#lystrosaurus

Scientists have their first proof that the ancestors of some mammals laid eggs, thanks to a 250-million-year-old fossil embryo discovered in South Africa in 2008. The specimen, described this week in PLOS One, belongs to a piglike animal with tusks and a beak called Lystrosaurus that famously and mysteriously survived the Great Dying, one of Earth’s worst extinction events. The embryo’s curved position and the incomplete development of its jaw, pelvis, and ribs hint that it was in an egg when it died (artist’s rendition above). The fossil could shed light on how Lystrosaurus survived the high temperatures of the extinction event, as the large size of the eggs would have prevented the water loss that comparable species faced, CNN reports. The find may also help researchers learn why and when lactation developed in mammals, providing evidence it initially evolved to allow mothers to keep their eggs moist.

Lystrosaurus

Lystrosaurus (Greek meaning “shovel reptile”) was a herbivore dicynodont that lived from the Lopingian (late Permian) to Early Triassic. Its fossils are known from South Africa, India, Russia, China and Antarctica. Lystrosaurus survived the Permian-Triassic extinction event, and went onto thrive in the early Triassic, at one point making up 95% of all terrestrial Vertebrates.

Lystrosaurus is notable for dominating southern Pangaea for millions of years during the Early Triassic. At least one unidentified species of this genus survived the end-Permian mass extinction and, in the absence of predators and herbivorous competitors, went on to thrive and re-radiate into a number of species within the genus, becoming the most common group of terrestrial vertebrates during the Early Triassic; for a while, 95% of land vertebrates were Lystrosaurus. This is the only time that a single species or genus of land animal dominated the Earth to such a degree. A few other Permian therapsid genera also survived the mass extinction and appear in Triassic rocks—the therocephalians Tetracynodon, Moschorhinus and Ictidosuchoides—but do not appear to have been abundant in the Triassic; complete ecological recovery took 30 million years, spanning the Early and Middle Triassic…

Text via: Wikipedia

I'm Liam Elward, digital paleoartist looking for work in scientific illustration & paleontology. Email for inquiries/commissions of any & all extinct or living organisms!

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