Warwick Alexa R, Travis Joseph, Lemmon Emily Moriarty
Department of Biological Science, Florida State University, 319 Stadium Drive, Tallahassee, FL, 32306, USA.
Mol Ecol. 2015 Jul;24(13):3281-98. doi: 10.1111/mec.13242. Epub 2015 Jun 15.
Delimiting species is important to every subfield in biology. Templeton's cohesion species concept uses genetic and ecological exchangeability to identify sets of populations that ought to be considered as the same species, and the lack of exchangeability helps determine which populations can be grouped as evolutionarily significant units (ESU) in conservation science. However, previous work assessing genetic and ecological interchangeability among populations has been limited in scope. Here, we provide a method for assessing exchangeability that incorporates multiple, independent lines of multivariate evidence in genetic, behavioural and morphological data. We use this approach to assess exchangeability across three disjunct groups of populations of the Pine Barrens Treefrog (Hyla andersonii) from the eastern United States. This species is considered threatened by each state in which it occurs and conservation management of this taxon requires a clearer understanding of how populations in these three regions may differ from one another. We find a strikingly concordant pattern in which the first axis of variation for each of the three types of data distinguishes populations along a latitudinal gradient and the second axis distinguishes the set of populations occurring in the Carolinas from those occurring in the New Jersey and Florida/Alabama regions. We know of no comparable data set that displays such concordance among different types of data across so large a geographic range. The overlap in trait values (i.e. exchangeability) between neighbouring regions, however, is substantial in all three types of data, which supports continued consideration of this taxon as a single species.
界定物种对生物学的每个子领域都很重要。坦普尔顿的凝聚种概念利用遗传和生态可交换性来识别应被视为同一物种的种群集合，而缺乏可交换性有助于确定哪些种群可被归类为保护科学中具有进化意义的单元（ESU）。然而，先前评估种群间遗传和生态互换性的工作在范围上受到限制。在此，我们提供一种评估可交换性的方法，该方法整合了遗传、行为和形态数据中多条独立的多变量证据线。我们使用这种方法来评估来自美国东部的贫瘠松林雨蛙（Hyla andersonii）三个不连续种群组的可交换性。该物种在其出现的每个州都被视为受威胁物种，对这个分类单元的保护管理需要更清楚地了解这三个地区的种群可能如何彼此不同。我们发现了一个惊人的一致模式，即三种数据类型中每种数据的第一变异轴沿纬度梯度区分种群，第二轴区分卡罗来纳州出现的种群与新泽西州和佛罗里达州/阿拉巴马州地区出现的种群。我们所知的没有可比数据集能在如此大的地理范围内不同类型的数据之间显示出这种一致性。然而，在所有三种数据类型中，相邻区域之间的性状值重叠（即可交换性）都很大，这支持将这个分类单元继续视为单一物种。
