An Amazonian tribe has been discovered that has no concept of time or dates, scientists said today.

The Amondawa people of Brazil do not even have words for 'time', 'week', 'month' or 'year', lead researcher Chris Sinha, of the University of Portsmouth, said.

In his study, published in the journal Language and Cognition, he argues that it is the first time scientists have been able to prove time is not a deeply entrenched universal human concept, as previously thought.