Studie löser mysteriet om hur kräldjurs benpansar utvecklades

22 maj 2026

Rapporterad av AI

En ny evolutionsanalys har visat att hudben hos kräldjur utvecklades oberoende av varandra i flera olika ödlegrupper snarare än från en gemensam förfader. Forskare har spårat egenskapen över 320 miljoner år med hjälp av fossil och beräkningsmetoder. Australiska goannor utmärker sig genom att ha förlorat pansaret för att sedan återfå det miljontals år senare.

Studien, som publicerats i Biological Journal of the Linnean Society, kombinerade data från 643 levande och utdöda arter. Den fastställde att de flesta ödlor först utvecklade osteodermer för mer än 100 miljoner år sedan under sen jura och tidig krita. Dessa beniga strukturer bidrog troligen till deras överlevnad i ett föränderligt klimat och bland de rovdjur som fanns under dinosauriernas tid, såsom Brachiosaurus och Stegosaurus.

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