We've all seen stories about unlikely animal friendships. They're funny, cute, touching, and sometimes downright bizarre.
Nat Geo Wild even made a TV show about them.
So, why do these unusual bonds happen, and what can they teach us?
Unlikely animal friendships can inform our understanding of the dynamics at play in more normal relationships, said Professor Gordon Burghardt of the University of Tennessee in an interview with the New York Times.
Interspecies bonds are more common among younger animals, among stressed individuals who may learn to depend on each other for comfort, and among those living in captivity. In captivity, animals choose their friends from who's around, and that might mean seeking out a friend in the adjoining pen, whether or not it's a member of the same species.
In an interview with Slate, Marc Bekoff, professor emeritus of ecology and evolutionary biology at the University of Colorado said;
"I think the choices animals make in cross-species relationships are the same as they'd make in same-species relationships...Some dogs don't like every other dog. Animals are very selective about the other individuals who they let into their lives."
Bekoff goes on to observe that predator-prey friendships suggest an enormous amount of trust on the part of the prey animal. And while trust is an important component in certain types of cross-species-friendships, it's by no means the only one.
The emotional connections that animal odd couples forge are as powerful a force as any. According to Anthropologist Barbara King of the College of William & Mary, scientists have observed grief in individuals remaining after a friend of a different species has passed away, such as Tarra, the elephant who mourned the loss of her canine companion, Bella, after Bella was killed by coyotes.
King also points to the incredible example of the bond between Owen the hippo and Mzee, a 100-year old tortoise.
"In this friendship that formed over years, they worked out a system of cross-species communications," King says, using the example to illustrate that the possibility of emotional loss is just as powerful as the risk of becoming prey.
While a number of scientists are on board with the idea that these animal friendships are exactly that, others aren't so sure. University of Arizona psychology professor Clive Wynne, for example, is one of those skeptics. He argues that all of the examples of interspecies friendships he's seen take place "in a human controlled environment."
"To me, that's what kind of removes what would otherwise be interesting...Because it ceases to be directly a story about animal behavior and becomes a story about human impact on the environment," Wynne says.
While there is no doubt that interspecies relationships happen, the nature of these connections remains somewhat unclear. What is certain, however, is that more research is needed to delve into the motivations driving these unusual pairings.
"I think we're not even at the point of being able to extract patterns because the database is so small," says King. She hopes that researchers will begin to collect examples of animal odd couples as a means of building a database extensive enough to subject to scientific scrutiny.
Tell us about some odd animal friends that you know in the comments below!
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