Selection and Admixture in a Polytypic Aposematic Frog
Selection and Admixture in a Polytypic Aposematic Frog
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DOI：
10.1086/722559
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发表时间：
2023-02-01
影响因子：
2.9
通讯作者：
Richards-Zawacki，Corinne L.
中科院分区：
文献类型：
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作者：
Yeager，Justin;Derryberry，Graham E.;Richards-Zawacki，Corinne L.
多型物种内的表型分化通常归因于选择，特别是当选择可能作用于作为捕食者回避和配偶选择信号的性状时。我们评估了这一假设，通过研究草莓毒蛙Oophaga pumilio，一个多型物种，表现出警戒色图案的变化，被认为是受自然和性选择的人口之间的表型和基因型的倾斜。我们的目的是评估混合的程度，并估计选择的强度作用于着色在巴拿马的一个地区，单态种群的明显有色青蛙分离的多态性种群包含两种颜色的变种，旁边的中间着色的个人。我们在整个研究区域检测到了尖锐的倾斜过渡，这是强选择的预期结果，但我们也检测到了广泛混合的证据，即使在远离表型过渡区的地点。此外，基因型和表型渐变系既不一致也不一致，有一个例外，从渐变系属性估计的选择系数很小。这些结果表明，强选择是不需要的多型物种内的表型分化的维护，挑战长期存在的观念，强选择是隐含在进化的警告信号。
Phenotypic differentiation within polytypic species is often attributed to selection, particularly when selection might be acting on a trait that serves as a signal for predator avoidance and mate choice. We evaluated this hypothesis by examining phenotypic and genotypic clines between populations of the strawberry poison frogOophaga pumilio, a polytypic species that exhibits aposematic color pattern variation that is thought to be subject to both natural and sexual selection. Our aim was to assess the extent of admixture and to estimate the strength of selection acting on coloration across a region of Panama where monomorphic populations of distinctly colored frogs are separated by polymorphic populations containing both color variants alongside intermediately colored individuals. We detected sharp clinal transitions across the study region, which is an expected outcome of strong selection, but we also detected evidence of widespread admixture, even at sites far from the phenotypic transition zone. Additionally, genotypic and phenotypic clines were neither concordant nor coincident, and with one exception, selection coefficients estimated from cline attributes were small. These results suggest that strong selection is not required for the maintenance of phenotypic divergence within polytypic species, challenging the long-standing notion that strong selection is implicit in the evolution of warning signals.