A study of prehistoric hand axes created by Neanderthals shows two distinct cultural traditions in populations in different regions of Europe, researchers say.

Scientists at the University of Southampton in Britain say the finding suggests Neanderthals were more culturally complex than previously acknowledged.

Southampton archaeologist Karen Ruebens examined the design of 1,300 stone tools originating from 80 Neanderthal sites in five European countries; France, Germany, Belgium, Britain and the Netherlands.

Comparison showed evidence two separate hand axe traditions or designs existed; one in a region now spanning southwestern France and Britain, the other in Germany and further to the East, a university release reported Monday.

"In Germany and France there appears to be two separate hand axe traditions, with clear boundaries, indicating completely separate, independent developments," Ruebens said.

Neanderthals in the western region made symmetrical, triangular and heart-shaped hand axes, while during the same time period in the eastern region they produced asymmetrically shaped bifacial knives, the study found.

"Distinct ways of making a hand axe were passed on from generation to generation and for long enough to become visible in the archaeological record," Ruebens said.

"This indicates a strong mechanism of social learning within these two groups and says something about the stability and connectivity of the Neanderthal populations."

"The transition zone in Belgium and Northern France indicates contact between the different groups of Neanderthals, which is generally difficult to identify but has been much talked about, especially in relation to later contacts with groups of modern humans," she said.