Octopuses use specialised sensory cells in their suckers to chemically sample surfaces, allowing them to "taste" by touch as they explore and handle prey
Sensory capability in the arms
Research has identified specialised chemosensory cells embedded in octopus suckers that detect chemical cues on contact, enabling the animal to evaluate food and the environment by touch rather than solely by mouth.
How touching becomes tasting
Each sucker contains numerous receptor cells that respond to dissolved molecules and defensive chemicals from potential prey, so an arm exploring a crevice can effectively "pre‑taste" items before the octopus decides to eat them.
Independent arm function
Octopus arms are highly autonomous, with neural circuits in the peripheral nervous system that allow individual limbs to process sensory information and perform complex grasping and investigative behaviours with minimal direct control from the central brain.
Ecological and behavioural benefits
This chemotactile sense helps octopuses locate and identify buried or hidden prey such as crustaceans and mollusks in low‑light or complex benthic habitats, improving foraging efficiency and reducing risky handling of toxic or unpalatable items.
Comparative perspective and ongoing research
Similar tactile‑chemosensory adaptations appear in other cephalopods, and ongoing studies are revealing molecular and cellular specialisations that underpin this unique sense, offering insight into how distributed nervous systems support sophisticated behaviour in invertebrates.
Takeaway
By tasting with their arms, octopuses combine touch and chemical detection to explore, forage and judge food items directly at the point of contact, a powerful adaptation that complements their intelligence and makes them exceptionally skilled hunters in complex marine environments.