Ecological Opportunity and Diversification in a Continental Radiation of Birds: Climbing Adaptations and Cladogenesis in the Furnariidae
Ecological Opportunity and Diversification in a Continental Radiation of Birds: Climbing Adaptations and Cladogenesis in the Furnariidae
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DOI：
10.1086/664998
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发表时间：
2012-05-01
影响因子：
2.9
通讯作者：
Remsen, J. V., Jr.
中科院分区：
文献类型：
--
作者：
Claramunt, Santiago;Derryberry, Elizabeth P.;Remsen, J. V., Jr.
适应性辐射的生态学理论预测，生态机会通过其对竞争释放和生态位扩展的影响来刺激分支发生。考虑到关键的创新可能会带来生态机会，我们调查了收购攀登适应率的cladogenesis在一个主要的鸟类辐射，新热带区鸟类科科，使用物种水平的cladogenesis的影响。垂直攀爬的形态特化起源于2300万年前的爬山虎，远早于啄木鸟（啄木鸟科）或南美洲其他潜在竞争者的适应。这表明，获得攀爬适应赋予了充足的生态机会，早期的伐木。尽管如此，我们发现，物种形成率的增加，并不符合收购的攀登适应和攀登适应的积累和物种形成率之间的关系是负的。此外，我们没有检测到一个多样性依赖的下降，与树干攀爬生态位的饱和度一致的樵夫多样化率。这些研究结果不支持的假设，即生态机会相关的树干觅食刺激在这种辐射的分支。攀爬对多样化的负面影响可能是通过攀爬对扩散能力的间接正面影响来介导的，这可能会降低进化时间尺度上的物种形成率。
Ecological theories of adaptive radiation predict that ecological opportunity stimulates cladogenesis through its effects on competitive release and niche expansion. Given that key innovations may confer ecological opportunity, we investigated the effect of the acquisition of climbing adaptations on rates of cladogenesis in a major avian radiation, the Neotropical bird family Furnariidae, using a species-level phylogeny. Morphological specializations for vertical climbing originated in the woodcreepers similar to 23 million years ago, well before that adaptation occurred in woodpeckers (Picidae) or in other potential competitors in South America. This suggests that the acquisition of climbing adaptations conferred ample ecological opportunity to early woodcreepers. Nonetheless, we found that increases in speciation rates in Furnariidae did not coincide with the acquisition of climbing adaptations and that the relationship between the accumulation of climbing adaptations and rates of speciation was negative. In addition, we did not detect a diversity-dependent decline in woodcreeper diversification rates consistent with saturation of the trunk-climbing niche. These findings do not support the hypothesis that ecological opportunity related to trunk foraging stimulated cladogenesis in this radiation. The negative effect of climbing on diversification may be mediated by an indirect positive effect of climbing on dispersal ability, which may reduce speciation rates over evolutionary timescales.