A new sexual selection pattern in a frog (Odorrana tormota) with ultrasonic communication

The current study has revealed a unique sexual selection pattern in Odorrana tormota, a species renowned for its ultrasonic communication, which differs from the patterns observed in other anuran taxa. Typically, females listen to male vocalizations and exhibit phonotaxis towards preferred traits for mate selection. In contrast, female O. tormota do not actively approach displaying males for mate selection; instead, they use courtship calls to attract potential mates and incite male competition for access to them. Considering that successful male O. tormota in securing a mating opportunity are always those who embrace the female first, and the majority of them (84%) exhibit faster response times to female calls. We propose that female O. tormota can increase their likelihood of mating with high-quality males (as indicated by heightened responsiveness) by using courtship calls to attract males, while minimizing potential costs associated with active mate selection. Additionally, the differences in ultrasound perception between male and female O. tormota can be attributed to their divergent selection pressures, as male frogs must accurately perceive and locate the female's call in challenging environments to increase their mating opportunities, whereas females do not face similar pressure.