Monday, September 12, 2011

Adaptation of the Giant Before the Ice Age

Together with several researchers, Xiaoming Wang move along Zanda Basin Tibet at an altitude of 3,700 to 4,500 meters. Afternoon in August 2007, the leg Wang paleontologists stumbled piece of fossilized bone.

Intrigued, Wang, who works at the Natural History Museum of Los Angeles County, directly perform the excavation. "Shovel me about the hairy rhino teeth," said Wang, who conducted the research with Qiang Li from the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences.

From the results of excavations, they make the reconstruction of the animal. Body length 3.5 meters with an estimated weight of 1.2-1.4 tons.
This artist's rendering shows a wooly rhino using its flattened horn to sweep snow away in order to find vegetation for food. A 3.6-million-year-old woolly rhinoceros fossil discovered in Tibet indicates that some giant mammoths, sloths and saber-tooth cats may have evolved in highlands before the Ice Age, experts say (Picture from: http://archaeologynewsnetwork.blogspot.com/)
This size is similar to the modern rhinoceros, but 10 percent smaller than the hairy rhinoceros fossils, ever found in Europe.

Rhino fossil in Europe is expected to live by the beginning of the Ice Age on Earth. Period, or own the Ice Age began to take place approximately 2.6 million to 10 thousand years ago, which gave birth to the giant mammals such as mammoths (the ancestors of modern elephants), megatherium, and indiricotherium.
Skull and lower jaw of the extinct Tibetan woolly rhino, Coelodonta thibetana (Picture from: http://www.sciencecodex.com/)
The findings of Wang and his colleagues in the southwestern Tibet increasingly attractive after the known age and anatomy of the animal. From carbon dating and other measurements, the age of the fossil is estimated to 3.6 million years old and lived in the Pleistocene period.

Moreover, these rhinos grow hair that hung against the freezing cold air. Not only that, rhino horn also has a long and straight like a canoe paddle, a layer of snow sweeper.
A, Skull and cheek teeth of Coelodonta thibetana. B, Origin, distribution, and dispersal of woolly rhinos in Eurasia (Picture from: http://archaeologynewsnetwork.blogspot.com/)
The findings of Wang and his colleagues published in the journal Science 2 September 2011. They named the new rhino Coelodonta thibetana.

These findings led scientists to a theory that, before the Ice Age began, the Tibetan plateau may be a place of great mammals evolved.

Previously, scientists did not know where the megafauna that lived in the Ice Age. Some researchers indicate these creatures come from the Arctic. "From the fossil Coelodonta thibetana, we know some of these animals come from Tibet," Wang said.

Geographically Tibetan plateau is a bit difficult for paleontologists to study. Until now only a little territory untouched by scientists.

"Cold places, such as Tibet, the Arctic and Antarctic, where the most unexpected discoveries will occur in the future-is the limit remains largely unexplored," said Wang.
A, Phylogenetic position of Coelodonta thibetana. B and C, Enamel δ13C and δ18O values of herbivores in Zanda. D-F, three large mammals from Zanda fauna: D, Blue sheep; E, Snow leopard; F, Tibetan antelope (Picture from: http://archaeologynewsnetwork.blogspot.com/)
In addition to finding fossil woolly rhinoceros, which led Wang's research team found fossils of extinct species, such as the feet of three-toed horse (Hipparion), bharal Tibet (blue sheep), chiru (Tibetan antelope), snow leopard (uncia), ferrets (meles), and 23 other mammal species.

According to Wang, when Ice Age came, these animals migrate to the plains of northern Europe and Asia. Including Coelodonta thibetana, which has been adapted to the cold air in Tibet.

"Fossil Coelodonta thibetana this is an important finding," said vertebrate paleontologist Donald R. Prothero of Occidental College in Los Angeles. According to him, the migration from Tibet is a plausible scenario. But he did not declare all mammals follow that pattern. "Nature is always more complex in real world." *** [UWD | SCIENCEMAG | NYTIMES | BBC | LIVESCIENCE | KORAN TEMPO 3641]

No comments:

Post a Comment