Humans aren't the only mammals with a swinging singles scene. Nine other species engage in a process known as lekking, whereby bachelor males congregate in certain areas during the mating season looking for love. And according to a report published today in the Proceedings of National Academy of Sciences, females may be more aggressive about landing eligible males than previously thought.

Earlier work had shown that in bird species that engage in lekking, females often compete for preferred males. For mammals that form leks, however, scientists thought that factors other than mate choice attracted females to the party. Now the new study, conducted by Jacob Bro-Jrgensen of the Zoological Society of London, reveals that in the case of topi antelopes, leks actually have poorer food supplies, higher rates of predation and higher levels of harassment for females than surrounding areas do. But the opportunity to mate with desirable males, it seems, offsets these drawbacks. After two years of studying topi populations on the Serengeti and Masai Mara plains, Bro-Jrgenson reports that he witnessed competitive aggression between females (see image) over so-called central males, which tend to be larger and older and to have darker facemasks than their peers. In fact, some females even went so far as to disrupt matings that were already in progress. Bro-Jrgenson concludes that "the finding suggests that the forces leading to lek evolution in mammals and birds may be more similar than previously acknowledged."