Of dinosaurs and feathers

A 2014 study in Science – provocatively titled “A Jurassic ornithischian dinosaur from Siberia with both feathers and scales” – might just change how we think about all dinosaurs. Based on the age and identity of the specimen that the paper describes, the authors say perhaps all dinosaurs, not just the ones closely related to modern birds, had feathers! How cool is that?

“Probably that means the common ancestor of all dinosaurs had feathers,” says study lead author Pascal Godefroit of the Royal Belgian Institute of Natural Science in Brussels. “Feathers are not a characteristic [just] of birds but of all dinosaurs.”

National Geographic covered the story (about the little guy illustrated below) here.

This illustration of Kulindadromeus zabaikalicus, a newfound feathered dinosaur, shows it in its natural environment. Illustration by Andrey Atuchin; reposted from nationalgeographic.com

The secret ingedient is…crystals?

Chameleons are pretty special. With their independently moving Mad-Eye Moody eyeballs

and their “live long and prosper” hands,

Is Spock really a well disguised chameleon? That is not a very logical conclusion (despite their similar hand morphologies).

Probably has a killer Vulcan Death grip.

who isn’t intrigued by these goofy lizards?

Perhaps their most amazing feature is their ability to change color.

Recent research shows that the key to this process may be less biological and more CRYSTALS.

Studying male panther chameleons from Madagascar, a cross-disciplinary team of biologists and physicists from the University of Geneva found that the reptiles’ skin is covered by a thick layer of light-reflecting cells called iridophores, which are embedded with photonic crystals—a latticed organization of guanine nanocrystals. Depending on how closely those crystals are clustered, they reflect different wavelengths of light.

Read more in “The Secret to How Chameleons Change Color” over at wired.com or go straight to the (open!) source at Nature Communications – “Photonic crystals cause active colour change in chameleons“.

So – you want to be an academic?

Stumbled upon a great little slide show (by Josh Neufeld) with all the major pros (and some cons) of being an academic – from start to finish. There’s no script to go with the slides, but they’re put together in such a way that I think it’s pretty coherent as is. It also contains a lot of google-able resources for those knee deep in academia too. (Hat tip to @hollybik!)

National Darwin Day? (Yes, please.)

Charles Darwin is great, isn’t he? I mean – he discovered the theory of natural selection and by doing so, created an eloquently beautiful framework for studying and understanding the living world around us. He wrote On the Origin of Species (free text here!). He drew this:

“I think case must be that one generation should have as many living as now. To do this and to have as many species in same genus (as is) requires extinction . Thus between A + B the immense gap of relation. C + B the finest gradation. B+D rather greater distinction. Thus genera would be formed. Bearing relation” (next page begins) “to ancient types with several extinct forms”

Every year on February 12 (Darwin’s birthday), evolution enthusiasts celebrate Darwin Day with nerdy games, scientific seminars and frivolity. Mark your calendars! And this year, it may be even better, since bills (yes, plural!) have been introduced to the House of Representatives and to the Senate to officially name February 12, 2015 Darwin Day. Follow the links to read more. And from what I know about scientists, if we were to ever achieve a federal holiday for Darwin, I think we’d party harder than New Years, explode more things than Independence Day and drink more coffee than finals week. Dar-win! Dar-win! Dar-win!

An artichoke with legs: the pangolin

c026c5902911ebd8cf6c7c912cca0631Some days I just need a pick me up. While others take to the internet and fine photos of kittens telling them to hang in there, I seek the adorable face of the pangolin._80790888_cape_pangolin_spl624

Also known as the spiny anteater, it is the only mammal wholly covered in scales. They resemble artichokes on legs. Oh and they are beyond adorable.  415e1bec42a96a15e13e0323be919600

However, all 8 species of pangolins are endangered because they have one more distinction: the worlds most trafficked mammal. Their meat has become a delicacy in vietnam, which has rapidly wiped out populations of pangolins across South East Asia.

Read about their plight over at BBC, and for a little Friday pick me up, enjoy these lovely photos of my favorite mammal.

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Did Marine Mammals Merge Molecularly? Maybe.

Morphological convergence is one of the most striking patterns in evolution. Just among mammals there are spectacular and bizarre examples of distantly related species that share surprisingly similar adaptations. I bet you’ve heard of saber-toothed cats. But what about marsupial saber-toothed cats? Raccoons are surely familiar, but have you heard of raccoon dogs? Or the earless, eyeless oddity that is the golden mole, which somehow looks almost exactly like the equally earless and eyeless notoryctid marsupial mole? My favorite, though, might be the lesser hedgehog tenrec from Madagascar, which bears the same tiny coat of spiked armor as the common hedgehog but is more closely related to an elephant.

Skull from the marsupial saber-toothed “cat” Thylacosmilus.

Skull from a placental saber-toothed cat Smilodon.

Until recently, most scientists studying evolutionary convergence have focused on the converged phenotype (external appearance), but with the arrival of ever-cheaper DNA sequencing technologies, scientists can efficiently study patterns of convergent genotypes across thousands of genes in species that appear to have converged at the phenotypic level.

Now, I know dancing sharks are the preferred marine species of the moment, but allow me to reignite your interest in some other denizens of the sea. Last month, a team of researchers published a study in Nature examining how genes in three marine mammal lineages might have converged independently on the same solution to the very hard physiological problem of living in the ocean after millions of years evolving on land (Foote et al. 2015). Their results are hardly conclusive but do illustrate a compelling new way to think about and study convergence now that genomes are getting so cheap to produce.

Katy Perry and her dancing sharks at the 2015 Super Bowl

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