In Australia, the debris-throwing octopuses were first captured on camera.
There can be some interesting sporting events when there are eight arms (just check out the weird history of octopus wresting). But if facing off against a 100-pound, multi-armed sea monster wasn’t terrifying enough, picture having eight arms that are hurling seashells at you. For the first time, a study revealed that octopuses intentionally hurl detritus like silt and shells, sometimes in the direction of other octopuses, in the open-access journal PLOS ONE.
The gloomy octopus (Octopus tetricus) was observed in Jervis Bay in southeast Australia in 2015 and 2016 using underwater cameras operated by a team of scientists from Australia and the United States. The bay is home to the whitest sand in the entire globe, the tiniest penguin species on the planet known as fairy penguins, marine animals, and a large number of cephalopods.
Professor of marine biology David Scheel from Alaska Pacific University and research author says, “Our study came from the concentration of octopuses at this site, which was unique.” When there are numerous animals present, interactions between octopuses happen often, so this location offers the exceptional chance to investigate behaviors that octopuses bring to bear on interacting with members of their own kind in addition to mating.
The scientists detected 102 instances of trash tossing activity in a group of roughly 10 octopuses after reviewing 24 hours of video spanning several days. There were times when it was difficult to identify the attackers specifically.
The octopuses used a siphon, a tube-shaped device above its legs that can spew water, to launch the missiles after gathering grit from the ocean floor or shells. The material was moved through the water and between their eight arms using the siphon.
The octopuses had to adjust their siphon into an unusual position in order to throw the projectiles, which were frequently launched several body lengths distant. This challenge shows that the throwing technique was distinct from what they would normally do to maneuver around the water.
According to Scheel, throwing things that have been orientated by the thrower is an uncommon animal action. This behavior is made even more startling by the fact that doing it underwater, even for a short distance, looks particularly rare and difficult to accomplish.
Both men and women were seen throwing, however women made 66 percent more throws than men. In or near contacts with other octopuses, such as arm probes or mating efforts, about half of the throws took place. It’s not too shabby for a critter that lives underwater and lacks opposable thumbs or rotator cuffs when about 17% of throws seen strike other octopuses.
Octopuses may alter their skin tone in addition to their cool arms, with dark hues typically denoting anger. The researchers discovered that octopuses with darker coloring could throw with more force and were even more likely to hit another octopus.
The octopuses struck by the substance, however, were not wholly defenseless. They frequently changed their behavior by dodging or elevating their arms towards the thrower’s direction.
“To the best of our knowledge, octopuses have never been observed throwing; therefore, the discovery of their throwing at other octopuses is novel. Octopuses are mostly solitary creatures. This seems to be yet another attempt on their part to control interpersonal interaction, according to Scheel.
Although the scientists acknowledge that it is challenging to pinpoint the precise intent behind this shell-chucking, the observations imply that octopuses are occasionally capable of making targeted throws at other people. Only non-human creatures like chimpanzees, capuchin monkeys, elephants, and birds have been seen to exhibit this complex behavior in the past.
The authors stated in a joint statement that “wild octopuses project various kinds of material through the water in jet-propelled ‘throws,’ and these throws occasionally hit other octopuses.” There is some proof that some of these throws that hurt other people are socially motivated and targeted.