Octopuses are cephalopods that live in oceans around the world. They are also some of the most intelligent creatures on Earth. Their brain structures vary depending on where they live. For example, “octopuses living in deep waters with limited interactions with other animals have brains similar to rodents,” while “reef octopuses have much larger brains with some properties similar to primates, which the octopi need for complex visual tasks and social interactions,” said Live Science.
Some scientists claim that octopuses could be the next big species after humans go extinct and that there is much to learn about the tentacled sea creatures. These are some ways that octopuses have displayed their intelligence.
Camouflage capabilities
Octopuses have an “incredible ability not just to change the color and patterns on their skin but also to transform their body’s shape and texture,” said National Geographic. They use this ability to trick and confuse predators and prey. The animals “impersonate all sorts of animals that are more threatening or venomous than they are,” as well as change appearance to “appear less threatening and get close to their prey.”
Color-changing could be used to communicate with each other as well as attract mates. “We argue that perhaps that is actually a physical manifestation of an internal state,” Tessa Montague, a neuroscientist at Columbia University, said to National Geographic. “They have this incredible electric skin that is basically showing you what they’re thinking.”
Body-wide intelligence
“The central brain of an octopus contains 10% of their neurons, their optic lobes have 30% and the remaining 60% of the neurons are found in their tentacles,” said Oceana Canada. This allows the sea creatures to have intelligent arms. The arms of the octopus essentially have “mini-brains” and can each act independently. The tentacles are “able to taste, touch and move without direction — the centralized brain is also able to exert top-down control,” said the National History Museum in the U.K.
Their brain also has the ability to store and apply long-term memory. “Their long-term memory shows that they store the information they have obtained through trial-and-error learning,” Oceana Canada. They are also able to recognize specific humans. In one study, an “octopus came to dislike a researcher that was working with it” and would “squirt water out of its tank at them” each time they walked by.
Problem-solving masters
“An octopus’ brain-to-body ratio is the largest of any invertebrate. It’s also larger than many vertebrates, although not mammals.” said the National History Museum. “They’ve solved mazes and completed tricky tasks to get food rewards,” said Jon Ablett, a senior curator of mollusks at the museum. “They’re also adept at getting themselves in and out of containers.”
Octopuses have shown the ability to use tools and have been seen piling up rocks, shells, bottle caps and glass. One species, the common blanket octopus, carries tentacles from the Portuguese man o’ war (another species) as a weapon. “These tentacles carry a potent and painful venom — the common blanket octopus is immune but can inflict their effects on unwitting predators and prey.”
Potential sentience
Scientists have been curious about the inner lives of octopuses because of their displayed intelligence. A 2022 study found that the genes of two octopus species shared a genetic quirk present in humans as well. “When you’re dealing with an octopus who’s being attentively curious about something, it is very hard to imagine that there’s nothing experienced by it,” Peter Godfrey-Smith, a professor of history and philosophy of science at the University of Sydney and the author of “Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness,” said to the BBC. “It seems kind of irresistible. That itself is not evidence, that’s just an impression.”
Octopus sentience is being called into question as octopus farming has become controversial. Many view octopus aquaculture as inhumane because of the cephalopod’s intelligence. In 2024, Washington and California became the first states to pass bans with similar legislation being introduced in New Jersey, Hawaii and Oregon.