So far, Druckenmiller and his team have dug up species from seven different dino families: from big duck-billed dinos, ceretopsians, and tyrannosaurs to smaller thescelosaurs, leptoceratops, dromaeosaurs, and troodontids.
We now know that juvenile tyrannosaurs were much slimmer and lightly built than the adults, with arms slightly more in proportion with the rest of their body.
Falcarius shared an environment with a host of dromaeosaurs, troodontids, and early tyrannosaur relatives, so competitive pressure among carnivores was likely pretty high.
Even though there's no direct evidence of feathers on T. rex, there's a good chance the tyrant king was at least a little fluffy, because other tyrannosaurs have been found with protofeathers.
If euplocephalus swings its tail at a tyrannosaur like gorgosaurus, but the tail snaps in half, then that would cause a lot of trouble for euplocephalus.