Of all the animals kept in aquariums around the world, one always stands out. The jellyfish, the sharks, the skates, the giant sea bass, and the clownfish—they’re beautiful and often impressive, sure, but in the end, behind their glass enclosures, they’re basically moving wallpaper. There’s only one creature that knows everything that’s going on, watches everyone who walks by, and judges it all.
The giant Pacific octopus is both my favorite and least favorite animal to visit at the aquarium. I think cephalopods are fantastic, and octopuses in particular have long been a particular fascination of mine, and the culture at large. But it’s also been clear to me every time I’ve seen one in captivity that it knows it’s being held hostage. When they choose to come out, giant Pacific octopuses don’t just swim around doing their normal octopus things—they perform. Then they disappear again, away from the prying eyes of school field-trip groups and couples on dates.
The giant Pacific octopus is a master of deception. It play-acts, it camouflages, and it disappears into seemingly impossibly small crevices. Is it any surprise, then, that we know so little about the animal?
In fact, we know so, so very little about the giant Pacific octopus that it turns out to have actually been two species of octopus this whole time. Recent research from Alaska Pacific University has revealed that some number of giant Pacific octopuses are actually frilled giant Pacific octopuses. Earlier this week, Earther reported on the discovery, noting that the new species had been “hiding in plain sight.” Maybe it was more of a deliberate move of deceit on the part of the octopuses, and not so much a failing of human scientists’ investigative skills.
During the Alaska Department of Fish & Game shrimp surveys of 2012 and 2013, David Scheel, a marine biologist at Alaska Pacific, and Nathan Hollenbeck, an undergraduate student at the school at the time, collected 21 live octopuses that were snared as bycatch in shrimp pots. 14 of them were clearly giant Pacific octopuses, Enteroctopus dofleini, but the remaining seven were… different. These outliers looked kind of like the others, but they had frills all over their mantles. The seven strangers also had strange eyelash-like protuberances, and two white spots on the front of their heads, whereas the typical giant Pacific octopus has only one.
The researchers took a swab of epithelial cells—the cells that make up the tissues that line the cavities and surfaces of body organs—from the octopuses, and took them back to the lab for genetic testing. The tests confirmed that, indeed, these seven cephalopods were genetically distinct from the giant Pacific octopus in the scientific literature.
So far, according to Earther, Hollenbeck and Scheel have only spotted the frilled giant Pacific octopus in waters ranging from Juneau to the Bering Sea. In comparison, their non-frilled genetic cousins have been spotted all over the northern Pacific Ocean, from the western coast of the lower 48 states of the US, up to Alaska, and all the way across the sea off the coast of Japan.
That said, the giant Pacific octopus is well-known to be a master of disguise, and scientists admit they don’t have a strong grasp on their behavior—to the point where we really have no idea how many of them are out there. In addition, marine biologists and ecologists have long suspected that the giant Pacific octopus might actually be better thought of as an umbrella term encompassing a bunch of different species. So who knows? Perhaps there are plenty of frilled giant Pacific octopuses—which have not yet been given an official Latin taxonomic name—and we just have been fooled this whole time.