ANDRZEJ KRAUZE
In the wild, male animals typically compete with each other for the attention of the opposite sex. When the female of a species—mouse, rat, cat, dog, or human—puts the lion’s (or rather, lioness’s) share of effort into raising offspring, she becomes a shrewd investor who must be choosy about her mate. Evolutionary biologist Jane Hurst at the University of Liverpool has found that male mice have evolved a cunning trick to distinguish themselves within the dating pool: they produce a specific protein that drives female attraction to male scent, and this molecule, called darcin, helps females remember a specific male’s odor.
Hurst studies how animals use scent cues to recognize different individuals and how they choose among potential mates in the wild. Scientists know more about scent cues in mice than in any other species of mammal. But laboratory mice, being confined to cages in controlled environments, don’t go looking for mates. As Hurst observed wild mice, it became obvious to her that she was missing something. She could see the mice sniffing their surroundings and each other, and she yearned to understand more about the information they were gathering.
Male mice mark virtually every surface in their territory with urine. Because the scent chemicals in urine are volatile, and are specific to each individual, mice have to keep refreshing the marks—and they’ll also cover up ...
