"Archosaur Discovery Illuminates Dinosaur Armor Evolution"

TL;DR
Researchers have discovered a new species of archosaur, Mambachiton fiandohana, which had bony plates along its backbone, indicating that armor was an evolutionary trait that appeared and disappeared multiple times in the lineage of dinosaurs and pterosaurs. The fossil, approximately 235 million years old, was found in Madagascar and is the earliest known member of the bird-line archosaur evolution. This finding sheds light on the evolution of armor in dinosaurs and pterosaurs, showing that it was lost and re-evolved independently in different lineages.
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