating fertile offspring. This concept however does not apply to individuals of exclusive reproduction and other definitions have been proposed. For example, "species is a set of living beings that evolve in a common manner all of them considered ancestors of the same type in relation to common descendants". 3. What is population? Population is the set of individuals of the same species found in a given place in a given time. 4. What is a community? What is the difference between the concepts of community and population? Community is the set of populations of living beings that live in the same region and interact with each other. In Ecology population is a set whose members (living in a given place in a given time) are part of the same species. Community is a set of populations of different species (living in a given place in a given time). 5. What is the difference between ecological niche and habitat? Ecological niche is the set of peculiar activities, resources, and strategies that a species explores to survive and reproduce. Habitat is the place where the species lives to explore its ecological niche. In other words, it can be said that habitat is the "address" of the species and the ecological niche is the "profession" of the species. 6. What are biotic factors? Biotic factors are the living beings (plants, animals, and microorganisms) that are part of a given environment. Image Diversity: biotic factors 7. What are abiotic factors? Abiotic factors are the nonliving elements that constitute a given environment, like light, temperature, minerals, water, gases, atmospheric pressure, etc. Image Diversity: abiotic factors 8. What is an ecosystem? Ecosystem is a system composed of biotic and abiotic factors in interaction. Image Diversity: ecosystem 9. What is biosphere? Biosphere is the set of all of the ecosystems of the planet. 10. What are autotrophic beings? What are heterotrophic beings? Autotrophic beings are those that can produce their own food, i.e., that make organic material from inorganic compounds. Heterotrophic beings are those that need to incorporate organic material to nourish them. Therefore, heterotrophs depend on the production of the autotrophs.

ECOLOGY Interview Questions 11. What are the processes that autotrophic beings use to produce organic material from inorganic substances? Autotrophic beings make organic material by photosynthesis or by chemosynthesis. There are photosynthetic autotrophs, like plants, and chemosynthetic autotrophs, like some bacteria. 12. What is a biome? Biome is a prevailing ecosystem constituted by similar biotic and abiotic factors present in one or more regions of the planet. 13. What are the major terrestrial biomes? The major terrestrial biomes are tundras, taigas (or boreal forest), temperate forests, tropical forests, grasslands and deserts. 14. What are the typical vegetation and the typical fauna of the tundras? Tundras have vegetation formed mainly by mosses and lichens. In the fauna the dense furred animals, like caribous, musk oxen and polar bears, and migratory birds are found. Biomes - Image Diversity: tundras 15. What are the typical vegetation and the typical fauna of the taigas? Taiga, or the boreal forest, is characterized by coniferous trees, pine forests. There are also mosses, lichens, small bushes, and angiosperms. In the taiga many mammals, like moose, wolves, foxes and rodents, migratory birds and great diversity of insects are found. Biomes - Image Diversity: taigas 16. What are the typical vegetation and the typical fauna of the temperate forests? In the temperate forest, deciduous trees predominate. Mammals are found in great number, like bears and deers. Biomes - Image Diversity: temperate forests 17. What are deciduous trees? Deciduous trees are plants that lose their leaves in a period of the year. In the case of the deciduous of the temperate forest, the fall of the leaves occurs in the autumn. The loss of leaves is a preparation to face the cold months of the winter: roots, stem and branches are more resistant to low temperature and snow than the leaves; without leaves the metabolic rate of the plant is reduced; the decaying fallen leaves help to nourish the soil. Biomes - Image Diversity: deciduous trees 18. What is the typical localization of the tropical forests regarding latitude? Tropical rain forests, like the Amazon forest and the Congo forest, are typically located in low latitude, i.e., in the equatorial and tropical zones. Biomes - Image Diversity: tropical forests 19. What are the typical vegetation and the typical fauna of the tropical forests? In the vegetation of the tropical forests, broad-leafed evergreen trees predominate. On the top of the trees, epiphytes and lianas grow. Many varieties of pteridophytes can be found in these forests. Regarding the fauna, the abundance, and diversity is also great: there are monkeys, rodents, bats, insectivores, felines, reptiles, aves, amphibians, and invertebrates, mainly insects. 20. How can the abundance and diversity of living beings in the tropical forests be explained? The biodiversity of these ecosystems can be explained by the great availability of the main abiotic factors for photosynthesis. Since these factors are abundant, plants can perform maximum photosynthetic activity, living and reproducing easily. With great amount and diversity of producers (autotrophs), the consumers (heterotrophic animals and microorganisms) also have abundant food and a complex food web emerges creating many different ecological niches to be explored. So it is possible the appearing of varied living beings as well as the existence of large populations. 21. Why the tropical forests are also known as stratified forests? In tropical forests, tall trees of several species have their crowns forming a superior layer under which diverse other trees and plants develop forming other inferior layers. From the upper layer to the inferior layers the penetration of light lowers gradually and the exposition to wind and rain, the moisture and the temperature vary. Different compositions of abiotic factor condition the prevailing of different vegetation in each layer. 22. What is the typical vegetation of the grasslands? Grasslands are mainly formed of herbaceous (nonwoody) vegetation: grass, bushes, and small trees. Biomes - Image Diversity: grasslands 23. How are the grasslands of North America and of South America respectively called? The steppe grasslands of North America are called prairies. The grasslands of South America are known as "pampas" (the steppe grassland) and "cerrado" (the savannah grassland). Biomes - Image Diversity: prairies pampas cerrado 24. How are grasslands classified? Grasslands may be classified into steppes and savannahs. In the steppes, the prevailing vegetation is grass, like in the pampas of South America and in the prairies of North America. The fauna is mainly formed by herbivores, like rodents and ungulates. The savannahs present small trees, like for example the Brazilian cerrado or the African savannahs. The fauna is diverse; in the Brazilian cerrado there are animals like emus, lizards, armadillos, jaguars, etc., and many types of insects; the African savannahs are the home of great herbivores and carnivores, like zebras, giraffes, antilopes, lions and leopards. Biomes - Image Diversity: savannah 25. What are the typical vegetation and the typical fauna of the deserts? The predominant fauna of the desertic ecosystems is formed by reptiles, like lizards and snakes, terrestrial arthropods and small rodents. In these areas plants very adapted to dry climate may be found, like the cactus, that are plants that do not have real leaves and thus lose less water, along with grasses and bushes near places where water is available. Biomes - Image Diversity: deserts 26. Which terrestrial vertebrate group is extremely rare in deserts? Amphibians are terrestrial vertebrates extremely rare in desertic environments (although there are few species adapted to this type of ecosystem). Amphibians are rare in deserts because they do not have permeable skin and so they easily lose water by evaporation and desiccate. They also need an aquatic environment to reproduce, since their fecundation is external and their larva is water-dependent. 27. What are plankton, nekton, and benthos? Plankton, nekton, and benthos are the three groups into which aquatic living beings may be divided. The plankton is formed by the algae and small animals that float near the water surface carried by the stream. The nekton is composed of animals that actively swim and dive in water, like fishes, turtles, whales, sharks, etc. The benthos comprehends the animals ecologically linked to the bottom, including many echinoderms, benthonic fishes, crustaceans, mollusks, poriferans and annelids. Biomes - Image Diversity: plankton nekton benthos 28. What are the phytoplankton and the zooplankton? Phytoplankton and zooplankton are divisions of the plankton. The phytoplankton comprehends the autotrophic floating beings: algae and cyanobacteria. The zooplankton is formed by the heterotrophic planktonic beings: protozoans, small crustaceans, cnidarians, larvae, etc. 29. What is the group of aquatic beings composed of large number of photosynthetic beings? A large number of photosynthetic beings is found in the plankton, i.e., in the surface of aquatic ecosystems. This is because light is abundant on the surface. 30. What is the primary energy source for life on earth? The primary energy source for life on earth is the sun. The sun plays the important role of keeping the planet warmed and it is the source of the luminous energy used in photosynthesis. This energy is converted into organic material by the photosynthetic autotrophic beings and consumed by the other living beings. Image Diversity: the sun 31. What is the main means by which autotrophic beings obtain energy? The main means by which autotrophs obtain energy is photosynthesis. (There are also chemosynthetic autotrophs.) Image Diversity: photosynthesis 32. Which is the autotrophic group responsible for the production of most part of the molecular oxygen of earth? Algae and cyanobacteria of the phytoplankton are the organisms that contribute most for the production of molecular oxygen. Image Diversity: phytoplankton 33. In the ecological study of food interactions how are the autotrophic beings called? In Ecology, autotrophic beings are called producers because they synthesize the organic material consumed by the other living beings of an ecosystem. An ecosystem cannot exist without producers. 34. How are the heterotrophic beings divided in the ecological study of food interactions? Heterotrophs are divided into consumers and decomposers. An ecosystem can exist without consumers but it cannot be sustained without decomposers. Without the decomposers, the organic material would accumulate causing environmental degradation and later death of the living beings. 35. What is a food chain? Food chain is the linear not branched sequence in which a living being serves as food for the other, from the producers until the decomposers. Image Diversity: food chain 36. How is energy transferred along a food chain? The energy flux along a food chain is always unidirectional, from the producers to the decomposers. 37. What are tropic levels? How many tropic levels can a food chain have? Tropic levels correspond to positions on a food chain. Therefore, producers always belong to the first tropic level and decomposers to the last tropic level, consumers that eat directly the producers belong to the second tropic level and so on. There is no limit regarding the number of tropic levels on a chain, since many orders of consumers can exist. 38. What are primary consumers? Can food chain present quaternary consumers without having secondary or tertiary consumers? Can a tertiary consumer of one chain be a primary or secondary consumer of another chain? Primary consumers are living beings that eat autotrophic beings, i.e., they eat the producers. Primary consumers always belong to the second tropic level of a chain. A food chain cannot have consumers of superior orders without having the consumer of the inferior orders. A consumer however can participate in several different chains not always belonging to the same consumer order in each of them. 39. What is the difference between the concepts of food chain and food web? The chain concept is a theoretical model to study the energy flux in ecosystems. Actually, in an ecosystem the organisms are part of several interconnected food chains, forming a food web. Therefore, the chain is a theoretical linear sequence and the web is a more realistic representation of nature in which the food chains interconnect forming a web. Image Diversity: food web 40. What are the three main types of tropic pyramids studied in Ecology? The three types of tropic pyramids studied in Ecology are the numeric pyramid, the biomass pyramid, and the energy pyramid. Generally, the variable dimension of the pyramid is the width and the height is always the same for each represented strata of living beings. The width therefore represents the number of individuals, or the total mass of these individuals or the available energy in each tropic level. Image Diversity: tropic pyramids 41. What do numeric pyramids represent? Numeric pyramids represent the number of individuals in each tropic level of a food chain. Image Diversity: numeric pyramids 42. In a numeric pyramid to which tropic level does the base always refer? In a numeric pyramid the base corresponds to the first tropic level, i.e., to the producers. The top level of the pyramid corresponds generally to the last consumer order of the food chain (since the number of individual decomposers, most of them microorganisms, is too large to be represented). Image Diversity: decomposers 43. In a numeric pyramid, is it possible the base to be smaller than the other levels? Since the numeric pyramid represents the quantity of individuals in each trophic level of the food chain, inferior tropic levels with fewer individuals than the superior tropic levels may exist. For example, a single tree can serve as food to millions of insects. 44. In the short range what will happen to the levels above and below a population of secondary consumers of a numeric pyramid if a large number of individuals from this population dies? If an intermediate level of a numeric pyramid has its variable dimension decreased, i.e., if the number of individuals of such level is reduced, the number of individuals of the level below will increase and the number of individuals of the level above will be reduced. That happens because the individuals of the level below will face less predators and the individuals of the level above will have less available food. 45. What do biomass pyramids represent? Biomass pyramids represent the sum of the masses of the individuals that participate in each tropic level of a food chain. Image Diversity: biomass pyramids 46. What is dry mass? When biomasses are compared often, the concept of dry mass is used. The dry mass is the total mass less the water mass of an individual. The total mass is also called fresh mass. To use dry mass instead of fresh mass is utile because among living beings, there are differences related to the proportion of water within their body and such differences can distort the quantitative analysis of incorporated organic material. 47. What do energy pyramids represent? Energy pyramids represent the amount of available energy in each tropic level of the food chain. Image Diversity: energy pyramids 48. Into which type of energy is the light used in photosynthesis transformed. The luminous energy used in photosynthesis is transformed into chemical energy. 49. Can the amount of available energy in a given tropic level to be larger than the available energy in inferior tropic levels? What does that condition means to the conformation of the energy pyramids? A superior tropic level always has less available energy than inferior tropic levels. This is because in each tropic level only a fraction of the organic material of the level below is incorporated into the consumers (into their bodies), the other part is eliminated as waste or is used in the metabolism as energy source. Therefore it is never possible to have energy pyramids with inverted conformation, i.e., with the tip to the bottom and the base to the top. It is also not possible to have superior tropic levels with variable dimension larger than inferior ones. In every energy pyramid, from the base to the top, the size of the variable dimension decreases. 50. What is the gross primary production of an ecosystem? How does GPP relate to photosynthesis? Gross primary production of an ecosystem, or GPP, is the quantity of organic material found in a given area in a given period. Since only autotrophs produce organic material and photosynthesis is the main production process, GPP is a result of the photosynthesis. 51. What are the factors that for influencing photosynthesis also interfere with the gross primary productivity? Mainly water and light, but also mineral salts, temperature, and carbon dioxide are factors that interfere with the gross primary productivity. 52. What are the destinations of the organic material fabricated by the producers? Part of the organic material synthesized by the producers is consumed as energy source for the metabolism of the own producer individual. Other part is incorporated (into the body) and become available to heterotrophic beings of the ecosystem. In each following tropic level part of the organic material is used in the metabolism of the individuals of the level, other part is eliminated as waste and only a fraction is incorporated and become available as food for the following level. 53. What is the formula of the net primary production (NPP)? How does NPP relate to the energy pyramids? Net primary production is the gross primary productivity less the organic material consumed as energy source in the metabolism of the producers: NPP = GPP - (organic material spent in aerobic respiration). It represents the organic material available in the first tropic level. The base of the energy pyramids must represent the NPP and not the GPP since the idea of these pyramids is to show the available energy in each trophic level of the food chain. 54. What are biogeochemical cycles? Biogeochemical cycles are representations of the circulation and recycling of matter in nature. The main biogeochemical cycles studied in Ecology are the water cycle, the carbon cycle, and the nitrogen cycle. 55. What is the respective importance of water, carbon, and nitrogen for the living beings? Water is the main solvent of the living beings and it is necessary practically for all biochemical reactions, including as reagent of photosynthesis. Many properties of water are very important for life. Carbon is the main chemical element of organic molecules; carbon dioxide is also reagent of photosynthesis and product of the energetic metabolism of the living beings. Nitrogen is a fundamental chemical element of amino acids, the building blocks of proteins that in their turn are the main functional molecules of the living beings; nitrogen is also part of the nucleic acid molecules, the basis of reproduction, heredity, and protein synthesis. 56. What is the water cycle? The water cycle represents the circulation and recycling of water in nature. Liquid water on the planet surface is heated by the sun and turns into water vapor that gains the atmosphere. In the atmosphere large volumes of water vapor, form clouds that when cooled precipitate liquid water as rain. Therefore, water comes back to the planet surface and the cycle is completed. As possible steps of the cycle, water may still be stored in subterranean reservatory or under the form of ice in mountains and oceans and it may also be used in the metabolism of living beings, incorporated into the body of the individuals or excreted through urine, feces, and transpiration. Image Diversity: the water cycle 57. Why is the sun the "motor" of the water cycle? The sun can be considered the motor of the water cycle because upon its energy the transformation of liquid water into water vapor depends. Therefore, the sun is the energy source that makes water to circulate in nature. 58. What is the carbon cycle? The carbon cycle represents the circulation and recycling of the chemical element carbon in nature because of the action of living beings. Photosynthetic beings absorb carbon as carbon dioxide available in the atmosphere and the carbon atoms become part of glucose molecules. During the cellular respiration of these beings, part of this organic material is consumed to generate ATP and in this process, carbon dioxide is returned to the atmosphere. Other part is incorporated by the photosynthetic organisms into the molecules that compose their structure. The carbon atoms incorporated into the producers are transferred to the next tropic level and again part is liberated by the cellular respiration of the consumers, part becomes constituent of the consumer body and part is excreted as uric acid or urea (excretes later recycled by decomposer bacteria). Therefore, carbon absorbed by the producers in photosynthesis returns to the atmosphere through cellular respiration along the food chain until the decomposers that also liberate carbon dioxide in their energetic metabolism. Under special conditions in a process, that takes millions of years carbon incorporated into organisms may also constitute fossil fuels stored in deposits under the surface of the planet as fossil fuels burn the carbon atoms return to the atmosphere as carbon dioxide or carbon monoxide. The burning of vegetable fuels, like wood, also returns carbon to the atmosphere. 59. What is the main biological process that consumes carbon dioxide? The main biological process that consumes carbon dioxide is photosynthesis. 60. How is carbon dioxide made by producers and consumers? Carbon dioxide is made by producers and consumers through cellular respiration. 61. What are fossil fuels? Fossil fuels, like oil, gas, and coal, form when organic material is preserved from the complete action of decomposers, generally buried deep and under pressure during millions of years. Under such conditions, the organic material transforms into hydrocarbon fuels. Fossil fuels are natural reservatory of carbon. When oxygen is present, these fuels can be burned and carbon dioxide and carbon monoxide are released to the atmosphere. 62. What is the most abundant form under which nitrogen is found in nature? The most abundant nitrogen-containing molecule found in nature is molecular nitrogen (N2). The air is 80% constituted of molecular nitrogen. 63. What is the nitrogen cycle? The nitrogen cycle represents the circulation and recycling of the chemical element nitrogen in nature. The nitrogen cycle depends on the action of some specialized bacteria. Bacteria of the soil called nitrogen-fixing bacteria present in plant roots absorb molecular nitrogen from the air and liberate nitrogen under the form of ammonia. The decomposition of organic material also produces ammonia. In the soil and roots (mainly of leguminous), a first group of chemosynthetic bacteria called nitrifying bacteria, the nitrosomonas, produces energy consuming ammonia and releasing nitrite (NO2). The second group of nitrifying bacteria, the nitrobacteria, uses nitrite in chemosynthesis releasing nitrate (NO3). In the form of nitrate, nitrogen is then incorporated by the plants to be used as constituent of proteins and nucleic acids and the element then follows along the food chain. Nitrogen returns to the atmosphere by the action of denitrifying bacteria that use nitrogen-containing compounds from the soil and release nitrogen gas (molecular nitrogen). Image Diversity: the nitrogen cycle 64. Why is leguminous crop rotation used in agriculture? Leguminous crop rotation and other crop rotations are used in agriculture because in these plants many bacteria important for the nitrogen cycle live. The leguminous crop rotation (or conjointly with the main crop) helps the soil to become rich in nitrates that then are absorbed by the plants. Green manure, the covering of the soil with grass and leguminous, is a way to improve the fixation of nitrogen and it is an option to avoid chemical fertilizers. 65. What is biodiversity? Biological diversity is the variety of species of living beings of an ecosystem. In ecosystems, more biodiverse, like tropical forests, a great variety of plants, microorganisms, and animals live; in ecosystems less biodiverse, like deserts, there are less variety of living beings. Image Diversity: variety of life on Earth 66. How does biological diversity relate to the characteristics of the abiotic factors of an ecosystem? The availability of abiotic factors, like light, moisture, mineral salts, heat and carbon dioxide, conditions more or less biodiversity of an ecosystem. Photosynthesis depends on water and light, and plants need mineral salts, carbon dioxide, and adequate temperature for their cells to work. In environments where these factors are not restrictive, the synthesis of organic material (by photosynthesis) is maximum, plants and algae can reproduce easier, the population of these beings increases, potential ecological niches multiply and new species emerge. The large mass of producers makes viable the appearing of a diversity of consumers of several orders. In environments with restrictive abiotic factors, like deserts, the producers exist in little number and less diversity, a feature that thus extends to consumers and conditions fewer ecological niches to be explored. 67. How does the vegetal stratification of an ecosystem influence the biological diversity? The vegetal stratification of an ecosystem, like the strata of the Amazon Rainforest, creates vertical layers with peculiar abiotic and biotic factors, dividing the ecosystem into several different environments. Therefore, in the superior layer near the crowns of big trees, the exposition to light, rain, and wind is greater but moisture is lower comparing to the inferior layers. As one goes down the strata, the penetration of light diminishes and moisture increases. Regarding the biotic factors, communities of each stratum present composition, features, food habits, and reproduction strategies, etc., also different. Such variations in the abiotic and biotic factors make the selective pressure upon the living beings also diversified, there are more ecological niches to be explored and more varied beings emerge during the evolutionary process. 68. Despite having a great biodiversity why, is the Amazon Rainforest under risk of desertification? The natural soil of the Amazon Rainforest is not too fertile but it is enriched by the vegetal covering made of leaves and branches that fall from the trees. Deforestation reduces this enrichment. In deforestation zones, the rain falls directly on the ground causing erosion, "washing" large areas (leaching) and contributing to make the soil even less fertile. Besides that, the deforestation disallows the recycling of essential nutrients for plants, like nitrogen. In this manner, those regions and their neighboring regions undergo desertification. Image Diversity: Amazon Rainforest 69. How can a great biological diversity protect an ecosystem from environmental damages? Why are less biodiverse ecosystems under the risk of suffering deep biological harms if submitted to even small changes? In ecosystems with more biodiversity, the food webs and ecological interactions among living beings are more complex and diverse. In these ecosystems, environmental changes can easier be compensated by the multiplicity of available resources, foods, and survival options. In ecosystems with less biodiversity, the individuals are more dependent on some beings that serve them as food and they interact with a small number of different species. In these ecosystems, generally, abiotic factors are restrictive and the species are more specialized to such conditions and more sensitive to environmental changes. Even small environmental harms can cause big disturbances in the equilibrium of the ecosystem. 70. Is monoculture a system that contributes to great biological diversity of an ecosystem? Monoculture means that in a large area a single crop (only one species of plant) is cultivated. Therefore, monoculture does not contribute to the formation of a community with great variety of species in the area. Since there is only a single type of producer the types of consumers that can live in the area are also restricted. 71. What are some economic applications that can be generated by very biodiverse ecosystems? Very biodiverse areas present enormous economic potential. They can be source of raw material for the research and production of medicines, cosmetics, chemical products, and food. They are depository of genetic wealth that can be explored by biotechnology. They are source of species for agriculture. They can also be explored by the ecological tourism. 72. What are the main causes of the loss of the biological diversity nowadays? The biggest dangers to the biological diversity today are fruits of the human action. The main of them is the destruction of habitats caused by the growth of the cities, deforestation, pollution, and fires. The second is the invasion of ecosystems by nonnative species introduced by humans; these species change the equilibrium of ecosystems causing harm. Other big dangers are the predatory hunting and fishing and the global warming. 73. What is inharmonious ecological interaction? Inharmonious, or negative, ecological interaction is that in which at least one of the participating beings is harmed. 74. How are ecological interactions classified? Ecological interactions are classified as intraspecific or interspecific interactions and as harmonious or inharmonious interactions. 75. What are intraspecific and interspecific ecological interactions? Intraspecific ecological interactions are those between individuals of the same species. Interspecific ecological interactions are ecological interactions between individuals of different species. ECOLOGY Questions with Answers 76. What is inharmonious ecological interaction? Inharmonious, or negative, ecological interaction is that in which at least one of the participating beings is harmed. 77. What is harmonious ecological interaction? Harmonious, or positive, ecological interaction is that in which none of the participating beings is harmed. 78. What are the main intraspecific ecological interactions? The main harmonious intraspecific ecological interactions are colonies and societies. The main inharmonious intraspecific ecological interactions are intraspecific competition and cannibalism. Symbiosis and Other Interactions - Image Diversity: colonies animal societies 79. What are colonies and societies? Colonies are functional integrated aggregates formed by individuals of the same species. Colonies are often confounded with a single individual. Examples are the coral reefs, by-the-wind sailors, and filamentous algae. Societies are interactions for labor division and collaboration among individuals of the same species. Human societies are examples of ecological societies; other species, like bees, ants, termites, wolves and dolphins form societies. 80. What is competition? Which type of ecological interaction is competition? Competition is the ecological interaction in which the individuals explore the same ecological niche or their ecological niches partially coincide and therefore competition for the same environmental resources takes place. Competition is harmful for all participating beings and thus it is classified as an inharmonious (negative) ecological interaction. Symbiosis and Other Interactions - Image Diversity: intraspecific competition 81. What is an example of intraspecific competition? Intraspecific competition practically occurs in all species, for example, the competition of humans for a job. 82. Why is cannibalism an inharmonious intraspecific ecological interaction? In cannibalism an individual eat other of the same species (occurs in some insects and arachnids). Since it is an interaction between beings of the same species and at least one of them is harmed (the other is benefited) the classification as inharmonious intraspecific ecological interaction is justified. Symbiosis and Other Interactions - Image Diversity: cannibalism 83. What are the main interspecific ecological interactions? The main harmonious interspecific ecological interactions are protocooperation, mutualism and commensalism. The main inharmonious interspecific ecological interactions are interspecific competition, parasitism, predatism and ammensalism. 84. What is protocooperation? Protocooperation is the ecological interaction in which both participants benefit and that is not obligatory for their survival. Protocooperation is a harmonious (positive) interspecific ecological interaction. Examples of protocooperation are: the action of the spur-winged plover that using its beak eats residuals from crocodile teeth; the removal of ectoparasites from the back of bovines by some birds that eat the parasites; the hermit crab that live inside shells over which sea anemones live (these offer protection to the crab and gain mobility to obtain food). Symbiosis and Other Interactions - Image Diversity: protocooperation 85. What is mutualism? Mutualism is the ecological interaction in which both participants benefit and that is obligatory for their survival. Mutualism is a harmonious (positive) ecological interaction. Mutualism is also known as symbiosis. Examples of mutualism are: the association between microorganisms that digest cellulose and the ruminants or insects within which they live; the lichens, formed by algae or cyanobacteria that make organic material for the fungi and absorb water with their help; nitrifying bacteria of the genus Rhizobium that associated to leguminous offer nitrogen to these plants. Symbiosis and Other Interactions - Image Diversity: mutualism 86. What is commensalism? Commensalism is the ecological interaction in which one individual benefit while the other is not benefited neither harmed. Commensalism is a harmonious (positive) ecological interaction, since none of the participants is harmed. Example of commensalism are the numerous bacteria that live in the skin and in the digestive tube of humans without being pathogenic neither beneficial. They are innocuous bacteria living in commensalism with humans. Symbiosis and Other Interactions - Image Diversity: commensalism 87. What benefits can commensalism offer to a species? Commensalism may involve obtention of food (for example, the innocuous bacteria of the human guts), shelter or support (epiphytes on trees) and transportation (pollen carried by insects or birds). The commensalism that involves obtention of shelter is also called inquilinism. 88. What are some examples of interspecif competition? Examples of interspecific competition are the dispute among vultures, worms, flies, and microorganisms for carrions and the competition between snakes and eagles for rodents. Symbiosis and Other Interactions - Image Diversity: interspecific competition 89. What is parasitism? Parasitism is the ecological interaction in which a being lives at the expense of other. The parasite often does not cause immediate death of the host since it needs the host alive to survive. Parasitism is an inharmonious (negative) interspecific ecological interaction, since although one participant benefit the other is harmed. Symbiosis and Other Interactions - Image Diversity: parasitism 90. What are some examples of parasitism? Classical examples are the parasites of humans (host), like the trypanosome that causes Chagas' disease, the HIV virus (AIDS), the bacteria that causes tuberculosis, the schistosome that causes schistosomiasis, the hookworms, etc. Other examples are tree (host) and parasitic helminths (parasite), dog (host) and lice (parasite), cattle (host) and tick (parasite), etc. 91. What is predatism? Predatism is the ecological interaction in which one individual mutilates or kills other to get food. Predatism is an inharmonious (negative) ecological interaction since one participant is harmed. Symbiosis and Other Interactions - Image Diversity: predatism 92. Is herbivorism a form of predatism? Herbivorism is the form of predatism in which first order consumers feed from producers (plants or algae). For example, birds and fruits, humans and eatable vegetable, etc. (There are proposals to consider the herbivorism of leaves a form of parasitism and the herbivorism of entire plants and seeds a form of predatism). 93. What is ammensalim? Ammensalism is the ecological interaction in which an individual harms other without obtaining benefit. Ammensalism is an inharmonious (negative) ecological interaction since one participant is harmed. (Sometimes it is wrongly said that ammensalism is a form of ecological interaction in which an organism releases in the environment substances that harm another species; this situation is indeed an example of ammensalims but the concept is not restricted to it.) One of the best examples of ammensalism is the one established between humans and other species under extinction due to human actions like habitat devastation by fires, ecological accidents, leisure hunting, etc. Other example is the red tide, proliferation of algae that by intoxication can lead to death of fishes and other animals. 94. What is ecological succession? Ecological succession is the changing sequence of communities that live in a ecosystem during a given time period. Image Diversity: ecological succession 95. What are pioneer species? What is the role of the pioneer species? Pioneer species are those first species that colonize places where previously there were no living beings, like, for example, algae that colonize bare rocks. In general, pioneers species are autotrophs or maintain harmonious ecological interaction with autotrophic beings (like autotrophic bacteria, herbaceous plants, lichens). The pioneer community is formed of species able to survive under hostile environments. The presence of these species modifies the microenvironment generating changes in abiotic and biotic factors of the ecosystem undergoing formation. Therefore, they open way to other species to establish in the place by the creation of new potential ecological niches. 96. What is the difference between primary ecological succession and secondary ecological succession? Primary ecological succession is the changing sequence of communities from the first biological occupation of a place where previously there were no living beings. For example, the colonization and the following succession of communities are in a bare rock. Secondary ecological succession is the changing sequence of communities from the substitution of a community by a new one in a given place. For example, the ecological succession from the invasion of plants and animals are in an abandoned crop or land. 97. What is the climax stage of an ecological succession? The climax stage is the stage of the ecological succession in which the community of an ecosystem becomes stable and does not undergo significant changes. In the climax community practically all ecological niches are explored and the biodiversity is the greater possible. In this stage the biomass, the photosynthesis rate and the cellular respiration reach their maximum levels and thus the net primary production (NPP = organic material made by the producers - organic material consumed in the cellular respiration of the producers) tends to zero. At the climax, the amount of oxygen released by photosynthesis is practically equal to the oxygen consumed by respiration. (This is one more reason why it is wrong to say that the Amazon Rainforest, an ecosystem at climax stage, is "the lung" of the earth. Other reasons are lungs are not producers of oxygen; the algae and cyanobacteria of the phytoplankton are the main producers of the molecular oxygen of the planet.) 98. How do biodiversity, the total number of living beings, and the biomass respectively vary during the ecological succession? Biodiversity, the number of living beings, and the biomass of an ecosystem tend to increase as the succession progresses and they stabilize when the climax stage is reached. At the initial stage of the succession the use of carbon dioxide and the fixation of carbon into the biomass are high, since the total number of living beings in the ecosystem is increasing. At the climax stage, the use of carbon dioxide by photosynthesis equals the production by cellular respiration and the fixation of carbon into the biomass tends to zero. 99. What is a population? In Biology population is a set of individuals of the same species living in a given place and in a given time. Population Ecology - Image Diversity: world human population 100. What is population density? Population density is the relation between the number of individuals of a population and the area or volume they occupy. For example, in 2001 the human population density of the United States (according to the World Bank) was 29,71 inhabitants per square kilometer and China had a population density of 135,41 humans per square kilometer. 101. What is population growth rate? Population growth rate (PGR) is the percent variation between the numbers of individuals in a population in two different times. Therefore, the population growth rate can be positive or negative. 102. How different are the concepts of migration, emigration, and immigration Migration is the moving of individuals of a species from one place to other. Emigration is the migration seen as exit of individuals from one region (to other where they will settle permanently or temporarily). Immigration is the migration seen as the settling in one region (permanently or temporarily) of individuals coming from other region. Therefore, individuals emigrate "from" and immigrate "to". 103. What are the main factors that affect the growth of a population? The main factors that make populations grow are births and immigration. The main factors that make populations decrease are deaths and emigration. 104. What are some examples of migratory animals? Examples of migratory animals are: southern right whales from Antarctica, that procreate in the Brazilian coast; migratory salmons that are born in the river, go to the sea and return to the river to reproduce and die; migratory birds from cold regions that spend the winter in tropical regions; etc. Population Ecology - Image Diversity: migratory animals 116. What is biotic potential? Biotic potential is the capability of growth of a given population under hypothetical optimum conditions, i.e., in an environment without limiting factors to such growth. Under such conditions, the population tends to grow indefinitely. Population Ecology - Image Diversity: biotic potential curve 117. What is the typical shape of a population growth curve? How the biotic potential can be represented in the same graphic? A typical population growth curve (number of individuals x time, linear scale) has sigmoidal shape. There is a short and slow initial growth followed by a fast and longer growth and again a decrease in growth preceding the stabilization or equilibrium stage. The population growth according to the biotic potential curve however is not sigmoidal, it is only crescent and points up to the infinite of the scale (there is not a decreasing stage in any equilibrium). Population Ecology - Image Diversity: population growth curve 118. What is environmental resistance? Environmental resistance is the action of limiting abiotic and biotic factors that disallow the growth of a population, as it would grow according to its biotic potential. Actually, each ecosystem is able to sustain a limited number of individuals of a given species. The environmental resistance is an important concept of population ecology. 119. What are the main limiting factors for the growth of a population? The factors that limit the growth of a population can be divided into biotic factors and abiotic factors. The main abiotic limiting factors are availability of water and light, availability of shelter. The main limiting biotic factors are population density and inharmonious (negative) ecological interactions (competition, predatism, parasitism, ammensalism). 120. How do the availability of water and light and the climate affect the growth of a population? The availability of water and light and the climate are abiotic factors that limit the growth of a population. Since the producers are the responsible for the synthesis of organic material transfered along the food chains of an ecosystem, water and light affect the availability of food and a population cannot grow beyond the number of individuals the environment is able to feed. For example, in the desert, the biomass is relatively small and populations that live in this ecosystem are smaller (comparing to same species in environments with large available biomass). The climate, including the temperature, affects the population growth because excessive change in this factor, as the occurrence of droughts or floods, may cause significant population decline; small climatic changes can also alter the photosynthesis rate and reduce the availability of food in the ecosystem. 121. How do populations of predators and preys vary in predatism? Whenever a predator population increases at the first moment, the prey population tends to decrease. At a second moment, the decrease of the prey population and the bigger population density of predators make the predator population to decrease. The prey population then revert the tendency to decrease and begins to grow. If variations in the size of the populations occur in an unexpected intensity, for example, due to ecological accidents killing many preys, the prey-predator equilibrium is disturbed and both species can be harmed. The existence of the predator sometimes is fundamental for the survival of the prey population, since the absence of predatism favors the proliferation of the preys and, in some cases, when the excessive proliferation creates a population size over the sustenance capacity of the ecosystem, environmental degradation occurs and the entire prey population is destroyed. Population Ecology - Image Diversity: predator x prey curve 122. What is the relation between environmental resistance and the population growth according to the biotic potential curve and the real population growth curve? The difference between the real population growth curve (number of individuals x time) and the population growth according to the biotic potential curve of a given population is a result of the environmental resistance. 123. How different is the growth according to the biotic potential of a viral population from the growth according to the biotic potential of a bacterial population? The growth curve according to the biotic potential of virus and bacteria both present positive exponential pattern. The difference between them is that in each time period bacteria double their population while the viral population multiplies dozen or hundred times. The viral population growth curve thus has more intense growth. This happens because bacteria reproduce by binary division, each cell generating two daughter cells, while each virus replicate generating dozens or even hundreds of new virus. 124. What are age pyramids? Age pyramids are graphical representations in form of superposed rectangles each representing the number of individuals included in age ranges into which a population is divided. Generally, the lower age ranges are represented more to the bottom of the pyramid, always below higher ranges, and the variable dimension that represents the number of individuals is the width (there are age pyramids however, in which the variable dimension is the height). Population Ecology - Image Diversity: age pyramids 125. What are the analyses provided by the study of human age pyramids? The study of human age pyramids can provide the following analysis: Proportion of individuals in economically active age, Proportion of elderly (indicating the quality of the pension and health systems), proportion of children and youth (indicates need for job generation and educational services), reproductive profile (shows the population growth tendency), and postnatal survival rate (indicates quality of the health system, hygiene conditions, nutrition, and poverty), longevity profile etc… It is possible to suppose whether a population belongs to a rich and industrialized society or to a poor country since the patterns of the age pyramids differ according to these conditions. 126. What are the main characteristics of the age pyramids of developed countries? In a stabilized human population, the age pyramid has narrower base since the reproduction rate is not so high. The adult age ranges are generally wider than the infantile ranges showing that in practice there is no population growth. There is a proportionally high number of old individuals meaning that the life quality is elevated and the population has access to health services and good nutrition. These are features of the age pyramids of developed countries. Population Ecology - Image Diversity: france age pyramid 127. What is the typical conformation of the age pyramids of underdeveloped countries? The age pyramids of peripheral countries or underdeveloped countries have characteristics related to the poverty of such populations, with wider base and narrow apex. The base age range if much wider than the other levels showing high birth rate. The levels just above the base may present impressive reduction in poorer populations due to infant mortality. Ranges that represent the youth are also wide showing future pressure on job and habitation needs. The widths of the rectangles diminish as age increases to the apex that represents the elderly, demonstrating difficult life conditions, precarious health services, and low life expectancy. 128. What is pollution? Pollution is the contamination of an ecosystem by factors that are harmful for the equilibrium of its biotic or abiotic constituents. Environmental Issues: pollution 129. Is pollution always caused by humans? In most cases, pollution is caused by the human activity. Other species and some abiotic factors however can also pollute an ecosystem. For example, the red tide is created by proliferation of some algae and the volcano dust is a consequence of the internal activity of the planet. 130. Why waste is considered one of the major environmental issues? The environmental problem concerning waste worsens with the industrial development and the global growth of consumption societies in the XX and XXI centuries, factors that cause the immense volume of residuals produced by humankind in the last decades. The increased waste generation raises the issue about what to do with waste since nature is not able to degrade and resorb with adequate speed and efficiency most part of the residuals. Therefore, the several kinds of waste accumulate, polluting the environment and creating danger to humans and nature. 131. What are the main types of waste? The waste can be classified into many types or fractions, each of them carrying its own different environmental problem: organic waste, recyclable waste, non-recyclable waste, toxic waste, nuclear toxic waste, and space waste. The organic waste is easier resorbed by nature, but the speed and the geographical concentration of its production due to urbanization generate pollution of rivers, lakes, proliferation of disease vectors and environmental degradation of towns. The recyclable waste is composed of residuals that can be reprocessed, used again by humans, like plastics and metals. The problem regarding recyclable waste is that the separation of such material is not culturally diffused and there is not enough social organization to use them; so the recyclable waste is mixed to other wastes increasing even more the volume of waste depositories. The non-recyclable waste is formed of residuals that the technology cannot yet recycle, like ceramics, photographic paper, mirrors, cigarrettes, plasticized papers, etc; this kind of waste in the future may become recyclable waste and should be separated. The toxic waste includes industrial chemical residuals that are harmful for life and the environment, like contaminated medical waste and the domestic waste containing insecticides and medicines; the toxic waste is one of the major environmental problems since it puts the life of humans and other living beings in danger. The nuclear toxic waste is made of materials that release invisible dangerous radiation for many years. The nuclear toxic waste is produced in the extraction of nuclear minerals (like uranium), by nuclear reactors and nuclear plants, in hospitals where Nuclear Medicine is performed and in research centers; although the nuclear waste is often put in armored recipients the risk of accidents is permanent. Space waste is the waste produced by the activity of humans in the space from the second half of the XX century; it consists of inn operant satellites, rocket pieces, and other equipments that remain orbiting the earth or other celestial bodies or even traveling across the space. Environmental Issues: organic waste recyclable waste non-recyclable waste toxic waste nuclear toxic waste 132. What is selective waste collection? Recyclable waste is the waste that can be reprocessed and used again. Waste recycling depends on the separation of the recyclable residuals from non-recyclable ones and on the classification of the recyclable into plastics, metals, papers, etc. The function of the selective waste collection is to ease that separation for the waste to be sorted in the point of origin. Selective collection also helps the creation of environmental conscience in the people that produce the waste. Environmental Issues: selective waste collection 133. What is the cost-benefit relation regarding sewage treatment as a strategy to fight water pollution? To treat sewage is much cheaper for society. The non-treated sewage pollutes rivers, lakes and the sea, being a cause of diseases transmitted through water. For the society, the costs of these diseases are much higher than the cost of the sewage treatment. One of the most economical systems to treat sewage is the aerobic treatment system, reservatories kept much oxygenated for aerobic bacteria to decompose organic material. Environmental Issues: sewage treatment 134. What is eutrophication? Eutrophication is the process of excessive increasing of nutrients, like phosphate and nitrate, in water due to direct deposition of non-treated sewage. The nutrients act as fertilizers leading to abnormal proliferation of aquatic algae. With the exaggerated growth of the alga population, the number of aerobic bacteria that make decomposition of organic material also increases. The proliferation of these bacteria depletes the dissolved oxygen killing fishes and other animals. Besides, the lack of oxygen causes the decomposition to be assumed by anaerobic bacteria. Anaerobes multiply and release hydrogen sulfide that makes water improper to other living beings and with a putrid smell. Environmental Issues: eutrophication 135. What is a biodigester? Biodigester is equipment that produces carbon dioxide, hydrogen sulfide, and fuel gases (biogases) like methane from organic material under decomposition (dung, food waste, sugar cane waste, etc.). The biogas is used in heating, as energy for motors and machines and it has even industrial uses. Biodigesters are widely used in public waste depositories and in rural areas. Besides producing biogas the organic waste can be turned into good quality fertilizer. Environmental Issues: biodigester 136. What are the environmental harms caused by mercury pollution? What are the main sources of mercury pollution? Mercury is a metal that when present in the water of rivers, lakes, and seas contaminates fishes, crustaceans, molluscs and other living beings. The mercury accumulates along the food chain and in each following trophic level; the amount of the metal within the individuals is higher. When humans eat contaminated animals they also became contaminated and severe nervous system injuries may come out. The main sources of mercury pollution are gold mining and the use of derived substances in industry and agriculture. Environmental Issues: mercury pollution 137. Besides mercury which other heavy metals cause toxic pollution? Examples of other heavy metals that cause toxic pollution are lead, cadmium, and chromium. 138. What are persistent organic pollutants (POPs? POPs, or persistent organic pollutants, are toxic substances formed from organic compounds. POPs are made in several industrial processes, like the production of PVC, paper whitened by chlorine, herbicides, insecticides and fungicides, and in the incineration of waste. Examples of POPs are dioxins, furanes, chlordane, DDT, dieldrin, heptachloride, toxaphen and hexachlorbenzene. POPs are toxic and highly harmful since, likewise the heavy metals, they are bioaccumulative, i.e., they are not degraded by the body and accumulate even more in each following trophic level of the food chains. In humans, POPs can cause cancer and nervous, immune, and reproductive impairments. Environmental Issues: persistent organic pollutants 139. Is the upward move of the warm air good or bad for the dispersion of pollutants? The upward move of warm air is a natural method of dispersion of pollutants. The air near the ground is hotter because the sun heats the soil and the soil heats the air nearby. Since it is less dense, the warm air tends to move towards higher and colder strata of the atmosphere. Such movement helps the dispersion of pollutants. 140. Does thermal inversion occur in the winter or in the summer? Pollutant low altitude thermal inversion occurs in the winter. In this period of the year, the sun heats the soil less and the natural upward move of warm air decreases. Therefore, the pollutants form a low altitude layer between the cold air layer near the ground and another layer of warmer air above. The pollutant layer over industrial areas or big urban concentrations reduces the penetration of the sun energy and the air bellow takes an even longer time to warm. Environmental Issues: thermal inversion 141. Why does thermal inversion increases air pollution? Which harms can thermal inversion cause to humans? Thermal inversion confines at low altitude, layer of pollutants that would have been dispersed by the natural upward move of warm air. The solid particles present in the atmosphere cause health problems, like the exacerbation of asthma and other pulmonary diseases, cough, respiratory unease and ocular discharges; later the pollution can also trigger the appearing of cardiovascular and neoplastic diseases. 142. What is the role of the ozone layer for the living beings? Ozone, O3, is a gas of the atmosphere that filters ultraviolet radiation from the sun disallowing most of that radiation of reaching the surface of the planet. Ultraviolet radiation is harmful for living beings because it is a mutagen and can cause cancer (mainly skin cancer), other DNA mutations, and even burns. Environmental Issues: ozone layer 143. What are the main chemical compounds that destroy the ozone layer? The mains chemical compounds that destroy the ozone layer are the CFCs, chlorofluorocarbons, or freons, substances used in the past in refrigerators, airconditioners and spray cans. Chlorofluorocarbons react with ozone in the high atmosphere releasing molecular oxygen and therefore the amount of ozone in the atmosphere is reduced. Other substance that destroys the ozone layer is methyl bromide, used in agricultural insecticides. 144. What is nuclear pollution? Nuclear pollution consists in radiations emanated from atomic nuclei, these radiations are high injurious for the living beings. They can be originated from the extraction of radioactive minerals, nuclear plant reactors, nuclear research centers, hospitals, and medical centers that use radioisotopes, nuclear bomb explosions, or accidents with transportation, handling, or storage of nuclear material. Nuclear materials remain dangerous for many years, contaminating the environment with radiation that can cause cancer, immune impairment, congenital deficiencies, burns, and even death. The damage is proportional to the intensity of the exposition to the radiation. Its persistent feature and high aggression power make nuclear pollution one of the major environmental problems of our time. 145. What is plutonium reprocessing? Why is it a big environmental issue? Plutonium is the highly radioactive chemical element produced from uranium by nuclear plants. Plutonium can be reprocessed and used again in nuclear plants or in other destinations, like the making of nuclear bombs. Plutonium reprocessing nowadays, however, is done only in some countries like France, Russia and Britain and the countries that have nuclear plants, like Japan, Australia, etc., send their atomic waste by ship to those plutonium reprocessing centers. Besides the inherent risks of the storage of nuclear waste, plutonium reprocessing brings the risks of the transport of radioactive material across the oceans. The "nuclear ships" often travel near the coast of many countries posing danger to their populations. Environmental Issues: plutonium reprocessing 146. What is transgenic food? Transgenic beings are animals, microorganisms and plants that contain recombinant DNA, i.e., genes from other plants, microorganisms or animals artificially inserted into their genetic material. Transgenic beings are made for scientific and economic purposes, in this last case with the intention of improving their commercial features. For example, bacteria that produce human insulin are transgenic beings made by biotechnology. The main targets of the transgenic technology are the eatable vegetables, like soy, corn, potato, and tomato. Environmental Issues: transgenic beings 147. Why transgenics are considered a threat to the environmental safety? Transgenic can be dangerous to the entire biosphere since the transfer of genes between species may have immediate and long-term unpredictable consequences. The creation of new species by nature is a slow process, dependent on causal mutations and natural selection, a relatively safe process for the ecological equilibrium. It is impossible to know how the fast and artificial introduction of transgenic beings in nature affects ecosystems. Pathogenic agents may be involuntarily created in laboratories, spreading unknown diseases; transgenic species may uncontrollably proliferate destroying ecological interactions that have taken thousands of years to be established; the ingestion of transgenic food also has unpredictable effects. 148. What is biologic control? Biological control is a natural method to control the size of animal, microorganism or plant populations. Biological control is based on the knowledge of inharmonious (negative) ecological interactions between species. Using such knowledge a parasite, competitor or predator species is introduced in an ecosystem in order to attain reduction of the population of another species with which it has inharmonious ecological interaction. The biological control presents the advantage of substituting the use of pesticides and other toxic chemical products in the control of plagues and diseases. It however should be employed with caution under serious previous study to avoid harmful ecological disequilibrium. A kind of biological control of some species can be done by the introduction of previously sterilized males that do not generate offspring. 149. What is bioremediation? Bioremediation is the use of microorganisms, like bacteria, protists and fungi, to degrade noxious substances turning them into non toxic or less toxic substances. Bioremediation employs microorganisms whose metabolism uses contaminants as reagents. Bioremediation is used, for example, in the decontamination of environments polluted by oil spill. In this process, bacteria that use hydrocarbons as substrate for their cellular respiration are employed. Environmental Issues: bioremediation 150. What is global warming? Global warming is the increase in the temperature of the planet due to accumulation of some gases in the atmosphere, especially gases that retain the solar energy reflected by the planet surface. The main gas that causes the global warming is carbon dioxide, CO2, but other gases act as "warming gases" too, like methane, CH4, and nitrous oxide, N2O. The exaggerated increase of carbon dioxide in the atmosphere has been caused by the burning of fossil fuels (mainly oil and coal) in industrial and urban societies and by forest fires. (It is important to note that the natural warming provided by gases of the atmosphere is fundamental for the maintenance of the planet temperature.) Predictions of studies sponsored by the United Nations stated that the global warming might cause in the near future life-threatening transformations in the planet. Countries that are the biggest emitters of carbon dioxide, like the United States and China, however, systematically ignore the warnings and continue, largely contribute to the danger. ECOLOGY Interview Questions and Answers Pdf Download Read the full article

[uncharismatic-fauna]

A Night Out with the Eastern Firefly

The eastern firefly, or North American firefly (Photinus pyralis), is a popular sight throughout the United States and southern Canada east of the Rocky Mountains. They are commonly associated with the beginning of summer, as they spend the winter hibernating underground and emerge only when the weather begins to warm. They are commonly seen in deciduous forests, grasslands, gardens, and backyards.

Contrary to their name, the eastern firefly is actually a type of beetle with well-developed wings. Adults are quite small, only 10-14 mm (0.39-0.55 in) long. They have a yellow and red head and a dark brown body with a narrow yellow stripe marking the outline of the wing casings. The main difference between the two sexes is the length of their wings; males have longer wings and are capable of flight, while females have shorter, less functional wings. Both sexes have a special organ on the end of their abdomens that produce light; however, the female's light tends to be weaker. The North American firefly produces its light by combining oxygen with a chemical called luciferin; the resulting chemical reaction gives off a glow which is amplified by special reflective cells in the firefly's abdomen.

Like all fireflies, P. pyralis uses its light producing ability to attract a mate. Males flash only while flying, in bursts about 6 seconds apart. Once a female signals her interest-- also by flashing-- the male lands near her and offers her a package called a spermatophore made of sperm, protein, and nutrients. If the female accepts, she inseminates herself and buries the rest of the package with her clutch of about 500 eggs. These eggs, which glow slightly during development, hatch about 4 weeks after being laid, and the larvae feed on the remains of the nutrient-rich spermatophore. The larvae can take one or two years to develop, and spend most of their time underground or near sources of fresh water like lakes and streams. Once the larva pupates and develops into an adult firefly, they only live in this stage for about a month before dying.

Both larva and adult eastern fireflies are predators, feeding on other insects like worms, snails, and other fireflies. However, larva spend almost all their time hunting for food, while adults spend the majority of their time seeking out a mate. To avoid predation, P. pyralis can emit foul-smelling odors and excretion of sticky substances; they also emit a chemical called lucibufagin that repells spiders. However, other species of fireflies will actually mimic the light patterns of the eastern firefly in order to predate upon them.

Conservation status: The North American firefly is currently considered Least Concern by the IUCN. However, they are threatened by light pollution, pesticides, and habitat loss.

Photos

Judy Gallagher

Katja Shultz

Sydney Penner via iNaturalist

[birdstudies]

December 5, 2023 - Long-billed Bernieria, Long-billed Greenbul, Common Tetraka, or Long-billed Tetraka (Bernieria madagascariensis) These malagasy warblers are found in evergreen and deciduous forests in Madagascar. They eat arthropods and small vertebrates, foraging in dense vegetation in flocks, often with other species. Not much is known about their breeding behavior, though one of their nests was a cup built mostly from small twigs in a shrub with a clutch of two eggs.

[willytheroadrunner-blog]

Truly a singular bird, the Great Spotted Woodpecker (Dendrocopos major) comprises all the spirits of the forest with no doubt whatsoever. Often found in old, deciduous forests of pine and oak tree, its presence will be announced almost all the time as a round of wood knocks, and some times it can't be heard unless the observer sharpens their hearing sense amidst the silence of the forest, only cut by the sound of rustling leaves. After that, it's just a game of finding where the sound comes from. If you're lucky, the bird may allow you to come close enough as to observe its drilling activity! These pecks are made by this Woodpecker as a way to reach its favourite food: xylophagous arthropods living beneath the trees' bark. Once the hole is finished, the Great Spotted Woodpecker clears it out of insects with the help of its long and muscular tongue that coils all the way to the back of its head. Moreover, this bird has a really sturdy beak, dense with structural material and reinforced by really strong head muscles which act as well as blunt force thrusters and protectors. Also, its skull has the highest bone density of all its body, making its head tough as nails and allowing the bird to use it as a literal jackhammer. These Woodpeckers make their nest inside a tree, carving a cavity big enough fot them to fit in. They defend it fiercely against predators, but they never come back to the same hole nest the next year and when spring comes they have to find a suitable spot and start all over again. Also, males and females can be told apart thanks to their feathers on the back of the neck. Red means male, as females keep a straight black colour on the same spot. Do you like what you see? Feel free to drop a comment! #woodpecker #wood #tree #green #brown #white #black #red #bird #insect #forest #bird #birds #aves #pajaros #natgeo #catalunya_animal #ocells #oiseaux #nature #wildlife #wings #flying #air #canon #nikon #birdphotography #naturephotography #animals #animal (at Llac d'Engolasters) https://www.instagram.com/p/B118dD8Ik3K/?igshid=cpp8q92xvcid

[sebastianoutside]

6/23/2017: Ovenbird - Seiurus aurocapilla

Photo by Bob Ferguson

The Ovenbird is a thrush-like member of the New World warbler Family Parulidae. It's common name is derived from the dome shaped nest which sits upon the forest floor, woven from vegetation. Each nest possess a side entrance where parents of nestlings enter to feed their young. They primarily feed on terrestrial arthropods and snails, but will add fruit to their wintering diet as well. Their scientific name stems from both Ancient Greek and Latin languages. Seiurus stems, in two parts, from "seio" meaning to shake, and "urus" meaning tail in Ancient Greek. This refers to their common behavior of bobbing their tail while walking about the forest floor. The specific epithet aurocapilla translates to "golden haired" in Latin, which refers to their distinguishing golden crown. Although it looks much like a Thrush, it is indeed a member of the New World warbler family. Genetic studies have suggested that the genus Seiurus may have diverged early on in the evolution of the family's lineage. 

It inhabits and thrives in mixed stands of primary and secondary forests of both deciduous and mixed types. They're migrants and overwinter primarily in the southeastern U.S., Caribbean Islands and Mexico to northern sections of South America. While they're a common sight in the right habitat, they're very vocal birds and especially easy to hear. Their call is characterized as a repeated CHER-tea, with each call being louder than the last. Keep an eye, and ear out for this cool little warbler. 

Until next time, there's a world we can visit. 

-S.Harris

[mealha]

Photo captures the intricacies of millipede sex

Millipedes are usually too shy to mate above ground, but this species has no issue getting it on in a petri dish. (Stephanie Ware, Field Museum/)

After much anticipation, we now know exactly how millipedes have sex. With the help of imaging techniques that take advantage of glowing millipede tissues, researchers have illuminated this arthropod’s intricate mating process. This finding marks the conclusion of a nearly 80-year quest to uncover the millipede’s genital structure.

After a pair of millipedes started getting it on, researchers from the Field Museum of Natural History in Chicago scanned both individuals and one male-female pair in an electron microscope. They also captured dozens of photos at slightly varying angles on a digital camera. By layering them digitally, they were able to clarify tiny genital details. They photographed the millipedes in both natural and ultraviolet lights, since their genitals glow under UV lighting. In a press release, the Field Museum compared the resulting photos to “a rave, albeit one made up of microscopic millipede genitalia.”

Over at UC Davis, collaborating scientists placed individual millipedes into test tubes and ran micro-CT scans, which captured and layered a series of X-ray images to visualize the bugs in 3D without the need for any dissection. The team published their findings in the journal Arthropod Structure & Development.

By examining the 3D renderings, the researchers noted that male and female millipedes likely mate in a “lock-and-key” formation. Researchers learned that the male’s gonopods—the specialized pair of legs used to insert sperm into the female—first become covered in blue-ish ejaculate. Then, he places a tiny, fleshy part of the gonopods into the female’s vulvae. At this point, the two millipedes “lock” together.

Post-coitus, the female vulvae may seal themselves closed with a gooey secretion that traps the sperm inside. When she lays her eggs, they’re coated with the stored sperm, which completes the fertilization process.

The team specifically studied the Pseudopolydesmus genus, made up of half-inch-long brown millipedes native to North America. There are more than 13,000 known millipede species total, and they each mate in unique ways. But Pseudopolydesmus caught scientists’ attention because they appear especially eager to have sex.

“One of the problems with millipedes is that they do a lot of things while they are dug into the ground, and if you take them out, you will disturb them and they’ll stop what they’re doing,” study author Petra Sierwald said in a press release. “[Pseudopolydesmus] will even mate in the lab in the Petri dish under the light.”

The millipede’s multitude of legs typically obscure the complexity of their mating process. The CT-scanning provided a clear view of the female’s vulvae glands and provided a better understanding of millipede sex mechanics.

Their discovery could eventually aid scientists in understanding the relationship between different millipede species, along with their broader evolution. Right now, for example, we don’t have the slightest idea of what most millipedes’ vulvae look like. Further research could assist in determining their current state of biodiversity, according to a complementary 2019 study.

And as Sierwald noted in the press release, the leggy, promiscuous arthropods could also “tell us about the geologic history of North America. As mountain ranges and rivers formed, groups of millipedes would get cut off from each other and develop into new species.”

Today, the leggy arthropods face challenges from climate change. As the world warms, millipedes will expand north, Sierwald says, just as they did post-Pleistocene as glaciers receded and forests spread. But a more imminent threat comes from deforestation and soil erosion, which devastates leaf litter that millipedes munch on. Conversely, disappearing millipedes could cause an excess of rotten leaves in deciduous forests. On the whole, there’s still a lot to learn about our many-legged friends—and understanding the graphic intricacies of their copulation process is a key step forward.

from Popular Photography | RSS https://ift.tt/3bJVPCJ

[kristablogs]

We finally know how millipedes have sex, thanks to glowing genitals

Millipedes are usually too shy to mate above ground, but this species has no issue getting it on in a petri dish. (Stephanie Ware, Field Museum/)

After much anticipation, we now know exactly how millipedes have sex. With the help of imaging techniques that take advantage of glowing millipede tissues, researchers have illuminated this arthropod’s intricate mating process. This finding marks the conclusion of a nearly 80-year quest to uncover the millipede’s genital structure.

After a pair of millipedes started getting it on, researchers from the Field Museum of Natural History in Chicago scanned both individuals and one male-female pair in an electron microscope. They also captured dozens of photos at slightly varying angles on a digital camera. By layering them digitally, they were able to clarify tiny genital details. They photographed the millipedes in both natural and ultraviolet lights, since their genitals glow under UV lighting. In a press release, the Field Museum compared the resulting photos to “a rave, albeit one made up of microscopic millipede genitalia.”

Over at UC Davis, collaborating scientists placed individual millipedes into test tubes and ran micro-CT scans, which captured and layered a series of X-ray images to visualize the bugs in 3D without the need for any dissection. The team published their findings in the journal Arthropod Structure & Development.

By examining the 3D renderings, the researchers noted that male and female millipedes likely mate in a “lock-and-key” formation. Researchers learned that the male’s gonopods—the specialized pair of legs used to insert sperm into the female—first become covered in blue-ish ejaculate. Then, he places a tiny, fleshy part of the gonopods into the female’s vulvae. At this point, the two millipedes “lock” together.

Post-coitus, the female vulvae may seal themselves closed with a gooey secretion that traps the sperm inside. When she lays her eggs, they’re coated with the stored sperm, which completes the fertilization process.

The team specifically studied the Pseudopolydesmus genus, made up of half-inch-long brown millipedes native to North America. There are more than 13,000 known millipede species total, and they each mate in unique ways. But Pseudopolydesmus caught scientists’ attention because they appear especially eager to have sex.

“One of the problems with millipedes is that they do a lot of things while they are dug into the ground, and if you take them out, you will disturb them and they’ll stop what they’re doing,” study author Petra Sierwald said in a press release. “[Pseudopolydesmus] will even mate in the lab in the Petri dish under the light.”

The millipede’s multitude of legs typically obscure the complexity of their mating process. The CT-scanning provided a clear view of the female’s vulvae glands and provided a better understanding of millipede sex mechanics.

Their discovery could eventually aid scientists in understanding the relationship between different millipede species, along with their broader evolution. Right now, for example, we don’t have the slightest idea of what most millipedes’ vulvae look like. Further research could assist in determining their current state of biodiversity, according to a complementary 2019 study.

And as Sierwald noted in the press release, the leggy, promiscuous arthropods could also “tell us about the geologic history of North America. As mountain ranges and rivers formed, groups of millipedes would get cut off from each other and develop into new species.”

Today, the leggy arthropods face challenges from climate change. As the world warms, millipedes will expand north, Sierwald says, just as they did post-Pleistocene as glaciers receded and forests spread. But a more imminent threat comes from deforestation and soil erosion, which devastates leaf litter that millipedes munch on. Conversely, disappearing millipedes could cause an excess of rotten leaves in deciduous forests. On the whole, there’s still a lot to learn about our many-legged friends—and understanding the graphic intricacies of their copulation process is a key step forward.