Female choice and the consistency of courtship feeding in black-horned tree crickets Oecanthus nigricornis walker (Orthoptera : Gryllidae : Oecanthinae)

Citation
Wd. Brown et Mm. Kuns, Female choice and the consistency of courtship feeding in black-horned tree crickets Oecanthus nigricornis walker (Orthoptera : Gryllidae : Oecanthinae), ETHOLOGY, 106(6), 2000, pp. 543-557
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ETHOLOGY
ISSN journal
0179-1613 → ACNP
Volume
106
Issue
6
Year of publication
2000
Pages
543 - 557
Database
ISI
SICI code
0179-1613(200006)106:6<543:FCATCO>2.0.ZU;2-Q
Abstract
Courtship feeding in insects is often strongly correlated with insemination duration and therefore provides a potential postcopulatory episode of sexu al selection. We tested whether courtship feeding and other courtship trait s in the black-horned tree cricket Oecanthus nigricornis showed sufficient consistency potentially to respond to sexual selection by testing whether t hey differed significantly among males. Duration of courtship feeding diffe red among males when measured repeatedly and this caused significant differ ences in the duration of spermatophore attachment, a trait that determines the maximum duration of insemination and thus has important fitness consequ ences in crickets. We also partitioned variance in courtship behaviour betw een the sexes to test whether differences in courtship behaviour were attri butable primarily to males, females or both sexes. Duration of spermatophor e attachment was controlled by females and therefore represents a mechanism of female mate choice. Significant variation in duration of spermatophore attachment was associated with differences between individuals of both sexe s. Differences among males indicate that females agree in their preference of certain males whereas differences among females indicate that females di ffer in their receptivity to postcopulatory courtship and insemination. The fact that differences among males in duration of spermatophore attachment were due to significant differences solely in the period of courtship feedi ng indicates that postcopulatory female choice was mediated through courtsh ip feeding. Whether males manipulate female choices by allocating more or f ewer resources requires further testing, but we found that males court some females more vigorously than others after females dismount. The number of previous mates had opposite effects on the duration of courtship feeding fo r the sexes, decreasing it for males but increasing it far females, and we discuss the possible causes of these results.