Evolutionary Ecology of sex-ratio variation in Tigriopus

虎鱼性别比例变异的进化生态学

基本信息

批准号：
RGPIN-2015-06224
负责人：
Anholt, Bradley
金额：
$ 2.33万
依托单位：
University of Victoria
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2022
资助国家：
加拿大
起止时间：
2022-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745600
关键词：
Evolutionary Ecology sex ratio variation

项目摘要

Understanding why sex ratio is usually equal and predicting when it should deviate from equality is one of the success stories of evolutionary biology. However, in diploid organisms there is very little variation for sex ratio so the supporting data is almost all observational. The small crustacean copepod Tigriopus californicus has heritable variation for sex ratio and extraordinarily wide phenotypic variation in sex ratio. It produces its first eggs three weeks after hatching, and females mate only once, which makes sequential clutches full sibs. This makes it ideal to test sex ratio theory experimentally. This animal lives in the splash zone above the high tide line in small pools that frequently dry out. Populations are maintained by frequent dispersal. They are easily maintained in the laboratory and experimental breeding programs are easy to implement. My research group has been able to create selected lines that are reliably biased towards producing male or female biased clutches of offspring. A Quantitative Trait Locus study showed that there are at least 6 loci on 5 (of 12) chromosomes that are significantly associated with clutch sex ratio.This research program seeks to accomplish the following. 1) Understand the unusual features of the Tigriopus sex-determination system. 2) Determine whether population subdivision maintains the wide variation in sex ratio seen in Tigriopus using both theoretical and experimental approaches. 3) Use experimental evolution to test the predictions of sex-ratio theory. Studies of experimental evolution will be supplemented with high-throughput genomic methods to ascertain whether there are repeatable patterns in the genetic changes associated with evolutionary changes in the sex-ratio phenotype.

理解为什么性别比例通常是相等的并预测何时应该偏离平等是进化生物学的成功故事之一。然而，在二倍体生物中，性别比例的变化非常小，因此支持数据几乎都是小型甲壳类动物。桡足类 Tigriopus californicus 的性别比例具有遗传性变异，并且性别比例的表型变异非常广泛，它在孵化后三周产下第一颗卵，雌性仅交配一次，这使得连续的窝产满。这使得通过实验测试性别比例理论变得理想。这种动物生活在高潮线以上的小水池中，通过频繁的分散来维持它们的种群。计划很容易实施。我的研究小组已经能够创建出可靠地偏向于产生雄性或雌性后代的选定品系。一项定量性状基因座研究表明，至少有5 个（共 12 个）染色体上的 6 个基因座与窝性别比例显着相关。本研究计划旨在实现以下目标：1) 了解虎纹龙性别决定系统的不寻常特征；2) 确定种群细分是否保持广泛。使用理论和实验方法观察虎属性别比例的变化 3) 使用实验进化来检验性别比例理论的预测。辅以高通量基因组方法，以确定与性别比例表型进化变化相关的遗传变化是否存在可重复的模式。