In my previous posts I did talked about the origin of the filamentous structures in Ornithodira, the ones I nicknamed stem-feathers since I did believe they could be homologous but was not sure if those structures could be called feathers. And a couple days ago we got the answer for this question in the form of a new paper by Yang et al.(in press.) presenting us to two little feathered pterosaurs.
Using varied methods the authors analyzed the raw morphology, ultrastructure and the chemical composition of the filaments; leading them to the conclusion that this similarity probably confirms the homology of those structures. The do talk a bit about the original function of those structures being insulation (the one I did support in previous posts), use as sensory organs, enhance camouflage and making the animals more streamlined.
This paper support the ideas I did present in previous posts, the small bodied basal homeothermic Ornithodirans would probably need some form of insulation so they would not suffer the risk dying of hypothermia; we knew about the homeothermic characteristic and now we know they were feathered what we only need is a study modeling the climate of Southern Gondwana to see if it was necessary for their survival.
This will also open space for new discussions about when and why many dinosaur groups like sauropods, thyreophorans, hadrosauriforms and large theropods lost most if not all this form f integument. For the subject of paleoart it does open many possibilities of depictions of feathery structures in non-conventional groups like some fuzzy tufts on the head of sauropods.
Now knowing that feathers are ancestral to at least Ornithodira, and those are not only simple filaments but very complex branched structures, it opens the space for the question: "Are feathers an even more basal trait?"
We know for some time that crocodilian osteoderms B-keratin is similar to the one of ornithodiran filaments, also since modern pseudosuchians common characteristics with other "reptiles" like petiolethermy are a secondary acquisition could the "scaly/osteodermic" also is a secondary character and basal members might have been feathery/fuzzy as well?
As many times in science answering a question brings up many more, and this will be the scenery after Yang et al, (in press.), we answer the question is feathers are an ancestral trait for dinosaurs only to open space for the question if it is an ancestral trait of Archosauria. 2018 was not the most vibrant year of paleontology but ending the year with this new amazing paper is very nice and may be a good sign for 2K19.
References:
YANG, Zixiao et al. Pterosaur integumentary structures with complex feather-like branching. Nature Ecology & Evolution, v. 3, n. 1, p. 24, 2019.
DALLA VALLE, Luisa et al. β‐keratins of the crocodilian epidermis: composition, structure, and phylogenetic relationships. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, v. 312, n. 1, p. 42-57, 2009.
This will also open space for new discussions about when and why many dinosaur groups like sauropods, thyreophorans, hadrosauriforms and large theropods lost most if not all this form f integument. For the subject of paleoart it does open many possibilities of depictions of feathery structures in non-conventional groups like some fuzzy tufts on the head of sauropods.
Now knowing that feathers are ancestral to at least Ornithodira, and those are not only simple filaments but very complex branched structures, it opens the space for the question: "Are feathers an even more basal trait?"
We know for some time that crocodilian osteoderms B-keratin is similar to the one of ornithodiran filaments, also since modern pseudosuchians common characteristics with other "reptiles" like petiolethermy are a secondary acquisition could the "scaly/osteodermic" also is a secondary character and basal members might have been feathery/fuzzy as well?
As many times in science answering a question brings up many more, and this will be the scenery after Yang et al, (in press.), we answer the question is feathers are an ancestral trait for dinosaurs only to open space for the question if it is an ancestral trait of Archosauria. 2018 was not the most vibrant year of paleontology but ending the year with this new amazing paper is very nice and may be a good sign for 2K19.
References:
YANG, Zixiao et al. Pterosaur integumentary structures with complex feather-like branching. Nature Ecology & Evolution, v. 3, n. 1, p. 24, 2019.
DALLA VALLE, Luisa et al. β‐keratins of the crocodilian epidermis: composition, structure, and phylogenetic relationships. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, v. 312, n. 1, p. 42-57, 2009.
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