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I'm Dr. Kenneth Laoa, paleontologist and executive director of the Edelman Fossil Park of Rowan University, and I'm here to answer your questions from the internet. This is Fossil Support. [Music] Jenny Fly Rocks asks, "Do you know how Tyrannosaur's head is too big for the rest of her? Is it me? " Well, no, it's not you. It has a really big head. It needs a really big head because Tyrannosaur, Tyrannosaurus Rex in particular, had the strongest bite force of any land animal probably ever. And to have a really strong bite, you need a really big skull that can house really big jaw muscles. And it turns out that head muscles and arm muscles compete for attachment space around the girdle of the shoulder. So, as T-Rex's bite got more ferocious, its head got bigger, its neck muscles had to get bigger. It needed to occupy more space on the shoulder for its neck muscles. Its arms got shorter and shorter and shorter. So, those comical little arms that T-Rex has with two little witchy fingers is what made possible its murderous bite. Laura Bedrosian writes, "Can you comment on the science behind extracting dino DNA from mosquitoes and amber? Is that just Jurassic Park stuff? " Yes, it is. Amber is actually a terrible geochemical environment to preserve DNA. people have looked and no DNA from dinosaurs has yet been recovered. It seems to be too old, at least for existing technology and/or samples. Clipped Wings2 writes, "How do fossil bones fossilize? Are they just filled with air or are they somehow filled with the same rock that surrounds the fossils? " The latter, they are filled with the same rock that surrounds the fossils. Here is a fossil terasaur bone from Morocco, its Cretaceous age. You can see that there is sediment inside the hollow bone of the terasaur. And so what usually happens is the same rock that is surrounding the fossil also gets inside the fossil and it's preserved that way. Holton music man writes, "How do fossils for fossil fuel end up 2 miles beneath the surface, especially enough to make oil? " The fossils have to be buried in what we call a depositional basin. Think of a river valley or a continental shelf off of a coastline.