Showing papers by "Leo W. Beukeboom published in 2005"
TL;DR: The results indicate that although males show a decay of sexual function, they are still able to fertilize uninfected females and the absence of genomic incompatibilities suggests that these effects are due to the difference in mode of reproduction.
Abstract: Females infected with parthenogenesis-inducing Wolbachia bacteria can be cured from their infection by antibiotic treatment, resulting in male production. In most cases, however, these males are either sexually not fully functional, or infected females have lost the ability to reproduce sexually. We studied the decay of sexual function in males and females of the parasitoid Leptopilina clavipes. In western Europe, infected and uninfected populations occur allopatrically, allowing for an investigation of both male and female sexual function. This was made by comparing females and males induced from different parthenogenetic populations with those from naturally occurring uninfected populations. Our results indicate that although males show a decay of sexual function, they are still able to fertilize uninfected females. Infected females, however, do not fertilize their eggs after mating with males from uninfected populations. The absence of genomic incompatibilities suggests that these effects are due to the difference in mode of reproduction.
54 citations
01 Jan 2005
TL;DR: A number of fitness components of arrhenotokous and thelytokous Venturia canescens were measured, finding that thelyTokous females had higher egg loads and ovariole numbers and laid more eggs per host larva.
Abstract: Theory predicts that asexual reproduction has a competitive advantage over sexual reproduction because of the cost of producing males. One counterbalancing force may be reduced phenotypic fitness of asexuals as a consequence of mutation accumulation. We measured a number of fitness components of arrhenotokous and thelytokous Venturia canescens. Thelytokous females had higher egg loads and ovariole numbers and laid more eggs per host larva. Arrhenotokous females had a higher longevity. These differences are considered in the context of different life histories of both reproductive modes.
7 citations
01 Jan 2005
TL;DR: This work shows that superparasitizing N. vitripennis females do not adjust their progeny sex ratio as a function of the sex of eggs laid by the preceding female, and investigates whether this was due to ovicide or crowding.
Abstract: Nasonia wasps conform to many qualitative and sometimes even quantitative predictions of simple sex allocation models. They are now being used to test more elaborate sex allocation models. In contrast to theoretical predictions, we show that superparasitizing N. vitripennis females do not adjust their progeny sex ratio as a function of the sex of eggs laid by the preceding female. The number of offspring of superparasitized females was smaller than that of single females, but we could not determine whether this was due to ovicide or crowding.
2 citations
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01 Jan 2005
TL;DR: Most organisms reproduce sexually, but the evolution of sexual reproduction is not yet well understood and deviations are known to occur by driving sex chromosomes and other sex ratio distorters.
Abstract: Most organisms reproduce sexually, but the evolution of sexual reproduction is not yet well understood. Sexual reproduction leads to new variation and adaptations to the environment, but sex is also costly. Some insects reproduce without sex through parthenogenesis or paedogenesis. Almost all sexual insects have two separate sexes, male and female. There are many mechanisms of sex determination. Most insects have male heterogamety (males XY, females XX). Female heterogamety and haplodiploidy (males haploid, females diploid) are less abundant. Proportions males and females in populations are typically equal, but deviations are known to occur by driving sex chromosomes and other sex ratio distorters.