They're no good at poetry. They don't buy flowers. But scientists are reporting that male mice have their own special way of impressing the ladies:
They sing.
Scientists already knew that male mice send out high-pitched mating calls, inaudible to the human ear. But the vocalizations had been seen as mere squeaks. For a new study published in Journal of Ethology, researchers at the University of Veterinary Medicine, Austria's Konrad Lorenz Institute of Ethology analyzed slowed-down recordings of male mice's vocalizations and found that the squeaks were actually sophisticated and complex. It's a bit like birdsong.
A separate study published in Physiology & Behavior showed that each male mouse has his own signature tune, much like a fingerprint. A female within earshot listens to the song and decides whether she's interested, taking care not to hook up with one of her brothers. The researchers say a female mouse can tell one of her siblings from other suitors even if she's never heard him sing before.
What sort of song really gets a female mouse hot and bothered? For clues, scientists looked to "sexy syllable" research on birds.
Studies have shown that females of some bird species really groove on guys who belt out complex songs. Does the rule apply to mice too? The researches aren't sure. But it's clear that lab mice lack the singing chops of wild "house" mice, which are better at producing songs with the complex, high-frequency notes that drive the ladies wild.
"It seems as though house mice might provide a new model organism for the study of song in animals," study co-author Dr. Dustin Penn, a biologist at the university, said in a written statement. "Who would have thought that?"