Researchers Confirm Mammal Ancestors Laid Eggs, Shedding Light on Evolutionary Traits
A groundbreaking study has confirmed that mammal ancestors, specifically the Lystrosaurus, laid eggs. This discovery was made through the analysis of a 250-million-year-old fossil found in South Africa. The fossil, belonging to a Lystrosaurus embryo, provides the first concrete evidence that these ancient creatures reproduced by laying eggs. The study, published in the journal PLOS One, utilized high-resolution computer tomography and synchrotron X-rays to reveal that the embryo's jaws were not fully fused, a trait seen in modern bird and turtle embryos. This finding suggests that the Lystrosaurus embryo was inside an egg when it died. The research also offers insights into why Lystrosaurus survived the 'Great Dying,' a mass extinction event 252 million years ago, by suggesting that their leathery eggs were better suited to dry environments. 
