Researchers from Australia, the United States, and Canada have concluded that female octopus sometimes throw objects such as shells, rocks, and even algae at males when they approach to mate.
Six years ago the same team recorded several attacks by octopuses, but it was not clear if they were done voluntarily or accidentally. Now they have confirmed their suspicions through recordings made with GoPro cameras in an area where many of these animals live, more specifically in Jervis Bay, in South Wales, Australia.
In the recordings it was clearly seen how the female octopus threw objects and that they did so for two reasons. The first was as part of “housework” , to keep their shelter clean of waste and food scraps. The second, however, had a very different reason and that is that the throws were made against the male octopus, in an attempt to repel them to prevent them from mating with them .
And how do female octopus get to throw objects? At first it may be thought that the throws are made with the arms, but this is not the case . “The force does not come from the arms, as in a human launch, but these extremities 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 release in a single male ”, the researchers point out in the publication, made in bioRXiv and that will still have to go through the peer review process.
The researchers note that when females throw objects for males to leave them alone, they can do so repeatedly. So much so that in 2016 a case was documented in which a female octopus threw material at a male 10 times over a period of 3 hours and 40 minutes, hitting him five times. Interestingly, the octopuses that were hit with such ejections made no attempt to retaliate, but sometimes tried to duck so they wouldn’t get hit (not always successfully). Another, perhaps somewhat more controversial, explanation for this behavior could be that the throws are not necessarily always directed, but could be a form of frustration tantrum.
“Octopuses can thus be definitively added to the short list of animals that regularly throw or propel objects, and provisionally to the shorter list of those that target other animals,” the researchers write. The funny thing is that the attacks are aimed at members of their own species, the less common form of non-human launch.
Other animals capable of throwing objects are chimpanzees, capuchin monkeys, elephants, mongooses, and birds.
Fuente: In the Line of Fire: Debris Throwing by Wild Octopuses; Peter Godfrey-Smith, David Scheel, Stephanie Chancellor, Stefan Linquist, Matthew Lawrence; bioRxiv 2021.08.18.456805; doi: https://doi.org/10.1101/2021.08.18.456805.
