A groundbreaking study published in the journal Cell (2025) has revealed that octopuses can “taste” using the sensors on their sucker cups. This fascinating discovery highlights how octopuses identify spoiled food and non-viable eggs by detecting harmful chemicals produced by microbes.
Scientists from Harvard University and University of California, San Diego studied the California two-spot octopus (Octopus bimaculoides) to understand how these intelligent marine animals use touch to evaluate their surroundings.
Octopus Suckers Do More Than Grip – They Taste Chemicals
Previous research had already shown that octopus arms are highly sensitive. For example, octopuses are known to reach beneath rocks to find prey they can’t see and even inspect their eggs by touch. However, until now, the exact mechanism of this tactile sensitivity remained unclear.
In this latest study, researchers observed female octopuses examining and discarding non-viable eggs. They discovered that bad eggs were covered with bacteria, including bacillus, coccus, and spirillum types—visible under a scanning electron microscope.
Detecting Spoiled Eggs and Rotting Prey with Chemical Sensors
To explore this behavior further, the scientists identified around 300 microbial strains that appeared more frequently on spoiled octopus eggs than on healthy ones. They isolated chemicals produced by these microbes and tested them on engineered octopus sensor cells in petri dishes.
The results were clear: the octopus sensors reacted strongly to the chemical cues associated with spoiled eggs and decaying prey—such as crabs that had begun to rot. This suggests that octopus sucker cups are equipped with chemoreceptors that help them detect microbial byproducts and make feeding or egg-care decisions accordingly.
Evolutionary Advantage: Chemotactile Sensation Helps Survival
This chemotactile sense—a combination of touch and taste—gives octopuses a powerful evolutionary advantage. It allows them to:
- Avoid rotten or toxic food sources
- Maintain the health of their offspring by removing dead or infected eggs
- Navigate and interact with their environment more effectively
Such advanced sensory abilities highlight the intelligence and complexity of cephalopods, further establishing them as some of the most fascinating creatures in the ocean.
Study Reference and DOI
This research was led by Rebecka J. Sepela et al. and is titled “Environmental microbiomes drive chemotactile sensation in octopus”. It was published in Cell (2025).
DOI: 10.1016/j.cell.2025.05.033