252百万年前に発生したペルム紀末絶滅は海洋種の80%以上を絶滅させたが、多くの海洋生態系は頂点捕食者が生存する複雑な構造を維持した。世界7カ所の海洋地点を対象とした新たな研究は、深刻な損失にもかかわらず5つの生態系が少なくとも4つの栄養段階を保持していたことを明らかにした。これは、生態系の回復力が独自の種構成に依存することを示唆し、現代の気候脅威への示唆を提供する。
ペルム紀末絶滅は約252百万年前に発生し、記録上最も深刻な大量絶滅として知られる。現在シベリアにあたる地域での大規模火山噴火が引き金となり、地球温暖化、海洋の脱酸素化、その他の環境ストレスを引き起こし、海洋種の80%以上を絶滅させた。三葉虫やユーリプテリッド（海サソリ）を含むグループが完全に姿を消し、他のグループも大きな打撃を受けた。回復期には、恐竜や魚竜などの新たな系統が出現した。
Researchers at the Okinawa Institute of Science and Technology have revealed how squid and cuttlefish survived the Cretaceous-Paleogene mass extinction by retreating to oxygen-rich deep-sea refuges. Their analysis of newly sequenced genomes shows these cephalopods originated in the deep ocean over 100 million years ago, followed by rapid diversification into shallow waters. The findings, published in Nature Ecology & Evolution, provide the first comprehensive evolutionary tree for decapodiform cephalopods.
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Researchers have uncovered evidence that octopuses from the Late Cretaceous period, around 100 million years ago, grew to lengths of nearly 20 meters and hunted as top predators. The findings, based on well-preserved fossil jaws from Japan and Vancouver Island, challenge previous views of early octopus evolution. Professor Yasuhiro Iba of Hokkaido University led the study, published in Science on April 23.
Newly examined fossils indicate that the earliest four-limbed vertebrates developed directly into adults without a larval phase featuring external gills.
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Scientists suggest that asteroid impacts created hot, chemical-rich environments that could have kick-started life on Earth. A new review led by recent Rutgers graduate Shea Cinquemani highlights impact-generated hydrothermal systems as potential cradles for life's building blocks. These systems may have persisted for thousands of years, providing ideal conditions for early biology.