Calling behavior of males and females of a Bornean frog with male parental care and possible sex-role reversal
Male midwife toads (Alytes cisternasii) responded differently depending on the call frequency and call rate of other males. I tested female Iberian midwife toads with the same set of stimuli used earlier with males. Females responded faster to high call rates, and female vocal activity was greater in response to low-frequency male calls. Thus, in both sexes, the vocal response differs in the same direction according to signal frequency variation, but the magnitude of the response is greater in males than in females. In the light of these results, I discuss the implications for sexual selection of this reciprocal calling.