Scientists stamp squirrel monkeys as rare species

A study has resolved a long-standing dispute concerning a small number of black-headed squirrel monkeys (Saimiri vanzolinii), which are found only in an isolated part of Brazil.

Whether the monkeys are a sub-species of another species or a species by itself was the point of dispute among scientists.

By its resolution hangs the tale of their uniqueness as primates and the need to preserve their smallest habitat in Brazil threatened by global warming.

The scientists from the University of California - Los Angeles (UCLA) in the US and six other countries used genetic and statistical analysis to find that this group of monkeys split from its sister group, called Saimiri ustus, about 500,000 years ago.

It formed a group called Saimiri boliviensis approximately 1.3 million years ago.

Researchers previously had thought that Saimiri boliviensis and Saimiri vanzolinii were the same species.

"We found strong evidence that it is a distinct, separate species. It's its own unique group," said study co-author Jessica Lynch Alfaro, adjunct assistant professor in department of anthropology at UCLA.

This understanding is particularly significant because the monkeys' survival is being threatened by climate change.

"They may lose all of their habitat. This species has the smallest, most restricted habitat of any Amazonian primate, and it has been predicted that the habitat may be drastically altered due to changes in weather patterns as a result of global warming," Alfaro added.

The findings could be particularly important in shaping efforts to conserve the biodiversity of primates in South America, the authors said.