Coimbra Raphael Teodoro Franciscani, Miranda Flávia Regina, Lara Camila Clozato, Schetino Marco Antônio Alves, Santos Fabrício Rodrigues Dos
Laboratório de Biodiversidade e Evolução Molecular, Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Genet Mol Biol. 2017 Jan-Mar;40(1):40-49. doi: 10.1590/1678-4685-GMB-2016-0040. Epub 2017 Feb 13.
Cyclopes didactylus, commonly called silky anteater, is the smallest and least studied of the anteaters. It is an arboreal species occurring in rainforests, ranging from southern Mexico to Central and South America, with an apparently disjoint distribution between Amazon and Atlantic rainforests in Brazil. Although seven subspecies are recognized, little is known about its geographical variation. Thus, to evaluate the population dynamics and evolutionary history of the South American silky anteater, we analyzed 1542 bp sequences of the mitochondrial control region (CR), COI and Cyt-b genes of 32 individuals. Haplotype network, AMOVA and molecular dating analyses were performed and identified seven geographic clusters. The split of lineages separating Cyclopedidae (Cyclopes) and Myrmecophagidae (Myrmecophaga and Tamandua genera) was estimated around 41 million years ago (mya), and the intraspecific lineage diversification of C. didactylus began in the Miocene around 13.5 mya, likely in southwestern Amazonia. Tectonic and climatic events that took place in South America during the Tertiary and Quaternary seem to have influenced the evolutionary history of the species at different levels. This is the first study to investigate the population dynamics and phylogeography of the silky anteater, which contributes to a better comprehension of the biogeography of South America.
中美小食蚁兽,通常被称为丝食蚁兽,是食蚁兽中体型最小且研究最少的。它是一种树栖物种,分布于从墨西哥南部到中美洲和南美洲的雨林中,在巴西的亚马逊雨林和大西洋雨林之间呈现出明显不连续的分布。尽管已识别出七个亚种,但对其地理变异了解甚少。因此,为了评估南美丝食蚁兽的种群动态和进化历史,我们分析了32个个体的线粒体控制区(CR)、细胞色素氧化酶亚基I(COI)和细胞色素b(Cyt-b)基因的1542 bp序列。进行了单倍型网络分析、分子方差分析(AMOVA)和分子定年分析,确定了七个地理集群。Cyclopedidae科(中美小食蚁兽属)和Myrmecophagidae科(大食蚁兽属和小食蚁兽属)的谱系分化估计发生在约4100万年前,而中美小食蚁兽的种内谱系多样化始于中新世约1350万年前,可能发生在亚马逊西南部。第三纪和第四纪期间在南美洲发生的构造和气候事件似乎在不同层面上影响了该物种的进化历史。这是第一项研究丝食蚁兽种群动态和系统地理学的研究,有助于更好地理解南美洲的生物地理学。