E-Mail The period preceding the emergence of behaviourally modern humans was characterised by dramatic climatic and environmental variability - it is these pressures, occurring over hundreds of thousands of years that shaped human evolution. New research published today in the Cambridge Archaeological Journal proposes a new theory of human cognitive evolution entitled 'Complementary Cognition' which suggests that in adapting to dramatic environmental and climactic variabilities our ancestors evolved to specialise in different, but complementary, ways of thinking. Lead author Dr Helen Taylor, Research Associate at the University of Strathclyde and Affiliated Scholar at the McDonald Institute for Archaeological Research, University of Cambridge, explained: "This system of complementary cognition functions in a way that is similar to evolution at the genetic level but instead of underlying physical adaptation, may underlay our species' immense ability to create behavioural, cultural and technological adaptations. It provides insights into the evolution of uniquely human adaptations like language suggesting that this evolved in concert with specialisation in human cognition."