(CNN) – Researchers said a fossil found in South Africa proves for the first time that mammal ancestors laid eggs.
The fossil belongs to a tightly-curled embryo of a Lystrosaurus.
Researchers said a fossil found in South Africa proves for the first time that mammal ancestors laid eggs.(Benoit et al via CNN Newsource)
The Lystrosaurus is a mammal ancestor that survived an extinction event more than 250 million years ago known as the “Great Dying.”
Researchers found the Lystrosaurus embryo’s jaws were not completely fused.
That trait is only found in the embryos of modern birds and turtles. The study’s lead author said it proves the Lystrosaurus embryo had been inside an egg when it died.
The study’s findings were published Thursday in the journal PLOS ONE.
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