The geographic mosaic in parallel: Matching patterns of newt tetrodotoxin levels and snake resistance in multiple predator–prey pairs
The geographic mosaic in parallel: Matching patterns of newt tetrodotoxin levels and snake resistance in multiple predator–prey pairs
复制标题
平行的地理马赛克：多个捕食者与猎物对中蝾螈河豚毒素水平和蛇抗性的匹配模式
DOI：
10.1111/1365-2656.13212
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发表时间：
2020
影响因子：
4.8
通讯作者：
Feldman, Chris R.
中科院分区：
文献类型：
--
作者：
Reimche, Jessica S.;Brodie, Jr., Edmund D.;Stokes, Amber N.;Ely, Erica J.;Moniz, Haley A.;Thill, Vicki L.;Hallas, Joshua M.;Pfrender, Michael E.;Brodie, III, Edmund D.;Feldman, Chris R.
共同进化的地理镶嵌理论预测，共同进化的军备竞赛将随着时间和空间的变化而变化，因为不同的生态环境和相互作用的物种在整个景观中的种群历史。因此，理解共同进化可能需要调查在相互作用范围内取样的广泛群体。此外，比较相似系统之间的共同进化动力学可能揭示结构共同进化的特定因素的重要性。在这里，我们研究了相对未研究的塞拉利昂束带蛇（Thamnophis couchii）和同域猎物，粗皮蝾螈（Taricha granulosa），塞拉利昂蝾螈（Ta. sierelae）和加州蝾螈（Ta. torosa）。这个系统在空间和表型上与捕食性普通束带蛇（Th. sirtalis）及其有毒蝾螈猎物，表现出蝾螈河豚毒素（TTX）水平的热点并与蛇的TTX抗性相匹配。我们量化了分布范围内数百个个体的猎物和捕食者特征，并在同域地点进行了功能特征匹配。我们在Th的共享范围内显示了特征协变的强烈区域模式。蝾螈的猎物。不同地区的特性差异很大，北方纬度的蝾螈TTX水平和蛇TTX抗性较低，而南方纬度的蝾螈TTX水平和蛇抗性较高。北方种群中的蝾螈和蛇尽管具有最少的极端特征，但表现出最高程度的功能特征匹配。相反，南部种群中的蝾螈和蛇表现出最大的不匹配，尽管它们具有夸张的特征，一些蛇对TTX具有很强的抵抗力，它们不会受到任何同域蝾螈的影响。尽管如此，个体差异是巨大的，似乎提供了机会，在大多数种群中继续相互选择。总体而言，这三种蝾螈似乎是从事TTX介导的军备竞赛与Th。库奇这些模式与蝾螈和Th之间的模式一致。sirtalis，包括相同的纬度梯度的性状协变，和潜在的“逃避”的军备竞赛的蛇捕食者。两个不同系统的大尺度模式的一致性表明，共同的现象可能以类似的方式构建地理马赛克。
The Geographic Mosaic Theory of Coevolution predicts that coevolutionary arms races will vary over time and space because of the diverse ecological settings and population histories of interacting species across the landscape. Thus, understanding coevolution may require investigating broad sets of populations sampled across the range of the interaction. In addition, comparing coevolutionary dynamics between similar systems may reveal the importance of specific factors that structure coevolution.Here, we examine geographic patterns of prey traits and predator traits in the relatively unstudied interaction between the Sierra garter snake (Thamnophis couchii) and sympatric prey, the rough‐skinned newt (Taricha granulosa), Sierra newt (Ta. sierrae) and California newt (Ta. torosa). This system parallels, in space and phenotypes, a classic example of coevolution between predatory common garter snakes (Th. sirtalis) and their toxic newt prey exhibiting hotspots of newt tetrodotoxin (TTX) levels and matching snake TTX resistance.We quantified prey and predator traits from hundreds of individuals across their distributions, and functional trait matching at sympatric sites.We show strong regional patterns of trait covariation across the shared ranges ofTh. couchiiand newt prey. Traits differ significantly among localities, with lower newt TTX levels and snake TTX resistance at the northern latitudes, and higher TTX levels and snake resistance at southern latitudes. Newts and snakes in northern populations show the highest degree of functional trait matching despite possessing the least extreme traits. Conversely, newts and snakes in southern populations show the greatest mismatch despite possessing exaggerated traits, with some snakes so resistant to TTX they would be unaffected by any sympatric newt. Nevertheless, individual variation was substantial, and appears to offer the opportunity for continued reciprocal selection in most populations.Overall, the three species of newts appear to be engaged in a TTX‐mediated arms race withTh. couchii. These patterns are congruent with those seen between newts andTh. sirtalis, including the same latitudinal gradient in trait covariation, and the potential ‘escape’ from the arms race by snake predators. Such concordance in broad scale patterns across two distinct systems suggests common phenomena might structure geographic mosaics in similar ways.