Social situation, sperm competition and sex allocation in a simultaneous hermaphrodite parasite, the cestode Schistocephalus solidus
Details
Serval ID
serval:BIB_CAA7B27B065F
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Social situation, sperm competition and sex allocation in a simultaneous hermaphrodite parasite, the cestode Schistocephalus solidus
Journal
Journal of Evolutionary Biology
ISSN
1010-061X
Publication state
Published
Issued date
2001
Peer-reviewed
Oui
Volume
14
Number
6
Pages
942-953
Language
english
Abstract
Evolutionary theory predicts an influence of mating group size on sex allocation in simultaneous hermaphrodites, We experimentally manipulated the social situation during reproduction in a simultaneous hermaphrodite parasite, the tapeworm Schistocephalus solidus, by placing worms as singles, pairs or triplets into an in vitro system that replaces the final host. We then determined the reproductive allocation patterns after 24 h (i.e. before the start of egg release) and after 72 h (i.e. around the peak of egg release rate) using stereology. After 24 h, sex allocation strongly depended on worm volume (which is determined in the second intermediate host), but was not significantly affected by the social situation experienced during reproduction. After 72 h, worms in groups had less vesicular sperm (Le, sperm to be used in future inseminations) than singles. They also stored significantly more received sperm in their seminal receptacles than singles, suggesting that more sperm had been transferred in groups. Moreover, worms in triplets stored significantly more received sperm than worms in pairs, suggesting that they either mated more often and/or transferred more sperm per mating. This Suggests a behavioural response to the increased risk of sperm competition in triplets. We further discuss the relative importance of sex allocation decisions at different life-history stages.
Keywords
cestode, histology, local mate competition, mating group size, parasite, sex allocation, simultaneous hermaphrodite, size-dependent sex allocation, sperm competition, stereology
Web of science
Open Access
Yes
Create date
25/01/2008 11:43
Last modification date
20/08/2019 16:45