Deep in the Indonesian rainforest, a small step for a wild orangutan and a giant leap for our understanding of how alike we are to nonhuman primates. That's where researchers say Rackus, a male orangutan in his 30s, was injured in a fight back in 2022. The team documenting this quarter-sized wound under his right eye and another in his mouth. Dr. Isabella Laumer, a behavioral biologist and one of the studies lead researchers, says they followed the orangutan to observe what he would do and were astounded to see him chewing the leaves of the liana plant.

So it's quite rare that they eat from it.

Known to local humans for its pain relieving properties. The researcher's findings published this week in the journal Scientific did not end there. They then spotted Rackus using the plant to make a paste from the crushed leaves and sap and applying it to his facial injury, marking the first time an animal has been seen using medicine to treat skin wound. This discovery adds to growing research suggesting animals may self-medicate with varying degrees of sophistication. The researchers with the Max Planck Institute say this behavior could even be traced back to a common ancestor between humans and other primates. Does this tell us anything about our own connection to these nonhuman primates?

I mean, it also shows, again, how similar great apes are to us. So we share 97% of our DNA with orangutans.

They say Racky's medicinal treatment may be his own innovation, or more intriguingly, something he learned culturally from other orangutans earlier in life.

Sometimes they also watch from a distance, but sometimes they go super close, sometimes even up to 20 centimeters, and watch the other doing something.

And Rackus's treatment worked. The researchers say his wound never showed any signs of infection and closed up within a week. The fascinating finding, giving for thought on how similar we are to our primate cousins.

It really is so important to create more protected forest areas for these animals. It would be so sad to have these wonderful, astonishing animals leave this world.

Stephen Romo, BBC News.

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