Crayfish can feel anxious, according to a new study showing that human emotions are more widespread among animals than previously thought.
An experiment has shown that freshwater crayfish can be induced into a
state of deep anxiety only alleviated by the same kind of tranquilisers
used to treat people afflicted by a similar condition. The study
revealed that the crayfish emotion is governed by the same chemical
transmitters in its nervous system that are involved in controlling
anxiety in humans, which is why anxious crayfish respond to
benzodiazepine, a tranquiliser used to treat anxiety in people.