Il y a plus de 550 millions d’années, les premiers animaux peuplaient déjà les océans terrestres sous des formes très différentes de celles d’aujourd’hui. Longtemps dominés par des organismes fixés au fond marin et se reproduisant probablement par clonage, ces écosystèmes auraient connu une...
Fossils from some of the oldest-known animals on Earth, dating from 574 million years ago (Ediacaran period), suggest that cloning, not competition, dominated the Ediacaran seas, slowing evolution until environmental stress helped drive the rise of sexual reproduction and a burst of biodiversity.
Outside experts found that two studies cited in a federal case on medication abortion had serious design problems and that their authors had undisclosed conflicts of interest
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