英国伦敦帝国理工学院Martin D. Brazeau团队近期取得重要工作进展，他们研究发现了脊椎动物胸带咽起源的化石证据。相关研究成果2023年11月1日在线发表于《自然》杂志上。
据介绍，脊椎动物成对附肢的起源是演化新颖性研究和争论最多的例子之一。成对的附肢被广泛认为是关键的创新，为受控游泳和鳃通气提供了新的机会，也是最终从水里过渡到陆地的先决条件。过去150年的争论是由两种有争议的理论形成的：“鳍褶假说”和“鳃弓假说”。后者提出鳍和带是由祖先的鳃弓进化而来的。尽管对动物发育的研究重新激发了人们对这一想法的兴趣，但目前没有化石证据的支持。
研究人员提出了脊椎动物肩带咽部基础的古生物学支持。研究人员使用计算机断层扫描来揭示西伯利亚早泥盆世斑尾鱼（Kolymaspis sibirica）的脑壳细节，这表明肩部有咽部成分。研究人员将这些发现与新的肩胛骨和无颌外组的比较解剖相结合，将肩带的起源放在第六鳃弓上。这些发现为理解胸带的起源提供了一个新的框架。
总之，这一证据阐明了无颌鱼类假定的头-躯干界面的位置，并解释了颌类鱼类鳃弓数量的限制。这一结果复兴了原鳍假说的一个关键方面，并有助于将其与腹外侧鳍折叠模型相协调。
附：英文原文
Title: Fossil evidence for a pharyngeal origin of the vertebrate pectoral girdle
Author: Brazeau, Martin D., Castiello, Marco, El Fassi El Fehri, Amin, Hamilton, Louis, Ivanov, Alexander O., Johanson, Zerina, Friedman, Matt
Issue&Volume: 2023-11-01
Abstract: The origin of vertebrate paired appendages is one of the most investigated and debated examples of evolutionary novelty1,2,3,4,5,6,7. Paired appendages are widely considered as key innovations that enabled new opportunities for controlled swimming and gill ventilation and were prerequisites for the eventual transition from water to land. The past 150 years of debate8,9,10 has been shaped by two contentious theories4,5: the ventrolateral fin-fold hypothesis9,10 and the archipterygium hypothesis8. The latter proposes that fins and girdles evolved from an ancestral gill arch. Although studies in animal development have revived interest in this idea11,12,13, it is apparently unsupported by fossil evidence. Here we present palaeontological support for a pharyngeal basis for the vertebrate shoulder girdle. We use computed tomography scanning to reveal details of the braincase of Kolymaspis sibirica14, an Early Devonian placoderm fish from Siberia, that suggests a pharyngeal component of the shoulder. We combine these findings with refreshed comparative anatomy of placoderms and jawless outgroups to place the origin of the shoulder girdle on the sixth branchial arch. These findings provide a novel framework for understanding the origin of the pectoral girdle. Our evidence clarifies the location of the presumptive head–trunk interface in jawless fishes and explains the constraint on branchial arch number in gnathostomes15. The results revive a key aspect of the archipterygium hypothesis and help reconcile it with the ventrolateral fin-fold model.
DOI: 10.1038/s41586-023-06702-4
Source: https://www.nature.com/articles/s41586-023-06702-4
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
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
