Octopuses use touch to “read” seafloor microbes, revealing new way marine animals navigate their world

Scientists have discovered that octopuses possess a remarkable ability to detect and respond to microbial communities on the seafloor through touch alone, offering new insights into how marine animals interact with their microscopic environment. This groundbreaking research, published in the journal Cell, reveals that the California two-spot octopus can sense chemical signals from microbiomes using specialized receptors lining their eight arms.

Unlike humans, who can only detect microbial activity through smell—like recognizing spoiled food—octopuses literally feel their way through a world of invisible microorganisms. Their arms, which contain more neurons than their central brain, are equipped with chemotactile receptors that allow them to reflexively respond to specific chemical signatures from different microbial populations as they explore the ocean floor.

Led by Harvard University postdoctoral fellow Rebecka Sepela, the research team chose octopuses as their study subjects because these cephalopods are natural explorers that rely heavily on touch to navigate their environment. The discovery highlights a previously unknown sensory capability that may help octopuses identify safe areas, locate food sources, or avoid potentially harmful microbial communities.

This research opens new doors for understanding how marine animals adapt to their microbial surroundings. While scientists have long known that microbes influence animal development, disease, and digestion from within, this study demonstrates how environmental microbiomes can actively shape external animal behavior. The findings may have broader implications for understanding marine ecosystem interactions and could inform conservation efforts as ocean environments continue to change due to climate impacts.