Evolutionary Revolution: 236-Million-Year-Old Fossil from Argentina Challenges Mammal Origins
A study published in Frontiers in Mammal Science reveals that Chiniquodon theotonicus, a mammal ancestor that lived in Argentina's La Rioja province 236 million years ago, might have given birth to live young. This discovery pushes back the appearance of viviparity in the mammalian lineage by 90 to 95 million years.