In an upcoming paper for the journal Aquatic Mammals, a pair of scientists detail a series of interactions between an adult bottlenose dolphin with scoliosis - "highly pronounced curvature of the spine " - and a group of sperm whales in the Azores. The scientists describe their research as the first time sperm whales have been observed interacting in a non-aggressive way with a member of a different species.
In other words: They repeatedly spotted a dolphin with a messed up back hanging out with a group of sperm whales.
The paper's authors, Alexander Wilson and Jens Krause, write that the whales treated the dolphin as a "conspecific" - a member of the same species - "at times both permitting and initiating physical contact." They also say that the interactions went beyond "simple tolerance."
"Initially, we thought it was a very unusual interaction as sperm whales are not known to show non-aggressive behaviors to other species of cetaceans, however at this point we thought it might just be a one-off unusual interaction," Wilson told Weather.com. "When some time afterwards we saw the same dolphin still interacting with the same or other sperm whales, we thought there must be some underlying mechanism...beyond the animals simply being in the same place at the same time."
They posit and reject several possible reasons for the odd affiliation, before suggesting a couple very sweet possibilities.
"What we did see," Wilson says, "is a lot physical interaction between the dolphin and the whales and the interactions seemed to be the same kind of interactions seen between sperm whales themselves." Ultimately, they hypothesize that, according to Wilson, "it could be a form of social 'play' or it could be that the sperm whales interpreted the dolphin as being another sperm whale calf."
Either the whales just like playing with the dolphin or they've adopted it.
Wilson also noted that while the behavior was extremely unusual for sperm whales, it "is not so unusual for dolphins, they are very gregarious and readily interact with many species including people!"