Animal family tree research the key to survival of endangered species

She is not just another girl with a pretty face living in Washington's outermost urban sprawl.

Amani, an eye-catching cheetah feline, has a proud name that means aspiration and a strong family line that traces to Namibia and South Africa. Her rich genes make her one of the most important individuals in her small community just outside Front Royal, Virginia.

Unlike people who pay up to US$2,000 for ancestral DNA tests, Amani got hers free, courtesy of biologists at the Smithsonian Conservation Biology Institute who study her every move, hoping her cubs will help increase the thinning cheetah populations at zoos across the country.

Nestled in the Blue Ridge Mountains near Shenandoah National Park, the 1,300-hectare institute is at the forefront of an ambitious attempt by United States zoos to save animals threatened with extinction by studying them relentlessly.

Like zoos across the world, every animal at the institute and at the National Zoo in Washington is assigned a name that goes into a giant family album called a "stud book" that follows them from birth.

"We take data from every single animal in a population that is being managed," said Sarah Long, director of the population management centre at the Association of Zoos and Aquariums, which guides animal management at 220 accredited zoos.