...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of genetics >Evolution of increased larval competitive ability in Drosophila melanogaster without increased larval feeding rate
【24h】

Evolution of increased larval competitive ability in Drosophila melanogaster without increased larval feeding rate

机译：果蝇摄食率提高而果蝇幼虫竞争能力的演变

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Multiple experimental evolution studies on Drosophila melanogaster in the 1980s and 1990s indicated that enhanced competitive ability evolved primarily through increased larval tolerance to nitrogenous wastes and increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and this became the widely accepted view of how adaptation to larval crowding evolves in fruitflies. We recently showed that populations of D. ananassae and D. n. nasuta subjected to extreme larval crowding evolved greater competitive ability without evolving higher feeding rates, primarily through a combination of reduced larval duration, faster attainment of minimum critical size for pupation, greater efficiency of food conversion to biomass, increased pupation height and, perhaps, greater urea/ammonia tolerance. This was a very different suite of traits than that seen to evolve under similar selection in D. melanogaster and was closer to the expectations from the theory of K-selection. At that time, we suggested two possible reasons for the differences in the phenotypic correlates of greater competitive ability seen in the studies with D. melanogaster and the other two species. First, that D. ananassae and D. n. nasuta had a very different genetic architecture of traits affecting competitive ability compared to the long-term laboratory populations of D. melanogaster used in the earlier studies, either because the populations of the former two species were relatively recently wild-caught, or by virtue of being different species. Second, that the different evolutionary trajectories in D. ananassae and D. n. nasuta versus D. melanogaster were a reflection of differences in the manner in which larval crowding was imposed in the two sets of selection experiments. The D. melanogaster studies used a higher absolute density of eggs per unit volume of food, and a substantially larger total volume of food, than the studies on D. ananassae and D. n. nasuta. Here, we show that long-term laboratory populations of D. melanogaster, descended from some of the populations used in the earlier studies, evolve essentially the same set of traits as the D. ananassae and D. n. nasuta crowding-adapted populations when subjected to a similar larval density at low absolute volumes of food. As in the case of D. ananassae and D. n. nasuta, and in stark contrast to earlier studies with D. melanogaster, these crowding-adapted populations of D. melanogaster did not evolve greater larval feeding rates as a correlate of increased competitive ability. The present results clearly suggest that the suite of phenotypes through which the evolution of greater competitive ability is achieved in fruitflies depends critically not just on larval density per unit volume of food, but also on the total amount of food available in the culture vials. We discuss these results in the context of an hypothesis about how larval density and the height of the food column in culture vials might interact to alter the fitness costs and benefits of increased larval feeding rates, thus resulting in different routes to the evolution of greater competitive ability, depending on the details of exactly how the larval crowding was implemented.
机译：在1980年代和1990年代对果蝇进行的多项实验进化研究表明，增强的竞争能力主要是通过提高对含氮废物的幼虫耐受性以及提高幼虫的饲喂和觅食率而产生的，而这是以食物转化为生物质的效率为代价的，这已成为广泛的关于果蝇如何适应幼虫拥挤的公认观点。我们最近显示了D. ananassae和D. n。的种群。遭受极端幼虫拥挤的纳沙塔在不提高饲喂率的情况下发展出更大的竞争能力，这主要是通过减少幼虫持续时间，更快达到化粪的最小临界尺寸，提高食物转化为生物质的效率，增加化粪的高度以及可能更大的组合尿素/氨耐受性。这与黑腹果蝇在类似选择下进化出的特征完全不同，并且更接近于钾选择理论的期望。当时，我们提出了两个可能的原因，以研究黑腹果蝇和其他两个物种的竞争能力较高的表型相关性。首先，那是D. ananassae和D. n.。与早期研究中长期使用的D. melanogaster实验室种群相比，nasuta的遗传结构对竞争能力的影响有很大不同，这可能是因为前两个物种的种群是相对较新的野生捕获，或者是由于是不同的物种。其次，在D. ananassae和D. n。中不同的进化轨迹。 nasuta与D. melanogaster的差异反映了两组选择实验中幼虫拥挤的方式差异。与D. ananassae和D. n。的研究相比，D。melanogaster的研究使用的每单位食物体积的卵的绝对密度更高，而食物的总体积则大得多。 nasuta。在这里，我们表明，D。melanogaster的长期实验室种群是早期研究中使用的一些种群的后代，其进化的特征与D. ananassae和D. n。基本相同。在绝对绝对食物含量低的情况下，类似幼虫密度的纳苏塔人群适应种群。如D. ananassae和D. n。 nasuta，与早期对D. melanogaster的研究形成鲜明对比的是，这些拥挤适应的D. melanogaster种群没有进化出更高的幼虫摄食率，这与竞争能力的提高相关。目前的结果清楚地表明，通过一系列表型在果蝇中实现更大的竞争能力不仅取决于单位体积食物的幼虫密度，而且还取决于培养瓶中可用食物的总量。我们在假说的背景下讨论这些结果，假说是关于培养瓶中的幼虫密度和食物柱的高度可能如何相互作用以改变适应性成本以及增加幼虫摄食率的好处，从而导致竞争性竞争发展的途径不同能力，具体取决于幼虫拥挤如何实施的细节。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号