A TEST OF THE ENDOGENOUS AND EXOGENOUS SELECTION HYPOTHESES FOR THE MAINTENANCE OF A NARROW AVIAN HYBRID ZONE
A TEST OF THE ENDOGENOUS AND EXOGENOUS SELECTION HYPOTHESES FOR THE MAINTENANCE OF A NARROW AVIAN HYBRID ZONE
复制标题
维持狭窄鸟类杂交区的内源和外源选择假说的检验
DOI：
10.1111/j.0014-3820.2003.tb01554.x
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
M. Braun
中科院分区：
文献类型：
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作者：
C. L. Bronson;T. Grubb;M. Braun
遗传和环境因素对杂交区差异繁殖成功的影响很少被研究。在这里，我们报告了一项操作实验，同时测试了杂交区内的内源（基于遗传）和外源（基于环境）选择。将两种山雀（Poecile atricapilla和P. carolinensis）及其杂交种的交配对移植到其杂交区内的孤立林地中，并对其繁殖成功率进行了监测。尽管卵群大小相似，但基于对一对遗传兼容性的估计，杂交对产生的雏鸟和雏鸟比任何一对亲本物种都要少。根据数据生成的线性模型，一对亲本物种的纯种配对在每次筑巢尝试中产生的雏鸟分别是实验中平均配对或最不相容配对的1.91-2.48倍。我们的研究结果表明，在相同的环境下（本实验中的杂交区），杂交对相对于亲本物种对的繁殖减少，这支持了维持杂交区的内源选择假说。由于实验完全是在杂交区进行的（即亲本和杂交配对的相同环境），我们的数据不支持外源选择假说，因为它预测所有配对都表现不佳，或者杂交配对比亲本配对更成功。
Abstract The contributions of genetic and environmental factors to differential reproductive success across hybrid zones have rarely been tested. Here, we report a manipulative experiment that simultaneously tested endogenous (genetic-based) and exogenous (environmental-based) selection within a hybrid zone. We transplanted mated pairs of two chickadee species (Poecile atricapilla and P. carolinensis) and their hybrids into isolated woodlots within their hybrid zone and monitored their reproductive success. Although clutch sizes were similar, based on an estimate of the genetic compatibility of a pair, hybrid pairs produced fewer nestlings and fledglings than did pairs of either parental species. According to a linear model generated from the data, a pure pair of either parental species would be expected to produce 1.91–2.48 times more fledglings per nesting attempt, respectively, than the average or least compatible pair in the experiment. Our result of decreased reproduction for hybrid pairs relative to parental species pairs within same environment (the hybrid zone in this experiment) support the endogenous selection hypothesis for maintenance of this hybrid zone. Because the experiment was conducted entirely within the hybrid zone (i.e., the same environment for parental and hybrid pairings), our data do not support the exogenous selection hypothesis as it predicts either all pairings doing poorly or the hybrid pairs more successful than the parental pairs.