Natural selection drives the fine-scale divergence of a coevolutionary arms race involving a long-mouthed weevil and its obligate host plant.
Natural selection drives the fine-scale divergence of a coevolutionary arms race involving a long-mouthed weevil and its obligate host plant.
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DOI：
10.1186/1471-2148-9-273
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发表时间：
2009-11-27
影响因子：
3.4
通讯作者：
Toju H
中科院分区：
文献类型：
--
作者：
Toju H
进化生物学最近的主要进展之一是认识到物种之间的进化相互作用在不同的地理种群之间有很大的差异。到目前为止，几位作者已经揭示了自然选择压力调节了地理上不同的共同进化过程。那么，在共同进化系统中，自然选择的地理结构是如何定位的呢？我研究了“地理选择马赛克”的空间尺度，重点研究了一个涉及种子捕食性昆虫山茶象甲(Curculio Camelliae)及其寄主植物日本山茶(Camellia Japan Onica)的系统。在这个系统中，雌性象甲用它们极长的口器挖掘山茶花的果实，将卵产卵成种子，而山茶籽则被厚厚的果皮保护着。对自然选择的定量评估表明，较厚的山茶果皮在一个小岛(日本八岛，直径约30公里)内的一些(但不是所有)种群中明显受到青睐。在极端情况下，相距只有几公里的茶花种群受到不同的选择压力。有趣的是，在果皮最厚的种群中，当考虑到生产厚皮的潜在成本时，具有中等果皮厚度的茶树个体具有相对较高的适合度。同样重要的是，象甲-山茶相互作用的一些参数，如种子侵染的严重程度，显示出沿温度的倾斜性，这表明气候对共同进化过程的精细地理分化的影响。这些结果表明，自然选择可以在令人惊讶的小空间尺度上推动种间相互作用的地理分化。未来的研究应该会揭示生物群落中“精细地理马赛克”的进化/生态结果。
One of the major recent advances in evolutionary biology is the recognition that evolutionary interactions between species are substantially differentiated among geographic populations. To date, several authors have revealed natural selection pressures mediating the geographically-divergent processes of coevolution. How local, then, is the geographic structuring of natural selection in coevolutionary systems? I examined the spatial scale of a "geographic selection mosaic," focusing on a system involving a seed-predatory insect, the camellia weevil (Curculio camelliae), and its host plant, the Japanese camellia (Camellia japonica). In this system, female weevils excavate camellia fruits with their extremely-long mouthparts to lay eggs into seeds, while camellia seeds are protected by thick pericarps. Quantitative evaluation of natural selection demonstrated that thicker camellia pericarps are significantly favored in some, but not all, populations within a small island (Yakushima Island, Japan; diameter ca. 30 km). At the extreme, camellia populations separated by only several kilometers were subject to different selection pressures. Interestingly, in a population with the thickest pericarps, camellia individuals with intermediate pericarp thickness had relatively high fitness when the potential costs of producing thick pericarps were considered. Also importantly, some parameters of the weevil - camellia interaction such as the severity of seed infestation showed clines along temperature, suggesting the effects of climate on the fine-scale geographic differentiation of the coevolutionary processes. These results show that natural selection can drive the geographic differentiation of interspecific interactions at surprisingly small spatial scales. Future studies should reveal the evolutionary/ecological outcomes of the "fine scale geographic mosaics" in biological communities.
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影响因子：
3.3
作者：
ARNOLD, SJ;WADE, MJ
通讯作者：
WADE, MJ
影响因子：
3.3
作者：
Fornoni, J;Valverde, PL;Núñez-Farfán, J
通讯作者：
Núñez-Farfán, J
影响因子：
3.3
作者：
BERTNESS, MD;GARRITY, SD;LEVINGS, SC
通讯作者：
LEVINGS, SC
影响因子：
3.3
作者：
Benkman, CW;Holimon, WC;Smith, JW
通讯作者：
Smith, JW
影响因子：
2.6
作者：
Brodie, ED;Ridenhour, BJ
通讯作者：
Ridenhour, BJ