In the X-Men comics, the superhero Wolverine is armed with three sharp claws on each arm. They extend through the skin of his hand, and the resulting wounds are closed by up his superhuman ability to heal. Now, in a bizarre case of life imitating art, scientists from Harvard University have discovered that a group of African frogs use similar weapons.
The frogs defend themselves with sharp bone claws on their hind feet but to do so, the animals have to drive the claws through their own skin. It's an extreme defence that is completely unique in the animal world.
The clawed frogs belong to a family called Arthroleptidae that were discovered in Central Africa more than a century ago. At first, people wondered if the claws just stuck through the skin as a side effect of the preservation process. Alternatively, the frogs may have used them to grip or ...