Why did Tyrannosaurus rex have such short arms? |
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What did the T. rex use its little arms for? – Aurora, age 11, Pemberton Township, New Jersey
What did the T. rex use its little arms for? – Aurora, age 11, Pemberton Township, New Jersey
One of the most famous dinosaurs to ever roam across Earth, Tyrannosaurus rex, has filled people’s minds with wonder since the first skeleton was discovered in the early 1900s.
Scientists believe T. rex, or King of the Tyrant Lizards, as its name translates, was a fearsome predator. An adult T. rex was massive in size – approximately 40 feet (12 meters) long and 20 feet (6 meters) tall, weighing as much as an African elephant. Each of its enormous sharp teeth could be near a foot (0.3 meters) in length from the root to the tip.
I’m a paleontologist, and I use fossils to study how animals lived and evolved over long periods of time. One of the coolest things about being a paleontologist is that there are always new questions to ask and new things to learn – even about a super-well-known dino like T.rex, which went extinct just over 65 million years ago.
One T. rex mystery has to do with this giant predator’s relatively tiny arms. Why would it have arms so short that it couldn’t even reach its own mouth? How did it use them?
How ‘short’ is short?
First, let’s define what we mean by “short.”
The biggest T. rex could measure 45 feet (14 meters) from the........