The role of rare morph advantage and conspicuousness in the stable gold‐dark colour polymorphism of a crater lake Midas cichlid fish
The role of rare morph advantage and conspicuousness in the stable gold‐dark colour polymorphism of a crater lake Midas cichlid fish
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稀有形态优势和显着性在火山口湖迈达斯慈鲷稳定的金色-深色多态性中的作用
DOI：
10.1111/1365-2656.12693
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发表时间：
2017
影响因子：
4.8
通讯作者：
A. Meyer
中科院分区：
文献类型：
--
作者：
Torres-Dowdall;Golcher-Benavides;A. Meyer
基于遗传的稳定的颜色多态性提供了一个独特的机会，研究在野生环境中保存遗传变异的进化过程。目前，国内外学者提出了不同的促进多态性稳定性的机制，但相关的实证研究较少，导致对这些机制的理解不全面。所有的米达斯慈鲷开始他们的生活与深灰色的颜色（黑暗形态），但个人携带占主导地位的“黄金”等位基因（c。10%）在以后的生活中失去了他们的黑色素细胞，揭示了潜在的橙子颜色（金色形态）。这种多态性是如何维持的尚不清楚。已经提出了两个主要的假设，这两个建议作为近似机制的颜色变体上的差异捕食。有人预测，显眼的金色变体更有可能被捕食，但这种劣势被它们对黑暗变体的竞争优势所平衡。第二个假设表明，一种罕见的变形优势，其中罕见的黄金变形经验较少的捕食。这些机制的经验证据仍然是间接的和inconclusive.We进行了两个现场实验，在一个Xuanuan火山口湖使用蜡模型模拟两种形态，以确定捕食压力后，迈达斯慈鲷色morphs。首先，我们测试了颜色和深度对攻击率的相互作用。其次，我们测试了鱼的大小和颜色的相互作用。我们将这些实验中的攻击模式与解释颜色多态性稳定性的假设中预测的捕食模式进行了对比。无论它们在水柱中的位置如何，模仿颜色多态性的大型模型都以相似的速率受到攻击。然而，对类似青少年的小模型的攻击主要针对黑暗模型。这导致了一个显着的大小由颜色的相互作用。我们认为，金迈达斯慈鲷经历了一个罕见的变形优势作为青少年时，这种变形的个人是非常罕见的。但这种影响在成年人中减少或消失，其中黄金个体相对更常见。因此，罕见的形态优势和显着性的相互作用，而不是这些因素单独的，是一个可能的机制，导致在米达斯慈鲷的颜色多态性的稳定性。
Genetically based stable colour polymorphisms provide a unique opportunity to study the evolutionary processes that preserve genetic variability in the wild. Different mechanisms are proposed to promote the stability of polymorphisms, but only few empirical examples have been documented, resulting in an incomplete understanding of these mechanisms.A remarkable genetically determined stable colour polymorphism is found in the Nicaraguan Midas cichlid species complex (Amphilophuscf.citrinellus). All Midas cichlids start their life with a dark‐grey coloration (dark morph), but individuals carrying the dominant “gold” allele (c. 10%) lose their melanophores later in life, revealing the underlying orange coloration (gold morph). How this polymorphism is maintained remains unclear. Two main hypotheses have been proposed, both suggesting differential predation upon colour morphs as the proximate mechanism. One predicts that the conspicuous gold morph is more likely to be preyed upon, but this disadvantage is balanced by their competitive dominance over the dark morph. The second hypothesis suggests a rare morph advantage where the rarer gold morph experiences less predation. Empirical evidence for either of these mechanisms is still circumstantial and inconclusive.We conducted two field experiments in a Nicaraguan crater lake using wax models simulating both morphs to determine predation pressure upon Midas cichlid colour morphs. First, we tested the interaction of coloration and depth on attack rate. Second, we tested the interaction of fish size and coloration. We contrasted the pattern of attacks from these experiments to the predicted predation patterns from the hypotheses proposed to explain the colour polymorphism's stability.Large models imitating colour morphs were attacked at similar rates irrespectively of their position in the water column. Yet, attacks upon small models resembling juveniles were directed mainly towards dark models. This resulted in a significant size‐by‐colour interaction.We suggest that gold Midas cichlids experience a rare morph advantage as juveniles when individuals of this morph are extremely uncommon. But this effect is reduced or disappears among adults, where gold individuals are relatively more common. Thus, the interaction of rare morph advantage and conspicuousness, rather than either of those factors alone, is a likely mechanism resulting in the stability of the colour polymorphism in Midas cichlids.
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多色 Midas Cichlid Cichlasoma citrinellum 颜色变形之间的竞争
影响因子：
56.9
作者：
G. Barlow
通讯作者：
G. Barlow
捕食者社区的季节性变化切换了猎物防御的选择方向。
影响因子：
16.6
作者：
Mappes, Johanna;Kokko, Hanna;Ojala, Katja;Lindstrom, Leena
通讯作者：
Lindstrom, Leena
影响因子：
3.3
作者：
Elmer, Kathryn R.;Lehtonen, Topi K.;Meyer, Axel
通讯作者：
Meyer, Axel
影响因子：
3.3
作者：
M. Turelli;N. H. Barton
通讯作者：
M. Turelli;N. H. Barton
DOI：
--
发表时间：
2015-10
期刊：
--
影响因子：
--
作者：
Douglas M. Bates;M. Maechler;Ben Bolker;Steven C. Walker
通讯作者：
Douglas M. Bates;M. Maechler;Ben Bolker;Steven C. Walker