Sex Recognition and Mate Choice by Male Bufo gargarizans in Central China

Department of Biology, College of Life Science, Xinyang Normal University, SD 464000, China.
ZOOLOGICAL SCIENCE (Impact Factor: 0.86). 06/2012; 29(6):347-50. DOI: 10.2108/zsj.29.347
Source: PubMed


Mate choice is important for successful reproduction, and consequently species have evolved various ways to choose potential high-quality mates. Anuran mate choice and underlying processes have been the subject of several recent investigations, however we are far from a complete understanding of mate choice in this system. In the present study, when given a simultaneous choice between a male and a female of identical size, males did not discriminate between the sexes, and attempted to clasp a male or a female with equal frequency. Test males only released the stimulus toad when a release call was emitted by the stimulus male. When two males with distinct size differences were provided with a male, the male chose the larger one. Moreover, males discriminated between gravid females that differed in body size, choosing larger gravid females over smaller ones. These results suggest that male Bufo gargarizans can discriminate between the sexes, probably based on male release calls, and prefer to mate with larger individual using visual cues.

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    • "But what is the function of this behavior? In some species of explosive breeders where there is intense short-term competition for mates, male-male clasping has been observed due to a lack of sex discrimination during mate search [11], [14], [15]. However, male-male clasps are not typically sustained in these instances, as the production of a release call by the claspee can effectively signal and terminate an inappropriate clasp, minimizing the cost of indiscriminate clasping [11], [14], [15]. "
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