In 1996, researchers at the University of Adelaide made an extraordinary discovery. Koalas have fingerprints nearly identical to humans. Even under an electron microscope, experts struggle to tell them apart. Koala fingerprints are so similar to human fingerprints that they can taint crime scenes.

Aside from Great Apes, including humans, koalas are the only other species we know of that had unique individual fingerprints. This is pretty outside the box when you realize that around 100 million years of evolution separates the Great Apes and our marsupial koalas. Even with careful, microscope analysis, forensic experts can find them hard to distinguish from human prints. Just like humans, each koala has a unique fingerprint, and they are one of the few non-primate mammals to have them. They are an example of convergent evolution, likely developing to help koalas securely grip eucalyptus trees and handle food.