The Surprising Origin of the Fingers
A recently discovered fossil shows that quadruped fingers had partially evolved before vertebrates emerged from the water and roamed the land.
Five fingers starting from the palm: With this arrangement, which combines flexibility with strength, we can play the piano, swing a hammer or caress a fellow human being. No other part of the body is so familiar to us - after all, we use it for most everyday activities, from dressing and driving to cooking and texting. From the point of view of evolutionary biology, however, the hand still holds many a mystery, and this is particularly true in the early stages of its formation. In other four-limbed animals-grouped together in the quadruped or tetrapod group-the hands look and function very differently from ours. Birds and bats, for example, have made cleverly constructed wings out of it; while elephants have limbs the size of tree trunks.
But the basic structure of the hands is always the same. Charles Darwin (1809-1882) wrote about the similarities as early as 1859 in "On the Origin of Species": "What could be stranger than that the hand shaped for grasping in humans, for digging in moles, the horse's leg, the fin of the bottlenose dolphin and the wings of the bat are all built to the same pattern and have similar bones in the same relative positions?"
Darwin provided a plausible explanation for this: All the different animals share this structural principle because they descended from a common ancestor that had limbs with fingers…