In the beetle Diaprepes abbreviatus (L.) females are larger on average than males, as indicated by elytra length. Size-assortative matings were observed in wild populations in Florida and in laboratory mating experiments. We tested three mechanisms for this size-assortative mating: (1) mate availability; (2) mating constraints; and (3) mate choice. We found that mate choice influenced size-assortative mating by: (1) large and small males preferring to mate with large females; (2) large males successfully competing for large females, leaving small males to mate with small females; and (3) females accepting large males as mates more readily than small males. Males increased their reproductive success by mating with larger, more fecund females. They transferred protein to females during mating.
Bibliographical noteFunding Information:
We thank W. J. Schroeder and H. Smith for supplying laboratory-reared weevils. We also thank V. Chew for advice on statistical analysis and J. Brockmann and Y. Lubin for comments on the manuscript. This research was supported by a postdoctoral Fellowship Award No. If-0183-94 from BARD, The United States-Israel Binational Agricultural Research and Development Fund.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology