flowing toward the Old Manas Lake at the time. The cold climate of nearby Siberia influences the climate of the Dzungarian Basin, making the temperature colder—as low as —and providing more precipitation, ranging from , compared to the warmer, drier basins to the south. Runoff from the surrounding mountains into the basin supplies several lakes. The ecologically rich habitats traditionally included meadows, marshlands, and rivers. However, most of the land is now used for agriculture. It is a largely steppe and semi-desert basin surrounded by high mountains: the Tian Shan (ancient Mount Imeon) in the south and the Altai in the north. Geologically it is an extension of the Paleozoic Kazakhstan Block and was once part of an independent continent before the Altai mountains formed in the late Paleozoic. It does not contain the abundant minerals of Kazakhstan and may have been a pre-existing continental block before the Kazakhstan Block was formed. Ürümqi, Yining and Karamai are the main cities; other smaller oasis towns dot the piedmont areas. Ecology Dzungaria is home to a semi-desert steppe ecoregion known as the Dzungarian Basin semi-desert. The vegetation consists mostly of low scrub of Anabasis brevifolia. Taller shrublands of saxaul bush (Haloxylon ammodendron) and Ephedra przewalskii can be found near the margins of the basin. Streams descending from the Tian Shan and Altai ranges support stands of poplar (Populus diversifolia) together with Nitraria roborovsky, N. sibirica, Achnatherum splendens, tamarisk (Tamarix sibirimosissima), and willow (Salix ledebouriana). The northeastern portion of the Dzungarian Basin semi-desert lies within Great Gobi National Park, and is home to herds of Onagers (Equus hemionus), goitered gazelles (Gazella subgutturosa) and Wild Bactrian camels (Camelus ferus). The basin was one of the last habitats of Przewalski's horse (Equus przewalskii), also known as Dzungarian horse, which was once extinct in the wild, though it has since been reintroduced in areas of Mongolia and China. Paleontology Dzungaria and its derivatives are used to name a number of pre-historic animals, hailing from the rocky outcrops located in the Dzungar Basin: Dsungaripterus weii (pterosaur) Junggarsuchus sloani (crocodylomorph) A notable find, in February 2006, is the oldest tyrannosaur fossil unearthed by a team of scientists from George Washington University who were conducting a study in the Dzungarian Basin. The species, named Guanlong, lived 160 million years ago, more than 90 million years before the famed Tyrannosaurus rex. See also Shishugou Formation dinosaur traps Southern Xinjiang Notes