Department of Ornithology, American Museum of Natural History, Central Park West at 79th Street, New York, NY, 10024, USA.
Departamento de Genética e Biologia Evolutiva, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, São Paulo, SP, 05508-090, Brazil.
Nat Commun. 2021 Nov 1;12(1):6269. doi: 10.1038/s41467-021-26537-9.
Tropical mountains hold more biodiversity than their temperate counterparts, and this disparity is often associated with the latitudinal climatic gradient. However, distinguishing the impact of latitude versus the background effects of species history and traits is challenging due to the evolutionary distance between tropical and temperate assemblages. Here, we test whether microevolutionary processes are linked to environmental variation across a sharp latitudinal transition in 21 montane birds of the southern Atlantic Forest in Brazil. We find that effective dispersal within populations in the tropical mountains is lower and genomic differentiation is better predicted by the current environmental complexity of the region than within the subtropical populations. The concordant response of multiple co-occurring populations is consistent with spatial climatic variability as a major process driving population differentiation. Our results provide evidence for how a narrow latitudinal gradient can shape microevolutionary processes and contribute to broader scale biodiversity patterns.
热带山脉的生物多样性比温带山脉多，这种差异通常与纬度气候梯度有关。然而，由于热带和温带生物群之间的进化距离，区分纬度的影响与物种历史和特征的背景效应具有挑战性。在这里，我们测试了微进化过程是否与巴西大西洋南部森林 21 种山地鸟类在一个急剧的纬度转变过程中的环境变化有关。我们发现，在热带山脉中，种群内的有效扩散能力较低，而基因组分化程度比亚热带种群更好地由该地区当前的环境复杂性来预测。多个共存种群的一致响应与作为驱动种群分化的主要过程的空间气候变异性是一致的。我们的研究结果为一个狭窄的纬度梯度如何塑造微进化过程并有助于更广泛的生物多样性模式提供了证据。
