Can someone help me answer these questions!? 6. The first tree used to divide the dinosaur into two separate groups are the structure of their hips. What are the two groups and what do the group names mean?

The two groups are Tyrannosaurus Ornithomimus and Tyrannosaurus Coelophysis which are different from one another in shape and body structure.

The word Ornithomimus means ''bird mimic,” because it resembles the bird i.e. they are toothless and had beaklike jaws while on the other hand,  Coelophysis means 'hollow form' and the specie has hollow limb bones that makes Coelophysis is a lightly body dinosaur that make it a fast hunter.

that is wrong, its not thymus.