A new study of DNA from ancient remains provides further evidence that farming was first spread to Europe by migrants.

It casts doubt on the alternative theory in which agriculture was adopted by Europe's existing hunter-gatherer populations, spreading via cultural exchange with neighbouring tribes.

Science journal says a team compared DNA from the skeleton of an ancient farmer with that from three hunters.

They found the "farmer" was genetically distinct from hunters.

Pontus Skoglund, from Uppsala University, Sweden, and colleagues extracted genomic DNA (genetic material contained in the nucleus of cells) from the 5,000-year-old remains unearthed in southern Sweden.