ICB-BIOMACRO-Lab-Laboratório de Biogeografia da Conservação e Macroecologia, Universidade Federal do Pará, Belém, PA, Brazil.
Sociedade para a Conservação da Aves do Brasil, Rua Vereador José Cícero Epifânio, Lagoa dos Gatos, PE, Brazil.
PLoS One. 2020 Oct 13;15(10):e0238729. doi: 10.1371/journal.pone.0238729. eCollection 2020.
The Amazonian and Atlantic Forest share several organisms that are currently isolated but were continuously distributed during the Quaternary period. As both biomes are under different climatic regimes, paleoclimatic events may have modulated species' niches due to a lack of gene flow and imposing divergent selection pressure. Here, we assessed patterns of ecological niche overlap in 37 species of birds with disjunct ranges between the Amazonian and Brazilian Atlantic Forests. We performed niche overlap analysis and ecological niche modeling using four machine-learning algorithms to evaluate whether species' ecological niches evolved or remained conserved after the past South American biogeographic events. We found a low niche overlap among the same species populations in the two biomes. However, niche similarity tests showed that, for half of the species, the overlap was higher than the ones generated by our null models. These results lead us to conclude that niche conservatism was not enough to avoid ecological differentiation among species even though detected in many species. In sum, our results support the role of climatic changes in late-Pleistocene-that isolated Amazon and the Atlantic Forest-as a driving force of ecological differences among the same species populations and potential mechanism of current diversification in both regions.
亚马逊和大西洋森林拥有一些目前处于隔离状态但在第四纪时期连续分布的共同生物。由于这两个生物群落在不同的气候条件下，古气候事件可能由于缺乏基因流而导致物种的生态位发生变化，并产生不同的选择压力。在这里，我们评估了 37 种鸟类在亚马逊和巴西大西洋森林之间的间断分布范围内的生态位重叠模式。我们使用四种机器学习算法进行了生态位重叠分析和生态位建模，以评估在过去的南美生物地理事件之后，物种的生态位是否进化或保持保守。我们发现两个生物群落在同一物种群体之间的生态位重叠度较低。然而，生态位相似性测试表明，对于一半的物种，重叠度高于我们的零模型生成的重叠度。这些结果使我们得出结论，尽管在许多物种中检测到了生态位保守性，但它不足以避免物种之间的生态分化。总之，我们的结果支持了晚更新世气候变化（将亚马逊和大西洋森林隔离）作为同一物种群体之间生态差异的驱动力的作用，以及当前这两个地区多样化的潜在机制。
