During the Triassic period (252-201 million years ago) mammalian reptiles called therapsids coexisted with the ancestors of dinosaurs, crocodiles, mammals, pterosaurs, turtles, frogs and lizards. One group of therapsids was dicynodonts. Researchers at Uppsala University in Sweden, along with colleagues in Poland, have found fossils from a new genus that is giant synodont. The new species Lisowicia bojani is explained in the journal Science.
The earth is around 4.5 billion years old and has gone through many geological periods and dramatic changes. During the Triassic period, around 252-201 million years ago, all land on Earth gathered and formed a giant continent called Pangea. During this time, the first dinosaurs appeared as well as ancestors of crocodiles, mammals, pterosaurs, turtles, frogs and lizards. Recently, scientists have been interested in other types of animals, therapsids. Therapsids are "mammal-like" reptiles and are the ancestors of mammals, including humans, found today. One group of therapsids is called dicynodonts. All species of dicynodonts are herbivores (plant eaters) and their sizes range from small diggers to large browsers. Most of them are also toothless. They survived the Permian mass extinction and became the dominant terrestrial herbivore in the Middle and Late Triassic. They were considered dead before dinosaurs became the dominant tetrapod form on land.
For the first time, researchers in the Evolution and Development research program at Uppsala University in collaboration with researchers at the Polish Academy of Sciences (Warsaw), have found fossils of new species copied in the Polish village of Lisowice. The species is named Lisowicia bojani after the village and German comparative anatomist named Ludwig Heinrich Bojanus who works in Vilnius and is known for making some important anatomical discoveries. The findings show that Lisowicia is about the size of a modern elephant, about 4.5 meters long, 2.6 meters long and weighing around 9 tons, which is 40 percent larger than previously recognized. Analysis of limb bones shows that they have rapid growth, such as mammals or dinosaurs. It lived during the Late Triassic, about 210-205 million years ago, about 10 million years later from previous findings from dicynodonts.
"Lisowicia's discovery changed our ideas about the latest history in the synodonts, a relative of the mammalian triasal. It also raises more questions about what really made them and dinosaurs so big," said Dr. Tomasz Sulej, Polish Academy of Sciences.
"Dicynodonts are exceptionally successful animals in the Middle and Final Triassic. Lisowicia is the youngest to be synodont and the largest non-dinosaur terrestrial tetrapod from the Trias. It is natural to know how dicynodonts became so great. Lisowicia is very interesting because it punches holes in many ideas Our classic is about reptiles' mammals-such as' Trias, 'said Dr. Grzegorz Niedzwiedzki, Uppsala University.
The first finding of fossils from Lisowice in Poland was made in 2005 by Robert Borz? Cki and Piotr Menducki. Since then, more than 1,000 bones and bone fragments have been collected from the area, including fossils from Lisowicia. This area is considered a river deposit during the Late Triassic period.
Lisowicia's findings provide the first evidence that a mammal-sized elephant wasododonted at the same time as the more famous long-necked sauropodomorph dinosaur, contrary to previous beliefs. Sauropodomorphs include species such as Diplodocus or Brachiosaurus. This fills a gap in the fossil record of the dicynodonts and it shows that some anatomical features of limbs are considered to characterize large mammals or evolved dinosaurs also in non-mammalian synapsid. Finally, these findings from Poland are the first substantial findings of dicynodonts from the Late Triassic in Europe.
"The discovery of this important new species is a once-in-a-lifetime discovery," said Dr. Tomasz Sulej.