Scientists discover second octopus city, population 15

Octopodes were long considered solitary creatures, but the discovery of a second seafloor dwelling with over a dozen inhabitants has scientists rethinking the social behavior of these little sea-geniuses.

Via Quartz:

The international team of marine biologists, led by professor David Scheel of Alaska Pacific University, filmed these creatures exhibiting complex social behaviors that contradict the received wisdom that these cephalopods are loners. Their study was published in the journal Marine and Freshwater Behavior and Physiology (paywall).
The discovery was a surprise, Scheel told Quartz. "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."

They dubbed the first underwater "octopus city" off the coast of Australia in Jervis Bay "Octopolis," and they've named this second one "Octlantis."

Scientists discovered a never-before-seen octopus 'city' — and they named it 'Octlantis' (YouTube / Tech Insider via Quartz