Earliest domesticated horses dated 5,500 years ago

People and horses have trekked together through at least 5,500 years of history, according to an international team of researchers reporting in Friday's edition of the journal Science.

New evidence, corralled in Kazakhstan, indicates the Botai culture used horses as beasts of burden — and as a source of meat and milk — about 1,000 years earlier than had been widely believed, according to the team led by Alan Outram of England's University of Exeter.

"This is significant because it changes our understanding of how these early societies developed," Outram said.