A ‘Self-Aware’ Fish Raises Doubts About a Cognitive Test | Quanta Magazine

A little blue-and-black fish swims up to a mirror. It maneuvers its body vertically to reflect its belly, along with a brown mark that researchers have placed on its throat. The fish then pivots and dives to strike its throat against the sandy bottom of its tank with a glancing blow.

A ‘Self-Aware’ Fish Raises Doubts About a Cognitive Test | Quanta Magazine