Washington, May 31 : A new study has shed light on the complex evolutionary history of the mammoths, suggesting they may have been closely related enough to mate when they had the chance.

In continental North America, at least two highly divergent species have long been recognized – woolly mammoths (Mammuthus primigenius) and Columbian mammoths (M. columbi).

The differences between the species have long been considered as unique adaptations to the environments where they evolved. But by piecing together trace fragments of DNA from an 11,000-year-old Columbian mammoth from Fairview, Utah, a team of Canadian, American and French researchers found that surprisingly the mitochondrial genome from this mammoth was nearly indiscernible from that of its northern woolly counterparts.

But the group does not suspect that this requires a re-write of North American mammoth evolution. "We think this individual may have been a woolly-Columbian hybrid," says Jacob Enk of the McMaster Ancient DNA Centre, the group that led the research.

"Living African elephant species interbreed where their ranges adjoin, with males of the bigger species out-competing the smaller for mates. This results in mitochondrial genomes from the smaller species showing up in populations of the larger.

“Since woolly and Columbian ranges periodically overlapped in time and space, it''s likely that they engaged in similar behaviour and left a similar genetic signal,” Enk added.

The study has been published in BioMed Central''s open access journal Genome Biology. (ANI)