Cisneros Juan C, Marsicano Claudia, Angielczyk Kenneth D, Smith Roger M H, Richter Martha, Fröbisch Jörg, Kammerer Christian F, Sadleir Rudyard W
Centro de Ciências da Natureza, Universidade Federal do Piauí, 64049-550 Teresina, Brazil.
Programa de Pós-Graduação em Geociências, Departamento de Geologia, Universidade Federal de Pernambuco, 50740-533 Recife, Brazil.
Nat Commun. 2015 Nov 5;6:8676. doi: 10.1038/ncomms9676.
Terrestrial vertebrates are first known to colonize high-latitude regions during the middle Permian (Guadalupian) about 270 million years ago, following the Pennsylvanian Gondwanan continental glaciation. However, despite over 150 years of study in these areas, the biogeographic origins of these rich communities of land-dwelling vertebrates remain obscure. Here we report on a new early Permian continental tetrapod fauna from South America in tropical Western Gondwana that sheds new light on patterns of tetrapod distribution. Northeastern Brazil hosted an extensive lacustrine system inhabited by a unique community of temnospondyl amphibians and reptiles that considerably expand the known temporal and geographic ranges of key subgroups. Our findings demonstrate that tetrapod groups common in later Permian and Triassic temperate communities were already present in tropical Gondwana by the early Permian (Cisuralian). This new fauna constitutes a new biogeographic province with North American affinities and clearly demonstrates that tetrapod dispersal into Gondwana was already underway at the beginning of the Permian.
陆生脊椎动物首次被认为是在大约2.7亿年前的中二叠世（瓜德鲁普世），即在宾夕法尼亚纪冈瓦纳大陆冰川作用之后，开始在高纬度地区栖息。然而，尽管在这些地区已经研究了150多年，但这些丰富的陆地脊椎动物群落的生物地理起源仍然不明。在此，我们报告了来自热带西冈瓦纳地区南美洲的一个新的早二叠世大陆四足动物群，该动物群为四足动物的分布模式提供了新的线索。巴西东北部曾有一个广泛的湖泊系统，居住着一个独特的离片椎类两栖动物和爬行动物群落，这大大扩展了关键亚群已知的时间和地理范围。我们的研究结果表明，在二叠纪晚期和三叠纪温带群落中常见的四足动物类群在早二叠世（ Cisuralian ）时就已出现在热带冈瓦纳地区。这个新动物群构成了一个具有北美亲缘关系的新生物地理省份，并清楚地表明在二叠纪开始时，四足动物向冈瓦纳的扩散就已经开始。
