Watch Cuttlefish Brawl Over a Mate in Unprecedented Video

Cuttlefish are known to get pretty aggressive, but a newly surfaced video catches a fight over a female in action. Mirko Zanni/WaterFrame/Getty Images

It's usually considered pretty rude to steal someone's romantic partner. But how one deals with that slight varies. Some might Facebook stalk the transgressor. Some might cause a dramatic scene in public. And some might spurt ink and dramatically darken their stripes to scare off the evil Lothario who stole their love.

OK, a human obviously wouldn't choose the last strategy — but a cuttlefish would. While it might sound like a pretty natural reaction to a love triangle for a mollusk, researchers are excited because they've captured the aggressive behaviors of the marine animal in the wild on video for the first time. A recent article published in the journal The American Naturalist analyzes the encounter, filmed in 2011 in the Turkish Aegean Sea. Cuttlefish aggression and fighting have been observed in lab settings, but it's important to study how the animals interact with each other in their natural habitat.

Not to mention cuttlefish belligerence is totally worth watching. In the video, two common European cuttlefish (Sepia officinalis) males start off shooting angry streams of ink and attempting to shoo each other away from the female with an outstretched arm. (Cuttlefish are related to octopuses and squid, and have eight arms.) Before long, however, the males' zebra stripes become more vivid, signaling escalated aggression, and then a rollicking fight ensues, complete with wrestling and biting. Watch the video below to see the tussle for yourself:

This footage is thrilling because it confirms that the aggressive behavior was based on mutual assessment rather than self-assessment, when applying game theory models. That means that the cuttlefish didn't determine their actions based on only their own strength, but on the capabilities of their sparring partner, too. That takes a bit more thought than simply throwing brawn around. Considering this analysis, the discovery might prove to be a valuable way to learn more about the cognition and aggression of animals as a whole.