Female guppies Poecilia reticulata prefer males that can learn fast.

The role of learning ability as a potentially desirable male trait in sexual selection was investigated in the guppy Poecilia reticulata. Mate preference tests and the rate at which a male learnt two mazes were used to determine whether female preference was related to male learning ability. In addition, male body size and saturation of the orange patches were measured. Female preference was found to be related to rate of learning, such that males that learnt the mazes faster were found to be more attractive to females, but was not found to be related to body size or saturation.