5 - Reproductive strategies of the crickets (Orthoptera: Gryllidae)

Summary

ABSTRACT

Cricket reproduction has been studied at both the proximate level, focussing on the neurophysiological mechanisms involved in the transmission and reception of calling song, and the ultimate level, focussing on how selection might have acted on male and female behavior. Although mating patterns are diverse, most crickets do not have sub – stantial male contributions to females or offspring, making female choice a common mode of sexual selection. Males are extremely aggressive, with possession of a burrow and large body size tending to increase the likelihood of success in male interactions. Population density is an important determinant of male spacing, calling, and mating success.

Although several studies have established the existence of non–random mating, the song attributes that females presumably use in making long–distance discriminations are not always clear. Diel patterning of calling is likewise little studied. Non–callers may represent, not a distinct class of males pursuing an alternative mating strategy, but males responding opportunistically to changes in population density. Several cricket species appear to have responded to selection pressure by phonotactic parasitoids.

Female crickets commonly mate more than once; females benefit in several ways from having larger sperm reserves. Field studies comparing traits of males found paired with females with those of calling males show a consistent relationship between pairing success and male age. Age seems to be used as an indirect indication of male quality. Courtship behavior may also indicate variation in male quality to females.