Chromatics and Cognition: The Intriguing World of the California Two-Spot Octopus
A highly intelligent and enigmatic creature that has become a groundbreaking discovery for geneticists.
I have a very deep passion for octopuses. I have done several short documentaries about them and have traveled twice to Indonesia just to film them in their native habitat. (And yes, as you’ve likely heard before plural of octopus is octopuses not octopi because the root is Latin, not Greek). My home office is filled with octopus imagery and iconography and I made a vow many years ago nefer to eat octopus. (Squid are fine in my playbook, as well as other mollusks. If you want to debate this, fine.)
The California two-spot octopus, Octopus bimaculoides, has become one of the key species helping scientists understand the strange biology behind octopus intelligence.
Often found hiding in small rocky nooks of the Pacific coastline from Central California to Baja, these octopuses have garnered attention for their distinctive blue "eye-spots," which are not true eyes but rather mimicry patterns that confuse predators and prey. These spots are part of their astonishing color-changing abilities. Octopus use specialized skin cells known as chromatophores, which expand and contract to change the color and pattern of their skin, an ability they use for camouflage, communication, and courtship.
Their behavior is remarkably complex. They are mostly solitary creatures, reclusive, with the exception of mating. Research has shown that they have a fascinating ability to learn and navigate mazes, unscrew jars, and engage in play, indicating a level of intelligence that is unusual for an invertebrate.
The study of octopus intelligence has implications for our understanding of intelligence as a biological phenomenon. Octopuses diverged from the lineage that would lead to humans around 600 million years ago, and they share a common ancestor with us going far back that was likely a simple, multicellular organism, supposedly some kind of primitive flatworm. This evolutionary gulf means that octopus intelligence developed along a trajectory entirely distinct from our own. Their nervous system is decentralized. Much of it sits in the arms, which can act on their own and respond to the world independently. It suggests intelligence can emerge from very different kinds of neural systems.
If you haven't seen it yet, I highly recommend YouTuber Mark Rober's recent video on octopus intelligence. His pet octopus Sashimi is a California Two Spot Octopus.
Octopuses can change the color and texture of their skin in an instant, blending into rocks and kelp or flashing patterns that may signal to other animals. This remarkable ability is controlled not only by the brain but by networks of nerve cells spread throughout the body. The result is a kind of distributed intelligence, where perception and action are shared across the body rather than directed from a single command center. Research on octopuses is forcing scientists to rethink what intelligence looks like in the animal world. Instead of a single ladder with humans at the top, it may be better understood as a spectrum of abilities that evolve in different ways across different species.
It gets crazier. Recent discoveries have shown the animal's remarkable ability to actually see with its skin. A University of California at Santa Barbara study found that the skin of the California two-spot octopus can sense light even without input from the central nervous system. The animal does so by using the same family of light-sensitive proteins called opsins that are found in other seeing organisms, even humans. The researchers’ findings appeared in the Journal of Experimental Biology.
The octopus also reminds us that intelligence did not evolve just once. Octopuses and humans last shared a common ancestor more than 500 million years ago, that worm. Their intelligence developed along a completely separate path. And it arose under very different conditions. Octopuses live short lives, rarely interact with other octopuses, and lack the social structures that many scientists believe helped drive intelligence in mammals and birds. Yet they still show remarkable learning ability and problem solving. The lesson is that intelligence is not a single ladder leading upward. It can emerge in different forms across the tree of life, shaped by the particular challenges an organism faces in its environment.
New studies, particularly in the field of genomics using the genome of the California Two Spot octopus, have unveiled the fascinating diversity of the octopus's genetic blueprint. Their genome is large and contains a greater number of genes than that of a human, with a large proliferation of gene families associated with neural development, hinting at biological underpinnings of their brainpower and behavior. These genetic insights could explain not only their sophisticated nervous systems but also their adaptability and the evolution of their unique traits. Life finds a way. Sometimes several ways.
For Californians interested in science and the ocean, the two-spot octopus is more than just another marine animal along the coast. It has become one of the species helping scientists understand how intelligence can evolve in entirely different ways. The deeper researchers dig into its genome and nervous system, the more surprises they find. What began as the study of a local octopus has turned into something much larger, raising new questions about how minds can emerge in the living world.