What has three hearts, blue blood, a beak, and most of its brains in its legs? David Scheel (M.S. ’86, Ph.D. ’92) knows the answer to that and a lot more. 

A professor of marine biology at Alaska Pacific University in Anchorage, Alaska, Scheel is a behavioral ecologist whose primary interest is predator-prey interactions. His specialty is octopuses. (Yes, that’s the plural, not octopi.) 

“A day when I see an octopus is a good day,” he says. Thanks to his research and that of other scholars, the global reputation of this color-shifting boneless marvel has changed. Once seen, says Scheel, as “a creeping horror of 10,000 sucker-fingers,” the octopus has had a public image makeover. Today scientists know that octopuses pass memory tests, solve puzzles, and learn complex mazes. They use tools. (One species builds homes by assembling split coconut shells.) They recognize individual people, and they play, teasing keepers by squirting water at them.

“I think lay public opinion about octopuses is shifting from ‘nature is horrible’ to ‘nature is fragile,’” says Scheel, whose book Many Things Under a Rock will be published by W. W. Norton in June. “They are one of the most intelligent life forms on the planet. If we want to understand what it would be like to encounter an intelligence from another planet, the best model would be to encounter octopus intelligence.”

Part of the mollusc family, octopuses branched off evolutionarily from all other intelligent species 600 million years ago. “Because the octopus evolved on its own separate track, inventing its own version of an eye, a brain, and a heart, the octopus is a unique expression of evolution. No other intelligent animal on the planet evolved separately from all other animals this way,” he says.

For the past 30 years, Scheel has studied these cephalopods, a class of mollusc that includes squid, from the depths of Alaska’s Prince William Sound to Madagascar and Australia. His most recent paper reveals a surprising discovery about the gloomy octopus (Octopus tetricus), one that is another testament to octopuses’ brainpower. 

Unlike most species which are solitary and reclusive, this one is surprisingly sociable. Scheel’s Down Under research partner Peter Godfrey-Smith discovered that some of its members live in a community in Jarvis Bay near Sydney, which he dubbed Octopolis. If riled up, these dour creatures throw debris at their neighbors, an ability only shared by humans and a few mammals and birds.

When sharks began congregating at the site, instead of backing off, Scheel “turned the problem into a success,” by refocusing their research, according to Godfrey-Smith. “He’s a wonderful person to collaborate with. So thoughtful and also genuinely intrepid,” says the Australian.

Scheel has also studied an octopus in a surprising place —his home. For the 2019 PBS/BBC documentary Making Contact, he lived with a day octopus (Octopus cyanea) named Heidi. The species gets its name because it's active during daylight hours, making it a more ideal house guest. (His daughter Laurel, then 16, named her Heidi because at first the octopus liked to hide a lot.) “She was a fun companion,” says Scheel. “I said ‘hello’ and ‘goodbye’ to her.”

After the filmmakers installed an aquarium in his living room, Laurel often held ‘hands’ with Heidi for as long as 30 minutes. Since octopuses feel and taste with their suckers, Scheel wonders if Heidi knew Laurel was female by detecting traces of estrogen on her skin? He fed Heidi crabs, gave her empty pill bottles to bat around, and the trio did typical American things like watch TV together. When the set was on, Heidi usually moved to the corner nearest Scheel, the one that had the best view of the screen.

As Scheel observed Heidi, Heidi observed him. “You look at an octopus, and you feel like they’re looking back. That’s not an illusion. They are looking back,” he says in the documentary. “When you have an animal that attentive to another animal’s eyes, that is very suggestive of a high level of awareness of the world.”

As an ecologist, Scheel believes all creatures have the same basic needs. He is more intrigued by the similarities between people and octopuses than by their differences. One day he observed a motionless Heidi clinging to the side of the tank, her color patterns flashing in successive waves. The event led him to speculate that she might have been dreaming, a notion that led some scientists to scoff.

“If you approach this from the perspective of universal ecological needs, particularly the idea that all animals’ neural systems are related, then the question becomes ‘Can we examine or test that idea?’” Scheel asks. He followed up with a paper on the subject. “It shouldn’t be awkward for us to frame the question of whether animals dream and bring evidence to bear on it to the extent possible.”

Scheel says the discord in today’s society troubles him, especially the resentment some have for other points of view. In at least in one respect Scheel wishes people were more like octopuses. “They have a brain that is the center of control, but a lot of individual control to investigate things is in the arms locally. One could imagine the distributed centers of control doubting each other. Instead the octopus acts as a very functional, whole integrated organism. I think we may be better off when we can trust each other to respond genuinely,” he says.

George Spencer is a North Carolina-based writer and the former executive editor of the Dartmouth Alumni Magazine.