据国外媒体报道,近日,科研人员经过长期的研究后发现,蜂后和南美切叶蚁后在一生中只有一天的性生活。在这特殊的一天中,蜂后和南美切叶蚁后和多个雄性性交,储存大量精子,其数量足够其用来繁衍后代。研究还发现,雄性蜜蜂或南美切叶蚁的精液可以在15分钟内杀死对手50%的精子,而蜂后和南美切叶蚁后同时也会选择合适的时机分泌出一种液体,保护最强壮的精子不受伤害。
西澳大利亚大学鲍里斯·贝尔(Boris Baer)称,雄性蜜蜂或雄性南美切叶蚁与蜂后或蚁后交配时,它们的精液可以杀死对手的精子,而精液在以前一直认为只是提供能量的含糖液体。同时,研究者还发现峰后或蚁后往往可以选择强壮的精子留在体内,以便繁衍后代。
贝尔和从丹麦哥本哈根大学来的同事一起,揭开了雄性蜜蜂和南美切叶蚁精液的秘密。研究者发现,雄性蜜蜂或南美切叶蚁的精液可以在15分钟内杀死对手50%的精子。贝尔说:“看起来是用精液杀死对手的精子。”
研究小组在熊蜂身上开展进一步实验。雌性熊蜂是一夫一妻制的忠实拥趸,在一生中只和一个雄性熊蜂性交。正如期望的那样,由于精子没有竞争对手,没有受到任何伤害。贝尔说,雄性昆虫的精液在一妻多夫制时可以保护和提高自身精子的生存率。这个结果表明,如脊椎动物的免疫系统一样,精液中具有识别“自身”和“非自身”的东西。
贝尔和他的同事还发现,南美切叶蚁后会分泌一种液体,可以阻止精液杀死对手精子。贝尔说,蚁后能够控制液体分泌的时机,以便让最强壮的精子能够留存体内来繁衍后代。(生物谷Bioon.com)
生物谷推荐原文出处:
Science DOI: 10.1126/science.1184709
Seminal Fluid Mediates Ejaculate Competition in Social Insects
Susanne P. A. den Boer,1 Boris Baer,2,3 Jacobus J. Boomsma1,*
Queens of ants and bees normally obtain a lifetime supply of sperm on a single day of sexual activity, and sperm competition is expected to occur in lineages where queens receive sperm from multiple males. We compared singly mated (monandrous) and multiply mated (polyandrous) sister groups of ants and bees and show that seminal fluid of polyandrous species has a more positive effect on the survival of a male’s own sperm than on other males’ sperm. This difference was not observed in the monandrous species, suggesting that incapacitation of competing sperm may have independently evolved in both bees and ants. In Atta leafcutter ants, the negative effect of the seminal fluid of other males was negated by secretion from the queen sperm-storage organ, suggesting that queens may control ejaculate competition after sperm storage.