Researchers from Australia, the United States, and Canada have studied videos of octopuses in the wild, finding that females were generally more likely than males to shed things .
In the videos, they use the arms and the water jets of the siphon in a coordinated way, sometimes hitting other octopuses.
Attempted rape
In most cases, this throwing material gesture served to move material around, for example to remove food waste or other excess materials, but they also observed that it sometimes had a different purpose: they wanted to drive away a nearby male .
Female octopuses use this strategy to avoid forced copulations: perhaps speaking of "rape" is too emotionally charged that cannot be found in the animal kingdom. But there is no word that describes forced copulation between nonhumans, so it is used regardless.
In one case, in December 2016, a single female octopus threw material on ten occasions and on five of them hit a male , as described in the study (preprint) that has been published on the matter. As the researchers explain:
The force does not come from the arms, as in a human launch, but rather these limbs prepare the projection of the material, which will then be propelled by the jet. In general, the release is seen more frequently in females. And, in fact, we have only seen a marginal repulsion launch in a single male.
We have a new pre-print up about octopus behavior. Octopuses throw debris, sometimes hitting others; do they intend to? https://t.co/l2yhD8IlD3 The paper has not been peer reviewed. Work with David Scheel, Stephanie Chancellor, Stefan Linquist, & Matt Lawrence. [1/3] pic.twitter.com/QhpfNnR1kU
– Peter Godfrey-Smith (@pgodfreysmith) August 27, 2021
Throwing objects is not a common behavior in animals, although chimpanzees, capuchins, elephants, mongooses, and birds have been known to do so. Actions related to throwing have also been observed in other animal species, such as the movement of irritating hairs by spiders and the jet of water by archerfish.
Throwing objects, thus, is generally considered as a specifically human action and one that played an important role in our evolution.