Les duplications de génome ont aidé les plantes à fleurs à survivre aux extinctions de masse

8 mai 2026

Rapporté par l'IA

Des copies supplémentaires de matériel génétique semblent avoir favorisé la survie des plantes à fleurs lors des crises environnementales majeures qu'a connues la Terre, y compris l'événement qui a anéanti les dinosaures.

Une étude portant sur 470 espèces d'angiospermes a révélé 132 duplications de génome anciennes, regroupées autour de neuf périodes de bouleversements survenues entre 108 millions et 14 millions d'années. Celles-ci incluent des changements climatiques, des variations des niveaux d'oxygène et des extinctions de masse, comme l'impact d'astéroïde survenu il y a 66 millions d'années à la fin du Crétacé.

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lundi 04 mai 2026 22h19