Paleontologists in China's Sichuan Basin have unearthed the exceptionally well-preserved remains of a 155-million-year-old semi-aquatic mammaliamorph. The fossil, which includes impressions of thick, paddle-like limbs and dense fur, suggests that mammalian ancestors adapted to aquatic environments tens of millions of years earlier than previously believed.
This new species, named Sichuanhydrotes sinensis, features a specialized jaw structure for hunting small fish and aquatic insects. Researchers believe this finding challenges the long-held theory that Jurassic mammals were strictly land-dwelling insectivores, revealing a surprising diversity of lifestyles in early mammalian lineages.