As David Reich recently remarked on the BBC, “The standard view has been that natural selection has been quiescent in our species over the last several hundred thousand years … that paradigm is just wrong.” The paradigm he is challenging is closely associated with the neutral theory framework, which holds that most genetic variants are not subject to selection and has long shaped interpretations of human evolutionary history.
This raises an important question: to what extent are the broader implications of this reassessment fully appreciated? Many influential conclusions in human evolutionary studies—including aspects of the prevailing Out-of-Africa model, as well as interpretations in Reich’s own work—were developed under assumptions consistent with that framework.
If those assumptions require revision, it follows that at least some downstream inferences may also need to be re-examined. In this context, alternative perspectives—such as the maximum genetic diversity (MGD) theory, which posits a more pervasive role for selection—may warrant closer consideration as frameworks for reinterpreting empirical patterns.
“The standard view has been that natural selection has been quiescent in our species over the last several hundred thousand years … that paradigm is just wrong”