Inclusive fitness: a scientific revolution

Proponents of the “Extended Evolutionary Synthesis” argue that the current state of evolutionary biology departs from what was established in Modern Synthesis to such a degree that a new synthesis is needed. They present a “laundry list” of complaints concerning the core focus and assumptions of the Modern Synthesis and argue that the perspective of evolutionary biology must be shifted and these core assumptions relaxed in order to incorporate a plethora of new evolutionary factors. However, we contend that this revolution is already well underway, in the form of the inclusive-fitness research programme. We provide an overview of the inclusive-fitness revolution, charting its origins, explaining its core concepts and outlook, and describing the ways in which it has developed into a fully fledged and extraordinarily productive programme of scientific research. We then consider the apparently neglected processes and perspectives from an inclusive-fitness viewpoint. We conclude that progress in evolutionary theory is facilitated by focusing research attention on areas where there is a relatively poor fit between theoretical predictions and empirical observations, rather than complexifying models in pursuit of extra realism for its own sake.