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神秘恐龙前体弥补翼龙起源空白
2020-12-11 17:02

英国伯明翰大学Martín D. Ezcurra研究组合作取得最新进展。他们发现了神秘的恐龙前体,并弥补了翼龙起源的空白。该研究于2020年12月9日发表于《自然》杂志。

利用最新发现的保存完好碎片颅骨(下颌,颅骨顶和脑箱)的微计算机断层扫描以及可靠的相关颅后骨,他们证明了紫薇龙(一组壮大的、非暴力的恐龙前体)是翼龙的姊妹群,在整个骨骼上有许多类似突触形态。这一发现大大缩短了最古老的翼龙与其近亲之间的时间和形态学差距,同时也加强了翼龙属于禽类鸟类的证据。

与翼龙增强的感觉能力有关的神经解剖学特征已经存在于紫薇龙中,这表明这些特征在飞行之前就已经进化了。他们的证据阐明了翼龙身体计划的组装的第一步,其对空中空间的征服代表了脊椎动物进化中的显著形态功能创新。

据了解,翼龙是第一个进化为动力飞行的脊椎动物,并且是中生代(大约在252-66百万年前)陆地生态系统中的主要进化辐射之一,但是自19世纪以来,它们的起源一直是古生物学中一个尚未解决的谜团。这些飞行的爬行动物被认为是各种爬行动物进化枝的近亲,包括恐龙的亲属,但这些形态和最古老的形态之间仍然存在较大的形态学鸿沟,上三叠纪系列翼龙仍然不清楚。

附:英文原文

Title: Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria

Author: Martn D. Ezcurra, Sterling J. Nesbitt, Mario Bronzati, Fabio Marco Dalla Vecchia, Federico L. Agnolin, Roger B. J. Benson, Federico Brissn Egli, Sergio F. Cabreira, Serjoscha W. Evers, Adriel R. Gentil, Randall B. Irmis, Agustn G. Martinelli, Fernando E. Novas, Lcio Roberto da Silva, Nathan D. Smith, Michelle R. Stocker, Alan H. Turner, Max C. Langer

Issue&Volume: 2020-12-09

Abstract: Pterosaurs were the first vertebrates to evolve powered flight1 and comprised one of the main evolutionary radiations in terrestrial ecosystems of the Mesozoic era (approximately 252–66 million years ago), but their origin has remained an unresolved enigma in palaeontology since the nineteenth century2,3,4. These flying reptiles have been hypothesized to be the close relatives of a wide variety of reptilian clades, including dinosaur relatives2,3,4,5,6,7,8, and there is still a major morphological gap between those forms and the oldest, unambiguous pterosaurs from the Upper Triassic series. Here, using recent discoveries of well-preserved cranial remains, microcomputed tomography scans of fragile skull bones (jaws, skull roofs and braincases) and reliably associated postcrania, we demonstrate that lagerpetids—a group of cursorial, non-volant dinosaur precursors—are the sister group of pterosaurs, sharing numerous synapomorphies across the entire skeleton. This finding substantially shortens the temporal and morphological gap between the oldest pterosaurs and their closest relatives and simultaneously strengthens the evidence that pterosaurs belong to the avian line of archosaurs. Neuroanatomical features related to the enhanced sensory abilities of pterosaurs9 are already present in lagerpetids, which indicates that these features evolved before flight. Our evidence illuminates the first steps of the assembly of the pterosaur body plan, whose conquest of aerial space represents a remarkable morphofunctional innovation in vertebrate evolution.

DOI: 10.1038/s41586-020-3011-4

Source: https://www.nature.com/articles/s41586-020-3011-4

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:43.07
官方网址:http://www.nature.com/
投稿链接:http://www.nature.com/authors/submit_manuscript.html


本期文章:《自然》:Online/在线发表

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