The sense of smell in adult female rats is more acute than that in rat pups.

The amount of scent produced by rat pups increases when they are in the presence of a female rat that did not bear them.

Female rats that have given birth are more affected by olfactory cues than are female rats that have never given birth.

A female rat that has given birth shows maternal behavior toward rat pups that she did not bear more quickly than does a female rat that has never given birth.

The development of a female rat's maternal interest in a rat pup that she did not bear is inhibited by the odor of the pup.