#like proto feathers but with butterfly scales ^^

[sunni-d-meadows]

I’m v curious, in the comic Viktor’s wing stubs are on his shoulder blades, but in the new full design they look to come from the lower back. Does that mean these are separate wings? Does Vik gain new ones at any point?

Honestly i'm so glad you noticed because I realized what I had done LOL So originally I was going to show how the "scales" of his wings actually go all the way down his back kind of like how some "bird people" have wings on their lower back instead of their upper back. But when his wings actually come in, they develop on his lower back while the scales end up being more... like feathers? its hard to explain so here's a visual! :3 <3 I hope this answers your question! As far as more wings? Now that's an interesting thought... He's definitely not used to them either.

[o-craven-canto]

What is your position on the debate between contingency and convergence in evolution? As a creator and enjoyer of speculative evolution, I imagine you might fall more towards contingency, but I'd still be curious on your overall thoughts on it, and on how different a separate run of evolution on an earthlike planet would really be.

Hmm.

Biologists usually distinguish two types of resemblance among organisms: analogy, which mostly regards general function and appearance and is driven by common conditions, and homology, which mostly regards deep structure and is driven by common ancestry.

All the limbs of land-dwelling vertebrates and their descendants are made of one long bone, followed by two parallel long bones, followed by a maximum of five (except in ichthyosaur flippers) series of digit bones. This you see from frogs to seagulls to horses to manatees to moles -- the descendants of proto-amphibians such as Ichthyostega -- but not in any other animal group. This is the canonical example of homology: there is no reason for such different limbs with functions so different to share the same 1-2-n pattern except inheritance from a common ancestor. On the other hand, the wings of birds and those of insects, or for that matter their eyes, are so different because they arose independently. The common features in the wings of a hummingbird and a dragonfly are due to the same physical constraints, and that is analogy.

Sometimes it depends from the level of analysis: bird wings and bat wings are analogous as wings -- their flight surface is achieved by different means, feathers in one and skin in the other -- but homologous as vertebrate forelimbs -- they have the same 1-2-n sequence of bones, and their development is regulated by the same genes.

There are, of course, physical reasons for structures to resemble each other: everything that moves quickly through water needs to be more or less spindle-shaped; everything that grows past a few hundred grams on dry land needs some sort of rigid support; photosynthesizers and filter-feeders need fractally branching structures; and so on. Compound eyes and exoskeletons really are more efficient at smaller sizes, camera-type eyes and internal skeletons at larger, so that's a reason other than ancestry for insects and birds to be so different; but the largest butterflies are bigger than the smallest hummingbirds, so it's not just a matter of scale; and the eyes of tunas are more like the eyes of eagles than like the eyes of squids, so it's not just a matter of environment.

Some classical examples of convergent evolutions overstate their case a bit: sharks, ichthyosaurs, and dolphin all started from the same aquatic vertebrate chassis, so their similarity is not pure environment-driven convergence. (But it is a bit: from the same chassis you can also make a turtle or a crane.) Similarly for marsupial mice and moles vs. their placentate equivalent, none of whom gets that far from the original mammal model to begin with. When you get a bit farther, you find that the Australian equivalent of a horse is not an almost identical "marsupial horse" but a kangaroo, for reasons that have to do with marsupial birth. It's the same for the now-famous case of carcinization, which only applies to decapod crustaceans -- it's not even universal for crustaceans in general! If you try over and over to make an open-water pursue predator out of the vertebrate plan, you'll get similar results: the shark, the tuna, the ichthyosaur, the dolphin. But try the same with the mollusk plan, and you get a squid.

Now, convergence is likely to occur on other planets, because anything recognizable as life will have similar requirements and meet similar challenges. But it will be much more subtle than making planets full of blue horses and humans with weird eyebrows (I can't overstate how complex and specific the history of our body shape is). Assuming an Earth-like planet, for example, I'd expect its surface ecosystems to be overwhelmingly based on photosynthesis, its "plants" to have branching shapes with flat light collectors, and its largest "animals" to be bilaterally symmetrical with eyes, intestines, and skeletons of some sort. But that still leaves an enormous amount of variety, based both on ancestry and on smaller-scale micro-environmental constraints: note that the description of "animal" I gave fits equally a tarantula, a giraffe, a snail, and an axolotl.

TL;DR: many important traits of living organisms are made necessary by physical and environmental constraints, but there's an immense variety of ways to develop them, and that is mostly going to be driven by contingencies in ancestry. In my opinion, that is.

As readings, I'd recommend The Equations of Life: How Physics Shapes Evolution (Charles Cockell, 2018) and Convergent Evolution on Earth: Lessons for the Search for Extraterrestrial Life (George McGhee, 2019) as summaries of the physical constraints and useful strategies that are going to arise over and over in living systems, as well as this brief paper on the evolution of complexity in alien life. Note how much similarity they predict, but also note how much they don't!

Thanks for the question! <3

[ntrending]

Now paleontologists know what colors graced these 200-million-year-old butterfly wings

New Post has been published on https://nexcraft.co/now-paleontologists-know-what-colors-graced-these-200-million-year-old-butterfly-wings/

Now paleontologists know what colors graced these 200-million-year-old butterfly wings

The blue morpho butterfly is arguably the most glamorous insect on the planet, and you’d know instantly if you saw one. Spanning wider than your hand, its wings flash an iridescent blue sheen so bright it seems to glow.

And in some sense, the blue morpho does glow: not by emitting light, but by refracting it, thanks to an optical trick that evolved in butterflies, along with some other insects, plants, birds, and mollusks. And according to new research from the Chinese Academy of Sciences, butterflies started displaying these flashy colors a long, long time ago.

The blue morpho belongs to a group called lepidoptera that includes butterflies and moths, notable among insects for their widely varied and highly inventive wing patterns. Their stylings range from dull colors to patterns mimicking eyes, drops of water, leaves, wasps, other poisonous butterflies, and even those painted with shades of cellophane and oil slick. And scientists want to know how far back in time those hues stretch. “Colors are the basis for diverse communication strategies,” says Bo Wang, an author on the new study, out today in Science Advances. “If we know the colors of ancient insects or other animals, we can get more information about their ecology.”

Back to the morpho’s brilliant blue. It is due to something called “structural color.” Instead of a pigment that chemically scatters specific wavelengths of light, structural colors are physical, crystalline arrangements that refract light, as though through a prism. With features smaller than a quarter of a wavelength of light, these structures are invisible to the naked eye, made of stacks of highly refractive, colorless material like collagen or keratin or even layers of pigment like melanin. In lepidoptera, the tough, chitinous scales of the wings themselves exhibit intricate ridges and layers that can conjure vivid, metallic hues from light. But the same principle is at work in the feathers of a peacock’s tail, the scrotum of a vervet monkey, and the shiny green shell of an invasive Japanese beetle.

Nipam Patel, a researcher at UC Berkeley who studies how structural color develops on modern butterfly wings, has catalogued the sheer variation of these structures: “They can be as simple as a flat layer of the right thickness or a very complicated, Christmas-tree shape,” like the cross section of a blue morpho wing scale. “Sometimes you get what seem like really complicated solutions that arose independently,” he explained, with the same nanostructure exhibited by distantly related groups, evidence that structural color is a useful tool that lepidoptera have evolved again and again over millions of years.

In the new study, researchers examined more than 500 butterfly specimens, ultimately selecting six that were well preserved enough to reveal their secrets. The specimens date to the Jurassic period, as much as 200 million years ago. Fossilized in stone—and in the case of one proto-butterfly, preserved in amber à la Jurassic Park—the colors of the wings are gone, but their nanostructure is preserved. The scientists examined these scaffolds under an electron microscope to reveal their pattern; a lower level of small, tightly packed scales and an upper layer with larger segments ridged in a herringbone pattern. Modeling these arrangements in a computer, the researchers were able to determine how they would have scattered light, which in turn revealed what color they would have been.

In all of the six specimens, the wings exhibited a broad-band scattering which would have appeared as a light tawny brown with a metallic, soap-bubble sheen. To the researchers, their finding indicates a pattern of wing scales that has been an integral part of the lepidoptera family from its earliest forms. Only later, during the Cretaceous period, did this single structural formation explode into the full range of optical illusions butterflies and moths would eventually develop.

Though all of the Jurassic specimens belong to families and species long extinct, their closest living relative is a kind of primitive moth today called micropterigidae. They are small and furred, with wings a brassy greenish-gold that could also be described as kind of brown. The blue morpho they are not. But from this humble beginning, the trippy patterns and intense colors of today have sprung.

Written By Amelia Urry