Possibility of sperm competition in spermathecae of ants

蚂蚁受精囊中精子竞争的可能性

基本信息

批准号：
07640829
负责人：
HIGASHI Seigo
金额：
$ 1.41万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

CAP-PCR DNA Fingerprinting method was used for estimating the insemination frequency of ant queens, because this method had the following advantages for analyzing kin relatedness : 1) The required amount of DNA was as small as 50 ng, which is available even from very tiny insects. 2) The variation of band pattern was large and only a few individuals or colonies were required for the analysis of kin relatedness. 3) Band patterns from the same sample were almost always identical ; thus, the reproducibility was very high. Accordingly, queens of most ant species were monandrous and only a few species showed polyandry. That is, sperm cells of different males rarely coexist in a spermatheca of a queen. Probably because of this, I could not find any evidence of sperm competition in the present study.Nonetheless, some sociobiologically important results were obtained in this study : 1) In the tribe Attini which is distributed in South and Central America, such socially higher genera as Atta, Acromymex and Sericomyrmex were polyandrous, while lower genera such as Cyphomyrmex and Myrmicocrypta showed monandry. This suggests that the polyandry contributes to the evolution of effective polyethism and huge societies of social insects. 2) As theoretically predicted, the sex ratio was distorted to females in the monandrous species, though the ratio of the females decreased in the polyandrous species. In Atta the sex ratio was obviously distorted to males for unknown reasons. 3) Fungi were the staple food of larvae and queens but not of abult workers, unlike the prediction of four hypotheses which have been proposed to account for the evolution of mycophagy in Attini. This means that another hypothesis have to be considered under the condition that the mycophagy evolved for lavae.

CAP-PCR DNA指纹方法用于估计蚂蚁皇后的授精频率，因为该方法具有以下优势分析亲属相关性的优势：1）所需的DNA量高达50 ng，即使从非常微小的昆虫中也可以使用。 2）带模式的变化很大，分析亲属相关性需要少数个个体或菌落。 3）来自同一样品的带模式几乎总是相同的；因此，可重复性非常高。因此，大多数蚂蚁物种的皇后是单鼠，只有少数物种表现出一夫多妻。也就是说，不同男性的精子细胞很少在女王的精子中共存。 Probably because of this, I could not find any evidence of sperm competition in the present study.Nonetheless, some sociobiologically important results were obtained in this study : 1) In the tribe Attini which is distributed in South and Central America, such socially higher genera as Atta, Acromymex and Sericomyrmex were polyandrous, while lower genera such as Cyphomyrmex and Myrmicocrypta showed monandry.这表明一夫多妻制促进了有效的聚会主义和庞大的社会昆虫社会的演变。 2）如从理论上预测的那样，尽管多种物种的女性之比降低了，但性别比例扭曲为单虫物种中的女性。在atta中，由于未知原因，性别比显然被扭曲为男性。 3）真菌是幼虫和皇后区的主食，而不是雄伟的工人的主食，这与预测四个假设的预测是为了解释阿蒂尼尼菌落的演变。这意味着必须在霉菌进化为乳脂的条件下考虑另一个假设。