Strange Animal Facts - Koala Bears Have Fingerprints Just Like Humans!
Koalas, doll-sized marsupials that climb trees with babies on their backs, have fingerprints that are almost identical to human ones. Not even careful analysis under a microscope can easily distinguish the loopy, whirling ridges on koalas' fingers from our own.
Close human relatives such as chimps and gorillas have fingerprints as well. The remarkable thing about koala prints is that they seem to have evolved independently from the others. On the tree of life, primates and modern koalas' marsupial ancestors branched apart 70 million years ago. Scientists think the koala's fingertip features developed much more recently in its evolutionary history, because its close relatives (such as wombats and kangaroos) lack them.
The fact that primates and koalas separately evolved fingerprints reveals the feature's anatomical purpose. The lifestyles of both koalas and primates require a lot of hand-grasping, both for eating and climbing. It seems that the multidirectional ridges on our fingers evolved to help us grasp.