The conger eel was the favourite, weighing not less than 3 times greater than its eight-armed opponent. However by the point the video footage begins, the underdog octopus had already asserted its toughness, blocking the eel’s eyes and stuffing arms into its mouth and out the gill gap.
“I assumed that with such distinction in measurement it could be exhausting for the octopus to keep away from loss of life,” stated Jorge Hernández-Urcera, a marine ecologist on the Institute of Marine Analysis of the Spanish Nationwide Analysis Council.
The frequent octopus not solely defended itself, but additionally appeared to return out on high. The divers who made the video — not scientists — broke up the brawl, and the 2 animals survived, the octopus tearing off in a cloud of ink.
“It was very spectacular to see,” stated Dr. Hernández-Urcera, who collects novice diving movies and analyzes them for beforehand undescribed habits. He believed this video, recorded in 2008 off the coast of Galicia in northwestern Spain, confirmed “the intelligence of octopus and the massive repertoire of defensive habits.” Nevertheless it was solely a single video, not sufficient to recommend that this eight-armed method was a daily type of octopus martial arts.
Extra just lately, Dr. Hernández-Urcera acquired extra video footage. Sufficient, he believes, to indicate that octopuses will choke, blind and sacrifice limbs in an effort to defend themselves from a lot greater eel foes. He revealed his analysis in March within the journal Ecology and Evolution.
On this 2022 video, taken off the coast of the northern Spanish area of Asturias, one other frequent octopus makes use of the identical ways seen within the first video to defend in opposition to a conger eel assault. In response, the eel quickly spins to get free. At this level the octopus escapes, nevertheless it manages to come out one of many eel’s eyeballs with the ability of a sucker.
In every video, the frequent octopus might sacrifice arms, a lot as lizards drop their tails to distract predators, Dr. Hernández-Urcera stated. Within the first video, the octopus loses three arms whereas the one within the second video loses two — however they will totally regrow limbs in about 45 days, some lab checks present.
The octopus doesn’t all the time win. In a 3rd video, taken in 2023 close to Galicia once more, the conger eel grabbed the cephalopod from the pinnacle, then spins the octopus round in a loss of life maintain, slamming it onto rocks. The octopus seems shocked, if not lifeless, after which the eel swims off with its prey.
Piero Amodio, a biologist and comparative psychologist with the Anton Dohrn Zoological Station in Naples in Italy, thinks that when plugging the eel’s gills, the octopus’s arms might function instinctually — actually with a thoughts of their very own due to the various neurons of their appendages.
“My hunch is that the arms can do this in a non-completely aware manner,” Dr. Amodio stated.
He stated he had seen fights between octopuses the place one will fill the gill gap of the opposite with an arm, asphyxiating its foe.
Peter Tse, a professor of cognitive neuroscience who works with octopuses at Dartmouth Faculty, calls it a “outstanding adaptation” and factors to a scene within the documentary “My Octopus Trainer,” the place an octopus resists an assault from a shark by climbing onto the again of its head.
“If it’s not an intuition however one thing that they consider individually, it’s much more outstanding,” Dr. Tse stated, “as a result of it takes fairly a little bit of perception to know that the one solution to escape this mouth is to get behind it.”
Dr. Hernández-Urcera isn’t certain whether or not the combating strategies in his movies are instinctual or realized habits. However that’s partly as a result of conger eels usually hunt at evening, whereas these movies have been taken within the day. He believes these encounters might occur regularly.
“We predict from the start of their lives,” he stated, “octopus should face these sorts of assaults from conger eels.”