2022.08.04

How Mammals Prevailed

They scurried in the shadows of dinosaurs for millions of years until a killer asteroid created a new world of evolutionary opportunity

EARLY PLACENTAL MAMMAL Ectoconus gave birth to live, welldeveloped young. Illustration by Beth Zaiken

EARLY PLACENTAL MAMMAL Ectoconus gave birth to live, welldeveloped young. Illustration by Beth Zaiken

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