Being the comparative psychologist he was, he conducted what is believed to be the "first experimental study of learning by snakes".

The aggression of this fish has been studied by ethologists and comparative psychologists.

Paralleling these studies, comparative psychologists provided tools or apparatuses that could be handled in different ways.

The second, primatologists and comparative psychologists have found imperative evidence that suggest true learning through imitation in animals.

A handful of comparative psychologists at American universities have attempted to demonstrate economic reasoning in non-human animals.

People who have made notable contributions to ethology (many listed here are actually comparative psychologists):

But when Nicola Clayton, a comparative psychologist, first heard about the claim, she had a different reaction.

A persistent question with which comparative psychologists have been faced is the relative intelligence of different species of animal.

A wide variety of species have been studied by comparative psychologists.

Many of these were active in fields other than animal psychology; this is characteristic of comparative psychologists.