The howler monkey as a model for exploring host-gut microbiota interactions in primates

The mammalian gut microbiota is essential to many aspects of host physiology, including nutrition, metabolic activity, and immune homeostasis. Despite the existence of numerous studies of the impact of the gut microbiota on human health and disease, much work remains to be done to improve our understanding of the host-microbe relationship in nonhuman primates. Howler monkeys ( Alouatta spp.) are highly dependent on the gut microbiota for the breakdown of plant structural carbohydrates, and in this chapter we use new data describing the gut microbiome of captive and wild black howler monkeys ( A. pigra ) to develop and test two models of host-microbe interactions and bioenergetics. Improving our understanding of how spatial and temporal fluctuations in diet affect the nonhuman primate gut microbiota, and how this in turn influences host nutrition and physiology, has important implications for the study of the role that the gut microbiota plays in primate ecology, health, and conservation.