Jonah Choiniere, a paleobiologist at the University of the Witwatersrand, Johannesburg, was boating around the world’s largest artificial lake in 2018 when he and his team found the first known fossils of Musankwa sanyatiensis — an ancestor of the sauropod dinosaurs from around 210 million years ago.
Part of a flood of similar discoveries from the past decade or so, the fossils hint at how the four-legged sauropods developed from the two-legged sauropodomorphs that preceded them.
“We knew right away this is not something we’d ever seen before,” Choiniere says. In fact, the fossils fill a gap in the early evolution of the sauropods — the long-legged, long-necked herbivores that would eventually become the world’s largest dinosaurs.
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