Does sociality affect evolutionary speed?

Why species differ in their potential for change over evolutionary time is key to understanding present and past biodiversity patterns. Change can come in two main categories, the genome content or architecture (anagenesis) and the number of species produced (cladogenesis). An overlooked source of variation in evolvability resides in the social lives of animals. In trying to foster research in this direction we offer a critical review of previous work on evolutionary speed and sociality. Most studies have been conducted by behavioral ecologists and see social interactions as knitting forces of an environment with specific selection pressures. These social pressures in turn promote evolutionary change in the characters they depend on. Most of the studies in this perspective have dealt with the effects of sexual selection on speciation while other non-sexual contexts have been relatively ignored. The second perspective is grounded on population genetics. It regards social interactions and the units formed by them as a dividing force that splits a population into smaller parts. Because of this division, the effective breeding population size is reduced and evolutionary change arising from inbreeding and drift enhanced. The current state of the art affords no conclusive answer on whether sociality promotes anagenesis and cladogenesis. Overall, we see several domains for improvement: A) Studies could benefit from a more integrative approach by measuring sexual and non-sexual selection pressures, in several social systems dimensions, and including the communicative role of social characters. Moreover, B) it is needed to encompass both sexes when investigating the link between sociality and evolutionary speed. Finally, it currently exists a gap between the theory and the empirical research that could be reduced by C) conceptually separating the potential for evolutionary change from its realization. While sociality might impact the potential speed, a myriad of variables might determine its unfolding. Some of the most important might be dependent on the fate of other lineages, as the K-Pg extinction event exemplifies. Given the exponential increase in our capacity for measuring and modeling sociality, anagenesis and cladogenesis in a more integrative manner, there is ample space for improvement in the coming years. Pushing forward this domain of research might benefit the research domains it integrates while fostering knowledge on a fundamental property of evolution, it’s timing