The first vertebrate live on trees

At the end of the Paleozoic period (260 million years ago), before the period of dinosaurs ruling Earth, the ancient predecessor of tree mammals to eat leaves and avoid terrestrial predators, Dr. Jörg Fröbisch , the Museum's paleontologist, in fact, concluded. The elongated fingers with the opposite thumb and a very active tail of Suminia getmanovi show the synapsid species (an animal of the same class, the precursor of mammals, whose scientific name is synapsid). ) eating this small plant is the first vertebrate capable of climbing trees.

Suminia is a relatively small animal, about 20 inches from the nose to the end of the tail. The relatives' paleozoic plant lifestyles have been particularly important because it marked the first time in the evolution of vertebrates, an animal that has begun to use food sources. eat high and get protection from predators that live on the ground. The evidence for this lifestyle is based on some skulls of very well-preserved and complete skeletons from a single red mud block discovered in the heart of Russia's Kirov region.

There are many separate specimens, some of them mature and some younger ones, especially useful in providing a complete picture of the anatomy of this animal. Fröbisch said: 'It is very rare to find many animals in the same mud block. We have specimens of all bones in this animal's body. '

Picture 1 of The first vertebrate live on trees Photograph of one of the best and most preserved preserved skeletons of the synapsid species climbing trees. Suminia getmanovi from the end of the Paleozoic period (260 million years ago) in Russia. (Photo: Diane Scott)

Finding that vertebrates that start living on the very beginning of the Earth's evolution is quite unexpected. Fröbisch said: 'This is a surprise, but very reasonable. It is a new habitat for vertebrates. There are new sources of food on the tree and these animals can avoid predators on the ground. '

The study also provides the first evidence in fossil record of food division between small plant-eating species and large underground plant-eating species. This happened shortly after the establishment of a modern terrestrial ecosystem with the number of species of herbivores, providing prey for several carnivorous species. Earlier terrestrial vertebrate communities do not have this modern structure, including instead of large-scale predators and some plant-eating species, and most of the food available by insects and underwater creatures.

This research is part of Dr. Dr.'s collaborative research. Jörg Fröbisch (Department of Geography, Museum of Reality, Chicago), and Dr. Robert Reisz (Department of Biology, University of Toronto), published in the journal Proceedings of the Royal Society B July 29.

This study was funded by the Canadian Government Scholarship Program, the German Education Exchange Organization (DAAD-Doktorandenstipendium), University of Toronto, and the Museum.

Update 17 December 2018