The Influence of Male and Female Body Size on Copulation Duration and Fecundity in Drosophila Melanogaster

Abstract

Lefranc, A. and Bundgaard, J. 2000. The influence on male and female body size on copulation duration and fecundity in Drosophila me1anogaster.-Hereditas 132: 243-247. Lund, Sweden. ISSN 0018-0661.We studied two components of the mating system, copulation duration and early fecundity, in relation to body size in Drosophila melanogaster. Body size variation was created experimentally by varying the degree of crowding (starvation) among larvae from an inbred strain, keeping the genetics and temperature as constant as possible. Hence, in contrast to most previous studies, where genetic and environmental variation have been confounded, we aimed at investigating how much pure phenotypic variation could influence copulation duration and early fecundity. It is shown that copulation duration and fecundity both strongly dependent on female body size, but either not or much less so on male body size. Small females mate faster than medium or large females and small females have the lowest fecundity. Among males, medium-size males are more fecund than smaller or larger males, resulting in stabilising selection for intermediate male size. These results are in contrast with previous findings. A g n k Lefranc, Universlte Pierre et Marie Curie, Laboratoire Fonctionnement et Evolution des Systemis Ecologiques, case 237 -Bat. A , 7 eme et. piece 729, 7, quai St-Bernard 75252 Paris Cedex 05,

The affect of female body width on copulation duration in Centrobolus inscriptus (Attems)

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The consequences of genetic variation in sex peptide expression levels for egg laying and retention in females

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