Overview
- Dartmouth researchers trained three California two‑spot octopuses to use a mirror to infer the location of a hidden crab image and then move to that location rather than to the mirror itself.
- To rule out smell or touch, the team projected a virtual crab behind the animals and rewarded correct responses with a live crab so behavior relied on visual mirror information.
- The octopuses went to the correct side about 73 percent of the time, sometimes making a full 180‑degree turn, and they became faster at reaching the projected stimulus over repeated trials.
- Authors stress major limits: the experiment used only three individuals, octopuses allowed roughly one large reward trial per day because of motivation and satiety, and short adult lifespans constrained training time and sample size.
- Researchers say the result suggests possible convergent evolution of spatial cognition in an invertebrate and call for follow‑up work with more animals, varied species, and neural measurements to test whether octopuses form internal spatial maps.