Scientist claims if humans go extinct, Octopuses could be the next builders of civilization

Earth has seen its fair share of extinctions. Fossil records show that the planet has experienced five major mass extinctions, with the last one occurring about 65 million years ago, wiping out the dinosaurs. Now, scientists suspect we might be witnessing another extinction event. Our impact on biodiversity—through habitat destruction and the detrimental effects of climate change—has already caused irreversible damage, warns a 2023 study in PNAS. According to a 2022 paper in Nature, if humans don’t curb greenhouse gas emissions and deforestation, we could lose up to 50% of species by 2080.

More immediate threats like nuclear war or another massive asteroid impact could speed up this extinction, possibly wiping out humans and apes even sooner. This raises a thought-provoking question: if we were to disappear, what species would rise in our place?

Enter the octopus. Biologist Tim Coulson, a professor of ecology and evolution at the University of Oxford, suggests that these mysterious sea creatures might just be the successors to humanity. “There are very many species of octopus, not one species [like] humans…and they live in a wide variety of habitats including deep ocean habitats as well as coastal habitats,” Coulson explains. “Although some populations and some species may fare badly, I think there’s an opportunity for others to survive, radiate, [and] to diverge over evolutionary time to colonize a wide variety of habitats, including coastal habitats.” “Plus, it would help the octopus cause if humans stopped hunting and eating them,” Coulson adds.

The idea of octopuses taking over sounds far-fetched, but Coulson reminds us that nature has often shown how one species can capitalize on another’s extinction. After the dinosaurs vanished, mammals evolved to dominate. “One can imagine any number of scenarios where in some apocalyptic post-human world other species currently quietly leading their lives come to be the dominant ones on the planet, like our little mammalian ancestors paved the way for us humans after the fall of the dinosaurs,” says Andrew Whiten, Ph.D., a professor at the University of St. Andrews.

Octopuses already have traits that could make them formidable contenders. Some species have been observed using tools—such as coconut shells for armor and shelter—and solving complex mazes in labs. Coulson mentions that octopuses in captivity have been known to escape their tanks, visiting other octopuses in nearby enclosures.

This intelligence might be unlike human intelligence, notes Andy Dobson, Ph.D., an ecology professor at Princeton University. “Octopus seem to have highly evolved nervous systems, although I’m not sure we’d call the dense concentration of neurons that connect their eight limbs and huge eyes a brain, [it’s] more a massive data processing center,” Dobson says. “Their intelligence derives from having multiple limbs and two huge eyes to sense their environment.”

Though octopuses aren’t the only creatures showing remarkable smarts, Coulson points out their dexterity as a key advantage. “They’re highly dextrous [and] able to use their eight limbs to manipulate all sorts of objects,” he says. “And although crows and various birds are able to bend bits of wire in their beaks or drop stones into water to raise water levels and reach food, they haven’t got the dexterity that octopuses appear to.”

Unlike humans, octopuses lack vertebrae, so their civilizations would likely thrive in the ocean rather than on land. For octopus communities to evolve, Coulson proposes they would need access to a reliable energy source—perhaps tidal power for coastal octopuses or hydrothermal vents for deep-sea ones, though the latter would be more challenging.

But their biggest hurdle might be their social behavior. Octopuses are generally solitary, sometimes even cannibalistic, and this could prevent the formation of octopus civilizations, says Peter Godfrey-Smith, Ph.D., a professor at the University of Sydney. “Octopuses are not well set up to build a human-like society because of their social habits—the fact that they are not likely to develop a culture,” Godfrey-Smith says. “When I talk about ‘culture’, I mean the ability to learn from others in your society… for octopuses, the first move they’d have to make is to become more social, and also bring up their young differently.”

Godfrey-Smith explains that octopuses inherit very little culture—at least, as we humans experience it—from their parents at birth as both are nearly non-existence in their upbringing. To develop a closer knit society, octopuses may need to develop more intergenerational connections, he says.

As these kinds of social changes have not yet evolved in octopuses’ last 50 to 100 million years of existence, it’s unlikely that this will change anytime soon, Dobson says. But in their defense, scientists have observed in the last decade that some octopus species may be more social than others, with some octopuses living in groups of ten or more.

There’s also the unfortunate fact that human activities have likely already limited octopuses’ potential for evolution. Pollution, overfishing, and climate change have already taken a toll on these creatures, and the damage may be greater than we realize, says Dobson.

If octopuses aren’t the ones to rise after us, Dobson suggests that nematodes could be the surprising survivors of Earth’s sixth mass extinction. Meanwhile, Godfrey-Smith places his bet on cockatoos as the likely heirs to our throne.