Uploaded October 2025 | Updated September 2026, 2 weeks ago

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T. rex makes you question both evolution and your gym routine. But why were their arms so small? One scientist thinks it’s so they didn’t accidentally get bitten off by other dinos.

Learn more from Britannica: britannica.com/animal/Tyrannosaurus-rex
Dr. Padian: https://ib.berkeley.edu/people/faculty/padiank
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