Posted: Sep 24, 2018 10:01 pm
by theropod
Wortfish wrote:
theropod wrote:Extant birds do not use their femur in the same way that nonavian dinosaus did. If the chicken video were of a chicken skeleton, and a side by side gate with the T. rex skeleton were shown, the difference would be obvious. The T. rex femur could be seen to swing across a far wider arc than the femur in any extant bird. While the chicken and tyrannosaur both employ their feet in similar manners there is a subtle difference here as well. Chickens have a descended and expressed hallux (rear facing digit) which bears weight, whereas tyrannosaurs rarely left traces where this digit is seen because it is greatly reduced. This means the tyrannosaur could not easily tilt back on its feet without balance issues. Think of T. rex as being shark-like, and moving forward most of the time.

RS


Do you think the T-Rex was covered in feathers?


What I think and $5 will get you a cuppa. What matters is what evidence exists. Since so many basal dinosaurs have been found with associated feathers, or quill scarring from where feathers were anchored, it becomes quite possible to infer all dinosaurs retained some form of feather. Ornithischians, as well as Theropods, have now been recovered which reveal the preservation of feathers. The environment in which feathers are preserved is critical for such evidence to survive across such deep time. In a Laggerstatton setting requires a lake deep enough, and stable enough, to create an anoxic at, or near, the sedimentary layer. The subject specimens must arrive at this layer largely intact, and remain undisturbed until lithification.

In some settings, like the ocean fronting Hell Creek, which was a lowland forest with slow meandering streams, which changed course with each new tropical storm. Such a setting, which is where we find specimens of Tyrannosaurus rex, is not conducive to feather preservation. I suspect T. rex did have feathers in some form, as did all dinosaurs. Even such armored critters as Ankylosaurs could have had feathers. Think guard hairs used as touch sensors. Having a suit of armor would isolate an Ankylosaur without some means by which to detect immovable objects, and a few well placed quills and they could be nimble in thick cover.

All this, and so much more, can be researched using Google Scholar. Don’t ask me these questions. Ask what the evidence shows. Ask using one of the greatest educational tools ever created, and is at your fingertips. Ask what we have discovered, and how we have done so, and then you can ask questions of the right kind. My opinion, as is yours, or anyones, is worthless in comparison to hard empirical evidence.

RS