© 2025. The Trustees of Indiana University
Copyright Complaints
1229 East Seventh Street, Bloomington, Indiana 47405
News, Arts and Culture from WFIU Public Radio and WTIU Public Television
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations
Federal funding for public media has been eliminated — we need your help to continue serving south central Indiana
Some web content from Indiana Public Media is unavailable during our transition to a new web publishing platform. We apologize for the inconvenience.

Koalas Have Fingerprints, Too

The fingers of koalas have ridges that look remarkably like a human’s, even though some technical differences are plainly visible. (Benjamint444, Wikimedia Commons)
The fingers of koalas have ridges that look remarkably like a human’s, even though some technical differences are plainly visible. (Benjamint444, Wikimedia Commons)

Common knowledge states that every person‘s fingerprint is unique. While this has never been strictly proven, there‘s something special about the whorls and ridges at the ends of our fingers. After all, who doesn‘t want to be one of a kind?

It‘s not exactly true, however, to say that when it comes to fingerprints, humans are exceptional. Way back in time, as the ancestors of the human race developed, they needed to be able to grab an object, such as fruit, and maintain their hold. Grasping required a hand and fingers that could accurately exert pressure and use fine motor control. It also required traction. As a result, fingertips! The ridges, whorls, loops, and arches created an organized skin surface that could precisely grab things and hold on tight.

It‘s no surprise, then, that fellow primates, such as chimpanzees and gorillas, also have unique fingerprints. But what is surprising is that koalas have fingerprints, too. Looking at koalas‘ fingers and toes, scientists at the University of Adelaide, Australia, found ridges that look remarkably like a human‘s, even though some technical differences are plainly visible.

So why would koalas--marsupials from a different branch of the evolutionary tree than our primate ancestors--have raised ridges on the pads of their fingers, just like we do? And why would the close relatives of the koala, including wombats and kangaroos, lack fingerprints? The scientists suspect that the cause is, once again, that need to grasp. Koalas, unlike wombats and kangaroos, eat by grabbing eucalyptus leaves and bringing those leaves to their mouth. As with humans, all that grasping after tasty food meant that koalas eventually evolved fingerprints.

Sources and Further Reading

Common knowledge states that every person’s fingerprint is unique. While this has never been strictly proven, there’s something special about the whorls and ridges at the ends of our fingers. After all, who doesn’t want to be one of a kind?

It’s not exactly true, however, to say that when it comes to fingerprints, humans are exceptional. Way back in time, as the ancestors of the human race developed, they needed to be able to grab an object, such as fruit, and maintain their hold. Grasping required a hand and fingers that could accurately exert pressure and use fine motor control. It also required traction. As a result, fingertips! The ridges, whorls, loops, and arches created an organized skin surface that could precisely grab things and hold on tight.

It’s no surprise, then, that fellow primates, such as chimpanzees and gorillas, also have unique fingerprints. But what is surprising is that koalas have fingerprints, too. Looking at koalas’ fingers and toes, scientists at the University of Adelaide, Australia, found ridges that look remarkably like a human’s, even though some technical differences are plainly visible.

So why would koalas—marsupials from a different branch of the evolutionary tree than our primate ancestors—have raised ridges on the pads of their fingers, just like we do? And why would the close relatives of the koala, including wombats and kangaroos, lack fingerprints? The scientists suspect that the cause is, once again, that need to grasp. Koalas, unlike wombats and kangaroos, eat by grabbing eucalyptus leaves and bringing those leaves to their mouth. As with humans, all that grasping after tasty food meant that koalas eventually evolved fingerprints.

Stay Connected
Walker Rhea has a B.A. in Comparative Literature from Indiana University. In addition to reading and writing about science, he enjoys performing live comedy in Bloomington, IN and studying dead languages.