Natural selection favours a larger eye in response to increased competition in natural populations of a vertebrate
Natural selection favours a larger eye in response to increased competition in natural populations of a vertebrate
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DOI：
10.1111/1365-2435.13334
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发表时间：
2019-07-01
影响因子：
5.2
通讯作者：
Walsh, Matthew R.
中科院分区：
文献类型：
--
作者：
Beston, Shannon M.;Walsh, Matthew R.
1.不同分类群的眼睛大小差异显着。许多研究表明，这种变化是由生态选择压力驱动的。然而，生态因素和眼睛大小的变化之间的关系的评估主要发生在宏观进化尺度。自然界的实验测试明显缺席。特立尼达鳉鱼，哈氏河，在捕食强度不同的鱼类群落中发现。我们最近发现，捕食的增加与眼睛变小的进化有关。在这里，我们测试了不同的捕食制度如何改变眼睛大小的演变轨迹，使用比较标记重捕获实验在多个流。我们发现，无论捕食强度如何，眼睛大小的增加都与生存率的提高有关。更重要的是，眼睛的大小与缺乏捕食者的群落的增长有关，而当捕食者存在时，这种趋势就不存在了。这些结果表明，在缺乏捕食者的地方，食物竞争的加剧是眼睛大小进化的关键驱动力。
1. Eye size varies notably across taxa. Much work suggests that this variation is driven by contrasting ecological selective pressures. However, evaluations of the relationship between ecological factors and shifts in eye size have largely occurred at the macroevolutionary scale. Experimental tests in nature are conspicuously absent.2. Trinidadian killifish, Rivulus hartii, are found across fish communities that differ in predation intensity. We recently showed that increased predation is associated with the evolution of a smaller eye. Here, we test how divergent predatory regimes alter the trajectory of eye size evolution using comparative mark-recapture experiments in multiple streams.3. We found that increases in eye size are associated with enhanced survival, irrespective of predation intensity. More importantly, eye size is associated with enhanced growth in communities that lack predators, while this trend is absent when predators are present.4. Such results argue that increased competition for food in sites that lack predators is the key driver of eye size evolution.