Nonvisual mate choice in the Pyrenean mountain newt (Euproctus asper): females prefer small males

In many species, females prefer large males as mates. In this paper, we examined whether female Pyrenean mountain newts (Euproctus asper) would show a preference for large males in a simultaneous choice situation. When we tested for a visual preference relative to male body size using visual cues, females did not prefer large males. When chemical cues were presented, females did show a preference, but contrary to our prediction, they preferred the smaller of two males. E. asper males exhibit coercive mating behavior (amplexus), keeping females from feeding for several hours or even days, which may explain why females avoid large, physically stronger, and thus, more coercive males. The predominantly nocturnal lifestyle may explain why visual cues are less important for mate discrimination in this species.