Why did T. rex have tiny arms?

1. 1

   Tiny says

   A grown-up T. rex was about twelve metres long from nose to tail, but its arms were only about one metre long. Tiny next to that giant body, just like mine! So what were they for? Scientists still aren't sure, and they're working hard to find out.

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   Checked against How did Tyrannosaurus rex use its arms? (Natural History Museum)

2. 2

   Then why did its arms get so small?

   Big meat-eating dinosaurs from other families grew short arms too. Each time, their heads and jaws grew big and strong, so their jaws may have done the grabbing instead. It's a good idea, but nobody has proven it yet.

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   Checked against New dinosaur species reveals short arms evolved repeatedly in theropods (Natural History Museum)

3. 3

   So could those little arms do anything?

   Scientists have a few ideas. Maybe T. rex used them to push itself up off the ground after a rest. Or maybe short arms stayed safely out of the way when lots of T. rex shared one big meal. Nobody has proven either idea yet, so the mystery is still open.

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   Checked against New dinosaur species reveals short arms evolved repeatedly in theropods (Natural History Museum)

In Lil' Phil, reaching the bottom of this wonder earns a sticker for Tiny's collection.

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