What stops the ‘diploid male vortex’?—A simulation study for species with single locus complementary sex determination

详细信息    查看全文

• 作者：Silke Hein ; Hans-Joachim Poethke ; Silvia Dorn
• 关键词：Bee ; Dispersal ; Diploid male production ; Extinction risk ; Sex determination mechanism ; sl-CSD ; Sex ratio distorter ; Parasitoid ; Pollinators
• 刊名：Ecological Modelling
• 出版年：2009
• 出版时间：17 July 2009
• 年：2009
• 卷：220
• 期：13-14
• 页码：1663-1669
• 全文大小：506 K

文摘

The survival of hymenopteran populations especially that of ecologically and economically important pollinators and parasitoids, has become a major topic for empirical and theoretical studies. Complementary sex determination (CSD) in Hymenoptera may impose a substantial genetic load through the production of inviable or sterile diploid males. Modelling and laboratory studies have indicated that this genetic load may trigger a ‘diploid male vortex’ leading to rapid extinction of populations.

Here we take a broader theoretical approach to analyze why populations exhibiting CSD persist in nature, even if they contain large proportions of homozygous diploid individuals. Using an individual-based model of spatially structured hymenopteran populations, we show that (i) inviability or reduced fertility of homozygous individuals, (ii) female-biased sex ratio, and (iii) strong intra-specific competition can mitigate the negative influence of CSD on population persistence and that (iv) already extremely low dispersal rates will result in long term survival. These findings underline the importance of life history traits for population survival and demonstrate that rather specific conditions must be met to initiate the ‘diploid male vortex’.