The survival chances of meerkats is being threatened by inbreeding, according to a new study. Researchers spent 20 years studying data from almost 2,000 meerkats living in clans in South Africa\'s Kalahari Desert. They found almost half of the animals showed some evidence of inbreeding. Meerkat pups that are inbred are smaller, lighter and less likely to survive in the wild than their counterparts. The project was a collaboration between scientists at the universities of Edinburgh, Cambridge and Zurich, as well as the Zoological Society of London. They recorded births and deaths and the movement of meerkats between colonies in the Kuruman River Reserve. Newborn pups were weighed and measured, their DNA analysed and their parentage determined. The researchers found that 44% of the meerkats studied showed some evidence of inbreeding. In the wild, the desert mammals live in clans of up to 50 individuals, where subordinate adults help parents care for their offspring. The scientists\' work showed that closely related meerkats never breed with each other, but that inbreeding occurred between more distantly related individuals who were unfamiliar with one another, perhaps because they lived in separate groups. Edinburgh University said the research raises questions about whether other social mammals, such as other mongooses, prairie dogs and tamarin monkeys, are similarly affected by inbreeding. The study, supported by the Natural Environment Research Council, has been published in the journal Molecular Ecology.