Triassic stem caecilian supports dissorophoid origin of living amphibians.
Triassic stem caecilian supports dissorophoid origin of living amphibians.
复制标题
DOI：
10.1038/s41586-022-05646-5
复制
发表时间：
2023-03
期刊：
影响因子：
64.8
通讯作者：
Stocker, Michelle R. R.
中科院分区：
文献类型：
--
作者：
Kligman, Ben T. T.;Gee, Bryan M. M.;Marsh, Adam D. D.;Nesbitt, Sterling J. J.;Smith, Matthew E. E.;Parker, William G. G.;Stocker, Michelle R. R.
活着的两栖动物包括青蛙和火蜥蜴(蝙蝠纲)和无肢的蠕虫状鞭毛虫(Gymnophiona)。估计的古生代裸体动物-白背飞虫的分子差异表明，在三叠纪最早的化石出现之前，树冠利桑鱼的记录存在重大差距。最近的研究发现，在分离的脊椎动物中存在一个单系的蝙蝠纲动物，但由于缺乏前侏罗纪时期的盲肠动物化石，它们与蝙蝠纲动物的关系以及与古生代四足动物的亲缘关系存在争议。在这里，我们报道了地质上最古老的茎盲肠动物--一种来自美国亚利桑那州晚三叠世冠上的利塞米亚人--将盲肠动物的记录延长了约3500万年。这些化石阐明了早期盲肠动物形态和功能进化的节奏和模式，显示了与化石相关的肌肉骨骼特征的延迟获得，包括双颌闭合机制、减少的眼眶和触须器官。这些化石的来源表明，盲肠动物起源于盘古赤道，这意味着活的盲肠生物地理反映了盲肠功能和生理的保守方面，以及板块构造驱动的更替模式。这些化石揭示了食虫目动物独有的特征以及与蝙蝠类和类双脊椎动物共有的特征，提供了新的令人信服的证据，支持双脊椎动物中生活的两栖动物的单一来源。对已知最古老的盲肠动物化石的分析提供了对盲肠动物的起源以及形态和功能进化的洞察。
Living amphibians (Lissamphibia) include frogs and salamanders (Batrachia) and the limbless worm-like caecilians (Gymnophiona). The estimated Palaeozoic era gymnophionan–batrachian molecular divergence suggests a major gap in the record of crown lissamphibians prior to their earliest fossil occurrences in the Triassic period. Recent studies find a monophyletic Batrachia within dissorophoid temnospondyls, but the absence of pre-Jurassic period caecilian fossils has made their relationships to batrachians and affinities to Palaeozoic tetrapods controversial. Here we report the geologically oldest stem caecilian—a crown lissamphibian from the Late Triassic epoch of Arizona, USA—extending the caecilian record by around 35 million years. These fossils illuminate the tempo and mode of early caecilian morphological and functional evolution, demonstrating a delayed acquisition of musculoskeletal features associated with fossoriality in living caecilians, including the dual jaw closure mechanism, reduced orbits and the tentacular organ. The provenance of these fossils suggests a Pangaean equatorial origin for caecilians, implying that living caecilian biogeography reflects conserved aspects of caecilian function and physiology, in combination with vicariance patterns driven by plate tectonics. These fossils reveal a combination of features that is unique to caecilians alongside features that are shared with batrachian and dissorophoid temnospondyls, providing new and compelling evidence supporting a single origin of living amphibians within dissorophoid temnospondyls. Analysis of fossils of the oldest known caecilian provide insights into the origin and morphological and functional evolution of caecilians.
登录
查看更多内容
影响因子：
1.4
作者：
Kobayashi, Y;Azuma, Y
通讯作者：
Azuma, Y
影响因子：
3.6
作者：
Goloboff, Pablo A.;Catalano, Santiago A.
通讯作者：
Catalano, Santiago A.
影响因子：
4.6
作者：
Jared, Carlos;Mailho-Fontana, Pedro Luiz;Antoniazzi, Marta Maria
通讯作者：
Antoniazzi, Marta Maria
DOI：
10.3099/0027-4100(2007)158
发表时间：
2007-08-20
期刊：
Bulletin of the Museum of Comparative Zoology
影响因子：
--
作者：
Jenkins, Farish A., Jr.;Walsh, Denis M.;Carroll, Robert L.
通讯作者：
Carroll, Robert L.
DOI：
10.1111/j.1096-3642.2008.00444.x
发表时间：
2009-02-01
影响因子：
2.8
作者：
Damiani, Ross;Schoch, Rainer R.;Gastou, Stephanie
通讯作者：
Gastou, Stephanie