Despite decades of investigation, the precise nature of Paranthropus dietary adaptationsAdaptation remains a topic of debate. Biomechanical considerations have always been part of this debate, either implicitly or explicitly. Among the most interesting findings of the past several years is the observation that dietary reconstructions based on dentalMicrowear microwearDental microwear analysis seemingly contradict interpretations of Paranthropus dietary adaptationsAdaptation based on biomechanicsBiomechanics. Accordingly, biomechanical evidence pertaining to the feeding behavior of robust australopiths is reviewed and synthesized in reference to other sources of information about the diets of these early hominins. It is evident that species of Paranthropus possessed morphological traits that would have enhanced their ability to apply high forces to foods that were stiff and crack resistant, such as many seeds, nuts and certain underground storage organs. Many of those traits would also have constrained their ability to consume foods that were crack resistant but compliant, including leaves and grassGrass blades. Disagreement persists as to whether or not these observations meaningfully reflect dietary adaptationsAdaptation, and resolution of this debate will depend critically on improving our understanding of the mechanics of microwearMicrowear formation and the role of geological abrasives in hominin diets.