The octopuses were found brooding, which is not to say that they were petulant. Rather, most of the creatures had their eight tentacles inverted to protect eggs, and researchers posit that the underwater gathering is made up of females. The eggs were fastened on rocks approximately 10,000 feet below the ocean’s surface.

“I’ve never in my career come across something like this, where these could potentially be nursery habitats,” King said. He speculates that the octopuses are using that area because the rocks there are especially clean or because the waters are warmer. But since so few brooding conventions have been seen, marine biologists really don’t know exactly how to explain the gatherings in this particular location. “We really don’t know much about the deep sea—we’ve seen less than 1 percent of the world’s deep ocean bottoms. On any particular dive you could be shocked by something,” the scientist told KQED.

The cephalopods were identified as the Muusoctopus robustus species. These octopuses don’t have ink sacs and are quite small. They’re considered “cosmopolitan” creatures because they are believed to have originated in the Pacific Northern Hemisphere and migrated throughout the world’s oceans. Now that we know they also gather in large groups  to brood there’s even more reason to consider this particular species of octopus both cultivated and worldly. 

The discovery adds to a growing body of knowledge on octopuses that indicates humans still have a lot more to learn about the exceptionally intelligent creatures. We know now that some octopuses live in a small metropolis researchers dubbed Octlantis, and that there are even scientists who hypothesize that these cephalopods, which evolved long before humans, may even have come to Earth from outer space. One thing is certain, more research is needed to better understand these mysterious sea creatures.

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