Effects of age and repeated mating on male sperm supply and paternity in a parasitoid wasp

Autor: Christophe Bressac, Claude Chevrier, Hong Do Thi Khanh
Přispěvatelé: Institut de recherche sur la biologie de l'insecte UMR7261 (IRBI), Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2009
Předmět:
Zdroj: Entomologia Experimentalis et Applicata
Entomologia Experimentalis et Applicata, Wiley, 2009, pp.207-213. ⟨10.1111/j.1570-7458.2008.00810.x⟩
ISSN: 1570-7458
0013-8703
DOI: 10.1111/j.1570-7458.2008.00810.x
Popis: International audience; Post-copulatory paternity biases after female multiple mating are major constraints on both male and female reproductive systems. The outcome of paternity in certain situations is only controlled directly by male sperm stock. This was tested experimentally in the parasitoid wasp Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae), in which sperm stocks are small (several hundred) and the fertilizing efficiency of stored sperm is high (the ratio of sperm stored/fertilized eggs is about 0.75). Sperm in seminal vesicles and paternity of males of different status (virgin young, virgin old, or young previously mated) were measured after female single and double mating. The amount of sperm in the seminal vesicle differed according to male status (increasing from previously mated males to old males), but there was no difference in sperm stored by females after a single mating. In double mating experiments with two males of different status, paternity increased linearly with the relative amount of sperm in seminal vesicles. Paternity distribution conforms to ‘a fair raffle' of sperm from both donors following complete mixing of sperm prior to fertilization. Thus, in a female multiple mating context, male fitness depends principally on their sperm stock, which in turn depends on life history parameters, such as age and previous mating.
Databáze: OpenAIRE