Passage Summary: Scientists used to think T-rex's weird body shape was an adaptation for being huge, but the discovery of a tiny dinosaur with the same shape suggests that size might not be the reason for those traits.

Conclusion: The theory that T-rex's physical features evolved specifically to handle its massive size and weight is incorrect.

Reasoning: A much smaller and lighter dinosaur was discovered that possessed the exact same physical characteristics as the T-rex.

Analysis: The argument relies on the idea that if a small creature has the same traits as a large one, those traits couldn't have been 'for' managing large size. To evaluate this, we need to know the relationship between these two species. If the small dinosaur is a direct ancestor, it suggests the traits evolved first for a different reason. We should look for an answer that asks about the evolutionary link or the specific function of those traits in the smaller specimen to see if the 'size-accommodation' theory truly needs to be abandoned.