Mass extinction triggered the early radiations of jawed vertebrates and their jawless relatives (gnathostomes).
大灭绝触发有颌脊椎动物及其无颌近亲的早期辐射

Authors / 作者: Hagiwara W, Sallan L.
Journal / 期刊: Science advances
Year / 年份: 2026
DOI: 10.1126/sciadv.aeb2297
Publisher / 出版社: https://www.science.org/doi/10.1126/sciadv.aeb2297
Abstract source / 摘要来源: https://europepmc.org/article/MED/41512057

Author abstract / 作者原文摘要
Most vertebrate lineages are first recorded from the mid-Paleozoic, well after their Cambrian origin and Ordovician invertebrate biodiversification events. This delay has been poorly understood and is usually attributed to sampling and long ghost lineages. We analyzed newly compiled databases of Paleozoic vertebrate occurrences, biogeography, and ecosystems, revealing that the Late Ordovician Mass Extinction (~445 to 443 million years ago) triggered parallel, endemic radiations of jawed and related jawless vertebrates (gnathostomes) in isolated refugia. Postextinction ecosystems hosted the first definitive appearances of most major vertebrate lineages of the Paleozoic "Age of Fishes" (and today), following the loss of ubiquitous stem-cyclostome conodonts, nascent faunas of other gnathostomes, and pelagic invertebrates. Turnover and recovery patterns matched those following climatically similar events like the end-Devonian mass extinction, including a postextinction "gap" with low biodiversity. The prolonged Silurian recovery, and the challenges of oceanic dispersal, likely further delayed the dominance of jawed gnathostomes for millions of years after the first fossil jaws.

Summary basis / 解读依据
摘要解读依据已查看的索引作者摘要；如已保存全文，可用于进一步阅读。
Summary based on the inspected indexed author abstract; archived full text, when available, is provided for further reading.

Key findings / 主要发现
新整理的古生代脊椎动物出现记录、生物地理与生态系统数据库显示，晚奥陶世大灭绝后，有颌类及相关无颌类在隔离避难所中发生平行的地方性辐射，恢复过程中包含较长的低多样性阶段。
New databases of Palaeozoic vertebrate occurrences, biogeography and ecosystems indicate parallel endemic radiations of jawed and related jawless vertebrates after the Late Ordovician mass extinction. Recovery took place in isolated refugia and included a prolonged low-diversity interval.

Conclusions / 结论
大灭绝及其后的地理隔离参与塑造早期脊椎动物多样化；生态恢复与扩散限制可能解释了有颌类在颌首次出现很久之后才取得优势。
Mass extinction and subsequent geographical isolation helped structure early vertebrate diversification. Ecological recovery and dispersal constraints may explain why jawed vertebrates became dominant long after jaws first appeared.

Relevance / 关联说明
研究早期无颌与有颌脊椎动物的辐射，并非多鳃鱼的直接描述。
Analysis concerns early jawless and jawed vertebrate radiations, not a direct description of Polybranchiaspis.