Diversity of social behavior in caviomorph rodents

Caviomorphs occupy diverse ecological niches and exhibit diverse social organization. Studies and theory derived from better-studied mammalian taxa establish an integrative and comparative framework from which to examine social systems in caviomorphs. We synthesize the literature to evaluate variation in space use, group size, mating systems, and parental care strategies in caviomorphs in the context of current hypotheses. Across species, ecological lifestyles, including diet, habitat mode, space use, and activity period, are linked to variation in social systems including mating systems, breeding strategies, and associated parental care strategies. Within species, different populations and the same populations over time vary in space use, sociality, and mating systems, with most variation explained by differences in resource distribution, predation risk, or population density. We highlight unique aspects of caviomorph biology and offer potentially fruitful lines for future research both at the inter- and intra-specific levels. Among species, better-resolved phylogenies and collation of basic natural history information, including lifestyle characteristics, especially for underrepresented families such as spiny rats (Echimyidae) and porcupines (Erethizontidae), can advance comparative studies. Within species, future studies of caviomorphs can make use of recent technological advancements in data collection (e.g. proximity data loggers) and data analysis (e.g. model selection), as well as integration of laboratory and field studies. These complementary approaches will allow us to examine the diversity of social behavior in this rich taxon at multiple levels of analysis. In doing so, we can gain unique insights into the ecological drivers and evolutionary significance of diverse social systems.