Octlantis: Marine Biologists Discover Underwater City Of Gloomy Octopuses With Complex Social Behaviors
Octopuses are known to be solitary creatures but a newly discovered octopus city off the coast of Australia suggests that these marine animals are not as isolated and solitary as humans think they are.
Octlantis And Octopolis
The underwater site scientists dubbed Octlantis is found to be home to up to 15 gloomy octopuses (Octopus tetricus), a common species of octopus with an arm span of 6.6 feet.
The site was found in Jervis Bay 33 to 49 feet underwater and lies close to a similar site, which scientists call Octopolis.
When Octopolis was discovered in 2009, scientists thought that the cephalopods gathered there because a human object happened to have formed a central point that the tentacled creatures surrounded with dens.
The discovery of Octlantis, however, suggests that gloomy octopuses did not form a community at Octopolis as a result of the human artifact and that the animals may have been socializing for a long time.
"At both sites, the octopuses engage in frequent and complex social behaviors that are unusual for many species of octopus. The discovery reported here of the second site underscores that the first site was not a unique result of a human artifact that apparently provided the nucleus for the formation of the original site," the researchers wrote in their study, which was published in the journal Marine and Freshwater Behaviour and Physiology on Sept. 1.
Complex Behaviors Observed At Octlantis
David Scheel, of Alaska Pacific University, and colleagues placed four GoPro cameras at the site and recorded 10 hours worth of video that revealed cephalopods communicating, living together, meeting up, as well as chasing away and evicting other octopuses from dens, which are basically holes excavated into shells or sands. Marine biologists found 13 occupied and 10 unoccupied octopus dens in Octlantis.
Scheel and colleagues also observed that the creatures tend to be within an arm's reach of each other and exhibited signs of aggression, mating and chasing.
Researchers said that these behaviors are the products of natural selection and may be similar to the complex social behaviors exhibited by vertebrates. This means that given the right conditions, evolution may lead to similar outcomes in different groups of organisms.
"For these complex behaviors to occur, I think that they must encounter one another and interact regularly over generations, even if at any time there are more octopuses living a solitary life than interacting consistently throughout every day," Scheel said.