An ancient marine reptile named Hupehsuchus nanchangensis,which lived around 247 to 249 million years ago during the early Triassic Period, is believed to have used a feeding technique similar to modern filter-feeding whales.Fossils of this reptile were first discovered in China in 1972,but due to poorly preserved skulls, its feeding behavior and lifestyle were not well understood.

Recent discoveries of two well-preserved fossils from China’s Jialingjiang Formation shed new light on the reptile’s anatomy and feeding strategy.The fossils included a nearly complete skeleton and a large portion of another specimen, providing researchers with a better understanding of the reptile’s features.The newly studied fossils revealed that Hupehsuchus had a toothless snout and a loosely connected lower jaw,allowing its mouth to expand. This flexibility of the mouth is akin to how modern whales engage in filter feeding.

By examining the skull of Hupehsuchus and comparing it to 130 modern aquatic animal skulls, including various species of whales, seals, crocodilians, birds, and more, researchers found that the reptile had similarities with baleen whales.Baleen whales use a filter-feeding technique to consume large quantities of plankton or krill by sifting water through plates of baleen in their mouths. Although there’s no direct evidence of baleen in the Hupehsuchus skull,researchers observed grooves in the roof of the mouth that could have aided in filter feeding, similar to the structures seen in baleen whales.

This discovery challenges the existing understanding of ancient reptiles’feeding behaviors and shows a case of convergent evolution, where similar traits evolve independently in different species.Hupehsuchus likely expanded its throat while swimming to gulp down water and filter out shrimplike prey from the oceans.This feeding strategy is thought to have evolved relatively quickly,within about 5 million years,in marine reptiles much earlier than the evolution of filter feeding in modern whales.

The Hupehsuchus reptiles lived in a time of rapid recovery and repopulation of the oceans after a massive mass extinction event.The study of these ancient marine reptiles provides valuable insights into the evolution of marine ecosystems and the adaptations that emerged during this transformative period in Earth’s history.