Octopus city found off coast of Australia
Octopuses have generally been viewed as lonely creatures.
They are smart, quick and have a remarkable ability to solve problems but they
mostly do all this alone and don’t interact much with other octopuses.
Now, researchers have discovered an underwater ‘octopus
city’ off the coast of Australia and it harbors up to 15 individual octopuses.
In the site, octopuses have been observed interacting and communicating with
each other, suggesting that these deep sea creatures might not be strictly
solitary.
“These behaviors are the product of natural selection, and
may be remarkably similar to vertebrate complex social behavior. This suggests
that when the right conditions occur, evolution may produce very similar outcomes
in diverse groups of organisms.” Lead researcher David Scheel of Alaska Pacific
University told Quartz.
The new site is the second octopus settlement found in the
Jervis Bay area of Australia and researchers have named it Octlantis. The
octopuses found in the settlement belong to a species known as Octopus tetricus
or gloomy octopuses, characterized by white eye pupil and orange-rust arms.
The first settlement, named Octopolis, was discovered in
2009, where more than16 gloomy octopuses were found involved in social contact
besides mating. The site is composed of several dens as well as a human-made
flat object around 30 centimeters long.
The newly-discovered settlement is just few hundred miles
away from the first one and also contains several dens and features similar to
the first settlement. The discovery supports the idea that octopuses can
socialize under certain conditions.
“At both sites there were features that we think may have
made the congregation possible – namely several seafloor rock outcroppings
dotting an otherwise flat and featureless area," said co-researcher
Stephanie Chancellor from University of Illinois at Chicago. "In addition
to the rock outcroppings, octopuses who had been inhabiting the area had built
up piles of shells left over from creatures they ate, most notably clams and
scallops. These shell piles, or middens, were further sculpted to create dens,
making these octopuses true environmental engineers."
Researchers came to that conclusion after diving to the
place and recording several hours of footage with GoPro cameras. In the
footage, researchers witnessed mating, chasing, signs of aggression and other
signaling behavior in octopuses. While little is known about the solitary lives
of octopuses, a few octopus settlements with multiple individuals interacting
socially have been found in recent years.
"Animals were often pretty close to each other, often
within arm's reach. Some of the octopuses were seen evicting other animals from
their dens. There were some apparent threat displays where an animal would
stretch itself out lengthwise in an 'upright' posture and its mantle would
darken. Often another animal observing this behavior would quickly swim
away…but we still don't really know much about octopus behavior.” said Chancellor.
“More research will be needed to determine what these actions might mean.”
