Whats the scientific opinion about Dinosaurs and feathers? Did all dinosaurs have feathers or did they only had feathers at the end of the cretaceous period?
Thread for discussion of paleontology, paleo art, geology, biology, etc. I have recently become interested in this topic and would like to learn more.
Oculudentavis khaungraae was described in March 2020 as an avialan dinosaur. Then the original paper was retracted by Nature when it was shown to be a lizard (following the discovery of a second specimen). But the name & description are still valid according to the ICZN. So now further work will have to cite a retracted paper. It’s unclear why the retraction occurred since incorrect phylogenetic placement is usually not met with such a severe measure. It’s possible the provenance of the fossil (from controversial Burmese amber) was a significant factor in this decision.
Original paper here (retracted):
https://sci-hub.tw/downloads/2020-03-16/10/xing2020.pdf
My understanding is that the evolutionary origin of feathers is still an area of debate and active research. For example, apparent integumentary appendages in ornithischian and pterosaur fossils have been interpreted as feathers; if these structures are homologous with theropod feathers (and not convergent), this would suggest that feathers evolved deep in the archosaur lineage, perhaps during the early Triassic. However the preservation in these fossils is generally incomplete so this view is disputed.
Fun fact: certain extinct relatives of crocodiles such as basal crocodylomorphs from the Triassic were gracile and terrestrial, with long slender limbs and an erect gait like that of mammals or dinosaurs. In fact some paleontologists even believe endothermy evolved early in the crocodile lineage and was secondarily lost, based on several lines of evidence such as comparative anatomy and bone histology of fossil specimens.