BERLIN – Giant plant-eating creatures with mouths like beaks and reptile features may explore the Earth during the late Triassic period more than 200 million years ago, say scientists. In a paper published Thursday by the journal Science, Polish researchers claim their findings overturned the notion that the only giant plant eater at the time was dinosaurs.
An elephant-sized creature, known as Lisowicia bojani after a village in southern Poland where remains were found, belonging to the same evolutionary branch as mammals.
Similar fossils of so-called dicynodonts have been found elsewhere, but they originate from the previous period, before a series of natural disasters destroyed most species on Earth.
"We used to think that after the Permian extinction ended, their mammals and relatives retreated into the shadows while dinosaurs rose and grew into large sizes," said Grzegorz Niedzwiedzki, a paleontologist at Uppsala University in Sweden who co-wrote the paper.
The discovery of giant dicynodonts that lived at the same time as sauropods – a branch of the dinosaur family that later produced the iconic long-necked diplomacy – showing environmental factors in the late Triassic period might have encouraged the evolution of gigantism, the researchers said.
Christian Kammerer, a specialist who was synodont at the North Carolina Museum of Natural Sciences was not involved in the discovery, saying that the size of Lisowicia was "shocking."
"Big dicynodonts have been known before in Permian and Trias, but never on this scale," he said.
Kammerer said that when dicynodonts and dinosaurs existed at the same time, there was no evidence that they lived in the same habitat. He also questioned the conclusions of the study of Lisowicia's posture.
"However, overall I think this is a very interesting and important paper, and shows us that there is still much left to be learned about the relatives of the early mammals in the Triassic," Kammerer said.
Last year, a study proclaimed aheavyweight champion of all dinosaurs – weighing 76 tons, giant plant-eating is as heavy as a spacecraft.
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