寒武纪早期最早的带虹吸管的头足类动物
寒武纪早期最早的带虹吸管的头足类动物
作者： 小柯机器人 发布时间：2026/7/30 17:41:31
本期文章：《自然》：Online/在线发表
长安大学温汉捷小组近日取得一项新成果。经过不懈努力，他们研制了寒武纪早期最早的带虹吸管的头足类动物。这一研究成果发表在2026年7月29日出版的国际学术期刊《自然》上。
在这里，研究小组报道陕西始角石（Eoceras shaanxiense gen. et sp. nov.），，一种产自华南水井沱组（寒武纪第三期）的毫米级头足类化石，具有直锥形壳。其壳体内部发育多个隔膜，以及一条位于边缘的、由微小管道连接隔膜的分节管，这表明在生长过程中，软体向壳口方向迁移以形成连续房室，同时通过该管与先前的房室保持联系。综合这些特征，研究将陕西始角石中的这一分节管鉴定为原始头足类体管的候选结构，从而将干群头足类的已知分布范围追溯至寒武纪早期，并揭示了用于浮力调节的分室气壳在演化组装过程中的早期阶段。
据悉，现代头足类动物在软体动物中是独一无二的，因为它们的祖先有一个腔室，充满气体和液体的外壳，其内部隔膜由虹吸管穿透。与喷射推进相结合，虹吸管使头足类动物能够通过长期调节其浮力来从事一种主要是掠夺性的生活方式。这一关键创新的起源仍然未知，因为已知最早的头足类动物——寒武纪晚期的Plectronoceras cambria2型头足类动物，与分子钟估计的寒武纪早期与其他软体动物的谱系分化之间存在重大差距。
附：英文原文
Title: Earliest siphuncle-bearing cephalopod from the early Cambrian
Author: Song, Zuchen, Pan, Bing, Guo, Junfeng, Vinther, Jakob, Li, Guoxiang, Han, Jian, Van Iten, Heyo, Zhao, Xiaofang, Pei, Xianzhi, Peng, Jiaxin, Qiang, Yaqin, Zhang, Boyao, Wen, Hanjie
Issue&Volume: 2026-07-29
Abstract: Modern cephalopods are unique among molluscs in ancestrally possessing a chambered, gas- and fluid-filled shell, the internal septa of which are penetrated by a siphuncle. Combined with jet propulsion, the siphuncle enables cephalopods to engage in a nektonic and mostly predatory lifestyle through long-term regulation of their bouyancy1. The origin of this key innovation remains unknown, as major gaps exist between the earliest accepted cephalopod, Plectronoceras cambria2 from the late Cambrian era, and molecular clock estimates placing the divergence of the lineage from other molluscs in the early Cambrian3,4. Here we report Eoceras shaanxiense gen. et sp. nov., a millimetre-sized cephalopod with an orthoconic shell from the Shuijingtuo Formation (Cambrian Stage 3) of South China. Internally, the shell exhibits multiple septa along with a peripherally situated segmented tube that appears to bridge the septa through minute canals, indicating that the soft body migrated aperturally to form successive chambers during growth while maintaining contact with earlier chambers via the tube. Collectively, these features identify the segmented tube in E. shaanxiense gen. et sp. nov. as a candidate primordial cephalopod siphuncle, thus extending the known range of stem cephalopods back to the early Cambrian and revealing the early stages in the evolutionary assembly of a chambered phragmocone employed in buoyancy regulation.
DOI: 10.1038/s41586-026-10868-y
Source: https://www.nature.com/articles/s41586-026-10868-y