Competitive asymmetry and local adaptation in Trinidadian guppies
Competitive asymmetry and local adaptation in Trinidadian guppies
复制标题
特立尼达孔雀鱼的竞争不对称和局部适应
DOI：
10.1111/1365-2656.12918
复制
发表时间：
2018
影响因子：
4.8
通讯作者：
R. Bassar
中科院分区：
文献类型：
--
作者：
T. Potter;L. King;J. Travis;R. Bassar
个体之间竞争的结果往往取决于身体的大小。这些竞争的不对称性可以驱动人口比率的变化，影响生态和生命史的进化。这种不对称性的大小和方向不同类群，但很少有人知道如何适应资源限制改变竞争的不对称性经验。在这里，我们研究规模依赖的竞争能力和适应资源限制之间的关系。我们研究了大小依赖的竞争，在两个生态型的特立尼达孔雀鱼，适应高或低水平的资源竞争。使用水族馆为基础的竞争实验，我们描述了竞争对手的大小和生态类型如何影响体细胞生长速率，同时控制生态位分化的混杂效应。我们复制了我们的研究在两个独立的进化起源的“竞争”生态型。这两个“竞争”的生态型显着不同的大小依赖的不对称性，表明适应资源限制本身是不足以解释的变化大小依赖的竞争不对称性。对于一个起源，适应资源限制的生态型是一个上级的竞争对手在很大范围内的大小配对。竞争对手的等价物变化超过五倍，取决于大小和生态类型;在四个种群中的三个中，较大的个体具有竞争优势。我们的研究结果表明，竞争不对称对体细胞生长有很强的影响。由于体细胞生长有助于人口统计参数，种内性状变异可能在调节人口统计率方面发挥关键作用。我们的研究结果意味着，在激烈的竞争条件下，规模依赖的不对称性的演变可能会受到限制的利基可用性，但需要进一步的研究来验证这一点。
The outcome of competition between individuals often depends on body size. These competitive asymmetries can drive variation in demographic rates, influencing the ecology and evolution of life histories. The magnitude and direction of such asymmetries differ among taxa, yet little is known empirically about how adaptation to resource limitation alters competitive asymmetries. Here, we investigate the relationship between size-dependent competitive ability and adaptation to resource limitation. We examined size-dependent competition in two ecotypes of Trinidadian guppy, adapted to high or low levels of resource competition. Using aquaria-based competition experiments, we describe how the size and ecotype of competitors influence somatic growth rate, whilst controlling for the confounding effect of niche differentiation. We replicated our study across two independent evolutionary origins of the "competitive" ecotype. The two "competitive" ecotypes differed markedly in size-dependent asymmetry, indicating that adaptation to resource limitation alone is insufficient to explain changes in size-dependent competitive asymmetry. For one origin, the ecotype adapted to resource limitation was a superior competitor over a wide range of size pairings. The equivalence of competitors varied over fivefold, dependent on size and ecotype; in three of four populations, larger individuals had a competitive advantage. Our results demonstrate that competitive asymmetry has strong effects on somatic growth. Because somatic growth contributes to demographic parameters, intraspecific trait variation is likely to play a key role in regulating demographic rates. Our findings imply that the evolution of size-dependent asymmetries under conditions of intense competition is likely to be constrained by niche availability, although further research is needed to verify this.
影响因子：
16.8
作者：
Arne Schröder;A. van Leeuwen;T. Cameron
通讯作者：
Arne Schröder;A. van Leeuwen;T. Cameron