todropscience - Tumblr blog

[todropscience]

Freeze! You’re under arrest for being so nice and cute. Copy this message to 10 other blogs that you think are beautiful and deserve it. Keep the game going and make others feel beautiful!!!

[todropscience]

Hello, I have read that the Mantas put 20 eggs but inside this 20 eggs (mermaid pocket) they have 400 more eggs, i don't understand that. Also, i have read that this eggs normally are attach to algas to feed when they are born, but then again i have seen videos of the mantas being born of the inside of the mom. it is because they are different species? please i would love to know that. thank you so much.

When you say mantas, you are talking about manta ray aka devils ray, which are pelagic and travelers batoids, very famous, and seen in snorkel and diving spot in tropical parts of the world. These species do not lay eggs, but rather become pregnant and give birth.

Distant relatives to manta rays are skate (ajidae) and in some cases they lay eggs.

There are big species, who lay big egg cases. such is the big skate (Beringraja binoculata), and particulary, this one is know to lay around (in some cases) 5 to 10 eggs or embryos, inside one single egg case or mermaid pocket.These eggs are fertiliced insided the female, after the copula. Then, the eggs are closed insided the egg case and laying on the seafloor.

howard, 2017

but in other cases, small skate species, usually coastal, lay a lot of egg cases with a single egg inside, each egg case have tendrils who entangles, and these female lay a lot of egg (or it is likely a group of female laying egg in groups) here is one example of numerous egg cases lay together.

[todropscience]

I came to my lunch table today and found myself in a strange debate with some friends that I think is a bit stupid.

My friend argues that whales can apparently get anorexia, but according to the Google dictionary definition of anorexia, anorexia is a disorder where you stop eating enough because of worrying about gaining weight, which I'm pretty sure whales don't have to worry about.

I'm not knowledgeable in marine biology so for all I know whales could have societal standards, but I was hoping you could clear this up and end this odd debate?

No such thing as a stupid question!

I believe they who argue whales can get anorexia should support their hypothesis with strong evidence. As far I know, and after a rapid online research I have not found a thing about this. What we know is in some cases when whales eat plastics and such waste prevented it from eating food, which make them starve.

[todropscience]

This is the first report of sex in humpback whale, and is the first report of sexual activity between two male

Yes, the first report of sex in humpback whales is homosexual activity. Despite decades of research on humpback whales around the world, reports of penis extrusion by males are relatively rare and copulation in humpback whales has not yet been documented. 

The unprecedented event was recorded opportunistically on January 19, 2022, near the Molokini crater off the island of Maui, Hawaiʻi. Two humpback whales were seen engaged in copulation for the first time in recorded history, but after photo analyses along molecular studies, revealed both were mature males.

According to researchers, cetaceans such as humpback whales could use the genital slit or anus for same-sex copulation, to practice reproductive behaviors or nonreproductive sexual behavior such is forming social alliance or assert a sort of dominance.

Reference (Open Access): Stack et al., 2024. An observation of sexual behavior between two male humpback whales. Marine Mammal Science

[todropscience]

NEMO FISHES CAN COUNT STRIPES, SCIENTISTS SAY

Clownfish, aka anemonefish, famous by their distinct white bar patterns seen in Disney’s Finding Nemo, can count up to three, a new study finds.

There around 28 different species of anemonefish know to date, having between 0 to 3 white stripes, which has been suggested to be important for species recognition. In a recent study, researchers found out that in lab conditions, common anemonefish (Amphiprion ocellaris), a species that displays three white bars, when faced with an intruder fish, attacked their own species more frequently than other species of intruding anemonefish.

Recearchers tested how common anemonefish could count number of stripes, and they used orange plastic models with different numbers of bars, and compared whether the frequency of aggressive behavior towards the model differed according to the number of bars. The frequency of aggressive behavior toward the 3-bar model was the same as against living common anemonefishes and was higher than towards any of the other models.

-Plastic models used to measure the aggressive behavior of clown fish. Clownfish could count stripe and shown aggresive behavior following the number of stripe. Photo by Kina Hayashi.

Researchers believe common clowfish count the number of white stripes as a cue to identify and attack only competitors that might use the same anemone where they live, using counting as an important behavior for efficient host defense.

Photo: Gaell Mainguy ·

Reference (Open Access): Hayashi et al., 2024. Counting Nemo: anemonefish Amphiprion ocellaris identify species by number of white bars. Journal of Experimental Biology

[todropscience]

Altruism is the behavioral assistance of another in need, has ancient origins in mammalian evolution. Recently, marine ecologists has observed for the first time, an act of altruism performed by a male northern elephant seal (Mirounga angustirostris), when trying to protect a young pup in distress from drowing at high tide at a colony at Point Reyes National Seashore, California.

Researchers noted the high tide had pulled the pup into the water and it was yelling for help. The male reacted and entered to the water, it swam to the pup and very gently nudged it to shore, near to where its mother was waiting. Marine ecologists did not report the male attempted to gain an approach or interest in the mother of the pup. Male altruism is rarely seen in marine mammals, as sea lions and elephant seals, and more examples may emerge as more efforts were focused on breeding colony observations.

Photographs: Above: Male helping the pup from drowing. Below: mother and her pup reunited after the event.

Reference (Open Access): Allen et al., 2024. An observation of potential altruism by a male northern elephant seal (Mirounga angustirostris). Marine Mammal Science.

[todropscience]

The white shark (Carcharodon carcharias) is the largest predator fish in the world, however, the early life history and reproduction of this iconic shark is still poorly understood, in fact, no one has seen a white shark puppy in the wild, nonetheless, recent aerial observations made by drone off California, USA, have revealed the first images of a white shark puppy.

Footage done by wildlife filmmaker Carlos Gauna and biologist Phillip Sternes in July 2023, revealed seconds of a single pale pup, which apparently was shedding its embryonic layer. This record robusts the idea the coast of central California acts a birthing location for white sharks. This shark was stimated to reach 1.5 m in lenght. Many researchers believe white sharks are born farther out at sea, due the elusivity to find pups. This finding means they are likely to born in shallow waters.

Photo: Carlos Gauna

Reference : Gauna & Sternes2024. Novel aerial observations of a possible newborn white shark (Carcharodon carcharias) in Southern California, Environmental Biology of Fishes

[todropscience]

SOUTHERN RIGHT WHALE CALVES ARE LITTLE MILK THIEVES

Drone footages made during the nursing season, off Encounter Bay, South Australia have revealed an unknown behaviour in southern right whales (Eubalaena australis), with some calves involved in direct and intentional movement to steal milk from other lactating mothers, with the intention to drink some delicious extra milk.

This phenomenon called allosuckling has potential benefits for the calf as it may gain extra milk to help it grow in size and strength, but it may be disadvantageous to the non-biological mother as she needs to provide milk to her own offspring. According to lead researcher of the study, whales have a capital breeding strategy, where during the nursing season the mother does not feed and is not able to replenish her lost energy reserves.

Allosuckling, the suckling of milk from a non-biological mother, occurs in some species of mammals, whoever, this is the first time is reported in baleen whale calves.

Gif description: A calf performing allosuckling, and the non-biological mother showing an evasive reaction, Sprogis & Christiansen, 2024.

reference (Open Access): Sprogis & Christiansen, 2024. Allosuckling in southern right whale calves. Mamm Biol

[todropscience]

RESEARCHERS NAMED A NEW SPECIES AS THE SANDWICH-TAIL

Dwarf stingrays (Brevitrygon spp), are found in soft bottoms in the continental shelves of the Indo-West Pacific from the Red Sea to Indonesia. These are usually found in fish markets along their distribution, and are frequently misidentified. Now, stingray experts have uncovered a new Brevitrygon species, from specimens collected between 1955 and 2014 from Pakistan to Mumbai, western India.

The sandwich-tail whipray (Brevitrygon manjajiae) is named after Dr. Mabel Manjaji-Matsumoto, the first researcher to identify and name the rays in the 60' as sandwich-tail, following the color of the tail, as it have dark brown on the top and bottom sides of its tail with white sides.

-Lateral and dorsal view of the post-sting tail of Brevitrygon manjajiae, showing the "sandwhich-like coloration.

Now, researchers have cleared the natural history of these dwarf stingrays, and have realized the species varies depending on where they are found, as these stingrays usually do not overlap in their distribution, making easy their identification.

Photo: A male sandwich-tail whipray collected from the Arabian Sea near Pakistan. Scale bar: 2 cm

Reference (Open Access): Last et al., 2023. The Indo-Pacific Stingray Genus Brevitrygon (Myliobatiformes: Dasyatidae): Clarification of Historical Names and Description of a New Species, B. manjajiae sp. nov., from the Western Indian Ocean. Diversity

[todropscience]

DEEP-SEA MINING MIGHT HARM RARE JELLYFISH

New research shows mining of the deep ocean floor for rare minerals could harm deep-sea jellyfish by stressing them out with sediment plumes, suggests a study of how resource harvesting might affect the helmet jellyfish (Periphylla periphylla), a luminescent red-colored cnidarian of the deep sea.

While deep sea animals provide important ecosystem functions including climate regulation, species-specific responses to stressors remain poorly understood. Researchers collected helmet jellyfish and exposed them to sediment at concentrations that could be churned up by mining. After a day, the animals had mucus covering much of their bodies, among other signs that they were really not well, being stressed and using a lot of energy to rid out of the floating sediment, which could be harmful over extended periods.

Suspended sediment plumes provoked the most acute and energetically costly response through the production of excess mucus. Microbial symbionts appeared to be unaffected by both stressors, with mucus production maintaining microbial community composition. If these responses are representative for other gelatinous fauna, an abundant component of pelagic ecosystems, the effects of planned exploitation of seafloor resources may impair deep pelagic biodiversity and ecosystem functioning.

Photo by Bjørnar Solhaug

Reference (Open Access): Stenvers et al., 2023. Experimental mining plumes and ocean warming trigger stress in a deep pelagic jellyfish. Nature Communications

[todropscience]

The Javan Stingaree (Urolophus javanicus) has become the first species of marine fish declared extinct in modern times. The IUCN has declared the Javan Stingaree extincted after an assessment led by an international team of scientists.

Stingaree are round rays native to the western Pacific Ocean and the Indian Ocean, with 21 species know to science. The Java Stingaree was known only from a single specimen collected in 1862 from a fish market in Jakarta, Indonesia. In the present, the habitat where this species was known to occur, is heavily industrialised, with extensive, long-term habitat loss and degradation. Researchers carried out new ecological models to understand current distribution and tendency to find out the specie is virtually extinct, likely by the intensive and unregulated fishing, and habitat loss.

Photo credit: Edda Aßel, Museum für Naturkunde Berlin.

More at IUCN

[todropscience]

ANTARTIC PENGUINS CHAMPIONS OF POWER NAPS

Microsleep in humans are dangerous when driving, but just now, researchers found out penguins dominated microsleep, using these short sleep periods as strategy to balance sleep and vigilance requirements. An international team of researchers at the King George Island were looking at breeding chinstrap penguins (Pygoscelis antarcticus) using remote electroencephalogram monitoring, to they found out penguins nodded off more than 10,000 times a day, for only around 4 seconds at a time, but penguins still managed to accumulate close to 11 hours of sleep.

The brown skua (Stercorarius antarcticus), are very smart birds, and one of the main predators in nesting colonies. During incubation, skuas are known to prey on penguin eggs mainly on the border of the colony. As one penguin parent must therefore guard the eggs or small chicks continuously while its partner is away on foraging trips lasting several days, they face the challenge of needing to sleep while protecting their offspring In addition, they also have to effectively defend their nest site from intruding penguins, they need to stay alert.

-Recordings showing typical microsleep episodes in chinstrap penguins.

The investment in microsleeps by successfully breeding penguins suggests that the benefits of sleep can accrue incrementally.

Reference (Open Access): Libourel et al. 2023. Nesting chinstrap penguins accrue large quantities of sleep through seconds-long microsleeps. Science

[todropscience]

AFRICAN PENGUINS IDENTIFY PATNERS BY THEIR CHEST DOTS

Birds are known to be highly social and visual animals, and penguins are not the exception, as they live in dense colonies. Yet no specific visual feature has been identified to be responsible for individual recognition in birds. Now, researchers demonstrate that african penguins (Spheniscus demersus) can recognize their each others using their ventral dot patterns.

Researchers placed a experiment at the Zoomarine Marine Park, in Rome, Italy, to test how penguins will react to a model with plain with no dot penguin, and to penguins with dots, to find out penguins actually could visually recognize the dots of their lovers and friends in the zoo.

Penguins rely strongly on their ventral dot patterns for individual recognition, and may have holistic representations of other penguins in the colony. In this video below, an african penguin named Gerry appears to recognize his mate, Fiorella (left), in an individual recognition experiment.

These findings suggest that african penguins may rely on a more holistic visual representation of their partner, which includes both the ventral dot patterns and their partner's facial features. Notably, these abilities are not dependent on the ability of a pair to produce offspring together. Nemo and Chicco, male partners, showed the same preference for each other as other penguin partner pairs, suggesting that the ability to distinguish the partner from others is driven simply by the special bond developed between nesting partners.

Photo: Few members of the Zoomarine Italia penguin colony. Unique ventral dot patterns are visible on each penguin's chest. Photo: Cristina Pilenga.

Baciadonna et al., 2024. African penguins utilize their ventral dot patterns for individual recognition. Animal Behaviour.

[todropscience]

The Japanese green syllid Megasyllis nipponica, is a bristle worm native from the coast of Japan, but now is know to live in coastal parts of California where is stablished. This little dance seen in the GIF have a reproductive reason, and researchers now explaing better what is happening, and you may not be prepared to this.

The brown and dancing body segment is called the stolon, which detaches from the worm in a unique reproductive process called stolonisation or schizogamy. When gonads are matured, the stolon developed a head, which even posses eyes, antennae and bristles, then the stolon can break off and swim away, to break apart to release eggs or sperm. This bizarre process continues before the stolon detaches when it develops nerves and a ‘brain’, allowing it to swim independently from the original body.

Video and figure by Nakamura et al 2023

Reference (Open Access): Nakamura et al. 2023 Morphological, histological and gene-expression analyses on stolonization in the Japanese Green Syllid, Megasyllis nipponica (Annelida, Syllidae). Sci Rep

[todropscience]

FIRST SIGHTS OF THE RECENTLY DISCOVERED DEEP REEFS FOUND IN THE GALAPAGOS

Scientists from the Fundación Charles Darwin and the Schmidt Ocean Institute found ROVs have discovered two pristine cold-water coral reefs in the vicinity of the Galápagos Islands. These new to science ecosystems are situated at depths ranging from 370 to 420 meters. The discovery expands our understanding of deep reefs within the Galápagos Islands Marine Reserve.

The larger of the two reefs has over 800 meters in length, while the second measures 250 meters in length. They exhibit a rich diversity of stony coral species, suggesting that they have likely been forming and supporting marine biodiversity for thousands of years. This discovery follows the April 2023 finding of the first deep coral reefs in the Galápagos Marine Reserve by Woods Hole Oceanographic Institution scientists.

Video and photos available here.

More at Schmidt Ocean Institute

[todropscience]

PLASTIC POLLUTION PREVENTION INSTEAD PLASTIC REMOVAL, RESEARCHERS SAY

A new international research highlights that plastic removal technologies have shown varied efficiency in the amount of waste material they are able to collect, in fact, plastic removal technologies used so far have have not been tested at all. Some have been shown to harm quantities of marine organisms, including fish, crustaceans and seaweeds, that far exceed the amount of plastic captured, meaning their overall impact on the ocean is potentially more harmful than helpful.

Plastics accumulates in all environments, from the highest mountains to the deepest oceans, whoever, plastic production is projected to triple by 2060, with plastic pollution increasing correspondingly under business-as-usual scenarios.

According to researchers, plastic removal technologies can temporarily mitigate plastic accumulation at local scales, but evidence-based criteria are needed in policies to ensure that they are feasible and that ecological benefits outweigh the costs. To reduce plastic pollution efficiently and economically, policy should prioritize regulating and reducing upstream production rather than downstream pollution cleanup.

There are innovations for the open ocean and the seabed that use combinations of towed nets, autonomous vessels and artificial intelligence, but researchers say that even if these technologies were to show signs of being truly effective, they would barely scratch the surface of the global problem. Cleanup practices could also lead to greenwashing through new schemes to offset the use of plastics through plastic collection.

Marine turtle trapped in a plastic fishing net, by Jordi Chias sourced from National Geographic.

Reference (Open Access): Bergmann et al. 2023. Moving from symptom management to upstream plastics prevention: The fallacy of plastic cleanup technology, One Earth.

[todropscience]

LONGEST MIGRATION OF A SOUTHERN RIGHT WHALES RECORDED

Why the the southern right whale cross the Atlantic ocean? because the krill.

Southern right whales (Eubalaena australis) typically migrate between summer, high-latitude offshore foraging grounds and winter calving grounds located in coastal, temperate waters. But now, the satellite tracker for a southern right whale from South Africa, named 221423, which had been silent for months, misteriously appeared in south Argentina. The satellite tracker revealed the first scientifically documented case of a southern right whale crossing the Atlantic.

Whale 221423, swam to coastal Argentina, traveling a total of 15,288 kilometers. This distance far exceeded the findings of a previous tagging study that found the longest distance to be around 7,000 kilometers. Another whale traveled an unexpected 9,000 kilometers to the South Sandwich Islands, a feeding area typically frequented by western right whales. 

Premodern and modern whaling operations nearly extirpated the southern right whale, declining in nearly 100,000 individuals in the early 1800s to a few hundred individuals around the 1920s. However, thanks to current protection of the species, they have been recovering steadily in parts of their historical range, particularly in the coastal wintering and calving areas of Argentina, Brazil, South Africa, Australia, and New Zealand.

Photo above: Left showing 221423 taken in Walker Bay, South Africa, on October 13, 2021, immediately after tagged. Right: Photograph of 221423 taken in the Falkland Islands (Islas Malvinas) on July 9, 2022.

Map indicating the movement patterns of four adult female tagged on the South African coast in October 2021.

Reference (Open Access): Vermeulen et al., 2023. Swimming across the pond: First documented transatlantic crossing of a southern right whale. Marine Mammal Science.