Frozen_Heart
Hero
All dinosaurs (and pterosaurs) shared a common ancestor which was covered in fuzz. However many groups lost their feathered covering over time and switched to scales. Which groups have feathers and which have scales seems to be a bit all over the place. Every time a scaled animal is found, a close relative is found with feathers. And every time we think a group is feathered, another relative is found with scales.Do we know if all Dino's had feathers? Or just some types?
Larger species such as hadrosaurs, ankylosaurs, sauropods, ceratopsians, and many theropods all seemed to have had scales though. Smaller species seemed to be more likely to have fuzz of some sort. The environment would also play a factor, with species in colder climates probably being more likely to have coverings of some sort.
Complex branching feathers which we think of on modern birds are unique to more derived theropods though. Raptors, birds, and maybe ornithomimids.
Animals can lose or gain a fluffy covering in a relatively short time period. Elephants and mammoths are extremely closely related, yet one have tough and thick bare skin, while the other has long and dense fur.