However, we have also discussed some very different perspectives on biological constraints. The variability selection hypothesis proposes that what distinguishes our species is the adaptation to uncertainty and to environmental novelty. In addition, the theory of gene-culture coevolution addresses situations where even within the past 10,000 years, cultural change has produced new selection pressures on the human genome (and thus, changing gene frequencies). If these approaches are correct, then they have very different implications for the way we analyze the archaeological record. We should be trying to identify a trend toward increasing diversity of cultural adaptations during the Paleolithic. We should also be trying to identify ways in which cultural changes during the past 10,000 years would have altered the contexts for natural selection on gene frequencies, and we should be testing our predictions of consequent changes in the genetic compositions of populations. If our social and cognitive abilities act not as constraints on adaptation, but as buffers that enable us to cope with a large range of environmental variation, then we should not expect to find significant selection pressures for the genetic modification of these abilities. The most intense selection pressures for genetic adaptation should be on aspects of our physiology that cannot easily be buffered against local environmental variables by social or cognitive means. These would certainly include genetic traits influencing mechanisms of disease resistance and of nutrient absorption.