Re: [dinosaur] Feathered dinosaurs (free pdf)

[Tim Williams <tijawi@gmail.com>]

This is a pretty excellent review overall. However, if I was _Microraptor_ I'd be forgiven for feeling a little miffed. Twice it's claimed that _Microraptor_ was most probably only a glider, unlikely capable of powered/flapping flight. This is despite the fact that its flight adaptations are on par with those of _Archaeopteryx_, for which the notion of powered flight is uncontroversial. In some respects _Microraptor_'s flight adaptations are actually superior to those of _Archaeopteryx_: _Microraptor_ has an ossified sternum and an alula, two features missing from _Archaeopteryx_. There have been abundant studies which have determined that _Microraptor_ was eminently capable of flapping flight (and was even capable of take-off) - including papers in the recent Bulletin of the AMNH monograph of Pennaraptora. I'm mystified why some people are determined to dismiss poor _Microraptor_ as just a passive glider, undeserving of powered flight.

On Tue, Nov 17, 2020 at 3:48 PM Ben Creisler <bcreisler@gmail.com> wrote:

Ben Creisler

bcreisler@gmail.com

A new paper with free pdf:

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Daniel T. Ksepka (2020)
Feathered dinosaurs.
Current Biology 30(22): R1347-R1353
doi: https://doi.org/10.1016/j.cub.2020.10.007

https://www.cell.com/current-biology/fulltext/S0960-9822(20)31511-6

https://www.sciencedirect.com/science/article/abs/pii/S0960982220315116Â

Free pdf:
https://www.cell.com/action/showPdf?pii=S0960-9822%2820%2931511-6


Feathers are the most complex integumentary structures in the animal world. They come in a variety of forms, the most familiar of which are remiges (flight feathers). Flight feathers are composed of a central shaft made up of a hollow calamus (quill), which is inserted into the skin, and a more distal rachis. Hundreds of parallel barbs branch from the sides of the rachis. In turn, smaller hooked barbules branch off the barbs, allowing them to interlock in a tight zipper-like fashion to form vanes. Variations in rachis, barb and barbule morphology result in other feather types such as contour feathers, bristles and down feathers. Feathers have a remarkable array of functions -- they form airfoils and elaborate display structures, they serve to camouflage and insulate, to generate and help detect sound, and even to disintegrate into powder to condition other feathers.

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