The lions that live in the zoo at Addis Ababa, Ethiopia, don’t look like other lions. They descended from lions once owned by Ethiopia’s late, zoo-founding emperors, and they “have dark manes and small bodies,” National Geographic reports. That’s not so strange, but zookeepers were convinced that these lions were really something special.

And it turns out, they were right:

A team of researchers, led by the Max Planck Institute for Evolutionary Anthropology in Germany and the University of York in the UK, checked to see if the lions really are different by comparing DNA samples of 15 lions from the zoo to six populations of wild lions … Their genetic analysis revealed that the gene sequence of all fifteen lions were unique and showed little sign of inbreeding.

Grist thanks its sponsors. Become one.

The going theory is that lions like these used to live out in the wild, but their manes were so beautifully dark that they were hunted to near-extinction and then captured for display. The zoo lions are the only survivors.