Paternity control for externally fertilised eggs: behavioural mechanisms in the waterfrog species complex |
| |
Authors: | Thierry Lengagne Pierre Joly |
| |
Institution: | 1. UMR–CNRS 5023 Ecologie des Hydrosystèmes Fluviaux, Université de Lyon, Université Lyon 1; Bat. Darwin C, 69622, Villeurbanne Cedex, France
|
| |
Abstract: | Male competition for mates and female mate choice are key mechanisms involved in sexual selection. Surprisingly, these mechanisms
have often been investigated separately although they appear to interact in many species. Male–male competition for territories
located at the best places or to establish dominance relationships often explain mating patterns. Such male behaviours may
affect and sometimes even hinder female mate choice, as in the case of sexual coercion. While in many species females are
able to exert cryptic control over paternity (i.e. a process allowing females to bias offspring production toward certain
males after intromission), in other species external fertilisation prevents females from doing so. This is the case in the
waterfrog hybridisation complex where the hybrid Pelophylax esculentus can only produce viable offspring by pairing with the parental species Pelophylax lessonae (hybridogenetic reproduction). We examined two potential processes that could enhance such mating combinations. Firstly,
by monitoring male spatial distribution within six choruses, we showed that the proportion of P. lessonae males located at the edge (in the best position to grasp females arriving at the chorus) cannot explain the frequency of
mating combinations observed. Secondly, an experimental approach emphasised a new way for anuran females to favour paternity
of a particular male in a sexual coercion context. When females are forcefully paired with an incompatible male, they cannot
remove the male grasped on their back by themselves. Nevertheless, by controlling the movement of the pair within the chorus,
these females often change mates by enhancing male competition instead of laying eggs. In many species with externally fertilised
eggs, it may be thus necessary to take into account this new possibility for females to control offspring paternity. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|