Story thread · 2 reports / 2 sources

When Did Animals Start Giving Birth to Live Young? This 236-Million-Year-Old Fossil Might Rewrite Mammals' Evolutionary History

smithsonianmag.com · 2hShare

A bone feature found in a mammal ancestor hints that the creature was relatively large as a newborn, more in line with the size of a creature birthed live than hatched from an egg. Still, it provides only indirect evidence

First report: ‘Very weird’: 236-million-year-old fossil proves mammals stopped laying eggs earlier than we thought — nypost.com, 1d