नवम्बर 08, 2013
Scientists have mapped the genome of China’s much-loved but endangered Tibetan antelope, able to gallop across high-altitude plains at high speed
High on the mountain steppes and semi-desert landscapes of the Tibetan Plateau, the Tibetan antelope, or chiru, roams majestically over its native habitat.
For non-native mammals such as humans, exploring the plateau can induce acute mountain sickness. But, according to a new study, the endangered Tibetan antelope – a cause celebre in China since the first-wave environmental campaigning of the 1990s – has evolved exceptional mechanisms to adapt to the inhospitable terrain.
Researchers have decoded the animal’s genome sequence, revealing evidence of genetic factors associated with the species’ ability to inhabit this harsh highland environment.
Scientists from Qinghai University, BGI and other institutions found that genes involved in metabolism allowed more efficient provision of energy in conditions of low partial pressure of oxygen in the Tibetan antelope than other plain-dwelling animals, enabling it to gallop across the plains at speeds of up to 50 miles per hour.
As well as shedding light on the chiru’s ability to live at the top of the world, the data may “also open a new way to understand the adaption of low partial pressure of oxygen in human activities,” said Qingle Cai, the project manager at BGI.
The researchers may also have discovered how the Tibetan antelope protects itself from the high levels of ultraviolet radiation to which it is continually exposed on the plateau. The genome-mapping study found that the animal boasts genes involved in DNA repair and the production of ATPase, both of which counter the effects of high-level exposure.
Altitude may not be a problem for the chiru – but humans are. Demand for shawls woven from its soft undercoat has driven the animal to the brink of extinction, with numbers falling from around 1 million 50 years ago to fewer than 150,000 today.
The Beijing-Lhasa railway has also cut off key migration routes traditionally used by the chiru, though the Chinese Academy of Sciences has said there is evidence the animals are getting used to the railway. Tunnels have been built to allow the animals to cross under the rail line, but these have inadvertently facilitated illegal poaching by improving human access to remote areas, according to WWF.
The Tibetan antelope has particular resonances for China’s green activists. A campaign to save the species was among the formative experiences of emerging environmental civil society in the 1990s, involving local communities, NGOs, students and journalists, among others. The struggle of a local group of volunteers – the Wild Yak Brigade – to protect the species against poachers attracted international attention and was later portrayed in the 2004 film Kekexili: Mountain Patrol.
A Tibetan antelope named Yingying was also chosen as one of the official mascots of the 2008 Olympic Games in Beijing.
Tom Jamieson is an intern at chinadialogue