Study Shows Manatees Have Brittle Bones

Study Shows Manatees Have Brittle Bones:

"When you pick up a manatee rib, it's much denser than a cow bone or human bone. Most people would think these ribs would be really strong, as they're so heavy. But in fact, they behave like ceramic material," Reep said.

The bones of the endangered sea cows have no marrow cavity, which is why their bones are so dense. But that density makes them more fragile.
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The researchers are using an air gun to hurl a 2-by-4-inch board toward a manatee bone target to reconstruct the ways various forces are distributed through the bone.