Kivelä Sami M, Välimäki Panu, Carrasco David, Mäenpää Maarit I, Mänttäri Satu
Department of Biology, University of Oulu, PO Box 3000, 90014, Oulu, Finland.
Naturwissenschaften. 2012 Aug;99(8):607-16. doi: 10.1007/s00114-012-0940-2. Epub 2012 Jul 15.
A resource allocation trade-off is expected when resources from a common pool are allocated to two or more traits. In holometabolous insects, resource allocation to different functions during metamorphosis relies completely on larval-derived resources. At adult eclosion, resource allocation to the abdomen at the expense of other body parts can be seen as a rough estimate of resource allocation to reproduction. Theory suggests geographic variation in resource allocation to the abdomen, but there are currently no empirical data on it. We measured resource allocation to the abdomen at adult eclosion in four geometrid moths along a latitudinal gradient. Resource (total dry material, carbon, nitrogen) allocation to the abdomen showed positive allometry with body size. We found geographic variation in resource allocation to the abdomen in each species, and this variation was independent of allometry in three species. Geographic variation in resource allocation to the abdomen was complex. Resource allocation to the abdomen was relatively high in partially bivoltine populations in two species, which fits theoretical predictions, but the overall support for theory is weak. This study indicates that the geographic variation in resource allocation to the abdomen is not an allometric consequence of geographic variation in resource acquisition (i.e., body size). Thus, there is a component of resource allocation that can evolve independently of resource acquisition. Our results also suggest that there may be intraspecific variation in the degree of capital versus income breeding.
当来自一个共同资源库的资源被分配到两个或更多性状时，预计会出现资源分配的权衡。在全变态昆虫中，变态过程中分配到不同功能的资源完全依赖于幼虫期积累的资源。在成虫羽化时，以牺牲身体其他部位为代价向腹部的资源分配可被视为对繁殖资源分配的一个粗略估计。理论表明，向腹部的资源分配存在地理差异，但目前尚无相关实证数据。我们沿着纬度梯度测量了四种尺蛾成虫羽化时向腹部的资源分配情况。向腹部的资源（总干物质、碳、氮）分配与体型呈正异速生长关系。我们发现每个物种向腹部的资源分配都存在地理差异，并且在三个物种中这种差异与异速生长无关。向腹部的资源分配的地理差异很复杂。在两个物种的部分二化性种群中，向腹部的资源分配相对较高，这符合理论预测，但对该理论的总体支持较弱。这项研究表明，向腹部的资源分配的地理差异并非资源获取（即体型）地理差异的异速生长结果。因此，存在一部分资源分配可以独立于资源获取而进化。我们的结果还表明，在资本繁殖与收入繁殖的程度上可能存在种内变异。
