Scientists collected dolphin urine, dumped those samples into other dolphin enclosures, and then recorded how long they spent investigating the pee. Yes, really. It’s part of a study to understand how dolphins recognize each other. Along with whistles specific to each individual, apparently urine plumes are a way to find friends.

And just to add to the fun, dolphins taste everything because don’t have a sense of smell. So of course they sampled the pee with their mouths. The scientists used bottlenose dolphins living in captivity at Dolphin Quest in this study. They are trained to voluntarily give urine samples in exchange for treats.

Bottlenose dolphins at Dolphin Quest showed they recognize each other's urine
Flickr/R’lyeh Imaging

The peer-reviewed journal Science Advances published the research, which we saw at The Guardian. The dolphins spent three times as long smelling the pee of familiar dolphins than unfamiliar ones. The scientists also played the whistle equivalent of the urine donor’s name. When that happened, the dolphins were more interested than when the whistle and the pee didn’t match up.

So why would this be? Bottlenose dolphins live in social groups in the open ocean. Communicating via whistles can help keep those groups together. Apparently, they may also use urine plumes. If a dolphin is lost, it could taste familiar pee in the water and join back up with their group. 

I feel like I know too much about dolphins now. Their sexual behaviors are also a focus of scientific research. I just want to go back to the days when dolphins would hang out with dogs or have pure interactions with sloths. Then again, The Deep’s dolphin scene from season 1 of The Boys is one of the best of the entire series. 

Melissa is Nerdist’s science & technology staff writer. Her Patronus is a dolphin, but now that doesn’t seem like such a good thing. Melissa also moderates “science of” panels at conventions and co-hosts Star Warsologies, a podcast about science and Star Wars. Follow her on Twitter @melissatruth.