According to a study led by Peter Godfrey-Smith at the University of Sydney and colleagues and published on November 9, 2022, in the open-access journal PLOS ONE, octopuses appear to actively hurl trash, sometimes in the direction of other octopuses.
Researchers recorded the behavior of gloomy octopuses (Octopus tetricus) in Jervis Bay, Australia in 2015 and 2016 using underwater video cameras. Although individual identification was not always possible, they were able to find 102 instances of debris throwing in a group of about 10 octopuses after studying 24 hours of video over many days.
Octopuses gathered debris like silt or shells and threw it while utilizing a jet of water from their siphon (a tube-shaped device that can discharge water at high speeds) to drive it through the water and between their arms, frequently tossing stuff several body lengths away.
Octopuses had to adjust their siphon into an unusual position in order to conduct the throws, indicating that the activity was intentional. Although both sexes were seen throwing, 66% of throws were made by women.
Wild octopuses project various kinds of material through the water in jet-propelled ‘throws,’ and these throws sometimes hit other octopuses. There is some evidence that some of these throws that hit others are targeted, and play a social role.Peter Godfrey-Smith
About 17% of throws hit other octopuses, and about half of throws happened during or right after contacts with other octopuses, such as arm probes or mating attempts.
Dark skin tones are typically associated with aggression in octopuses, and the researchers discovered that these creatures tended to toss more fiercely and were more likely to hit another octopus. When an object was thrown towards an octopus, they frequently changed how they behaved by ducking or elevating their arms in the thrower’s direction.
The first time that throwing behavior in octopuses has been documented. The actions seen show that octopuses are capable of throwing objects specifically intended for other people, a behavior that has only been seen before in a small number of non-human creatures, according to the authors, even though it can be challenging to ascertain why they are doing it.
The authors add: “Wild octopuses project various kinds of material through the water in jet-propelled ‘throws,’ and these throws sometimes hit other octopuses. There is some evidence that some of these throws that hit others are targeted, and play a social role.”