No animal has evolved independent of symbiotic microbes. Instead, each has coevolved with suites of microbes, most of whom are beneficial to their hosts. It is well-known that microbes are critical contributors to animal health, nutrition and development, but it also becoming increasingly clear that they contribute to animal behavior as well. Specifically, they can facilitate animals’ feeding, antipredator, reproductive and communicative behaviors. A direct way that symbiotic microbes might contribute to their hosts’ communication phenotypes is by increasing the diversity and efficacy of the chemical signals available to them. The symbiotic hypothesis for chemical signaling suggests that variation in animal chemical signals is often due to underlying variation in animals’ odor-producing microbial communities. Although historically we were unable to evaluate this hypothesis because we lacked tools to effectively characterize animals’ symbiotic microbial communities, next-generation sequencing and its associated bioinformatics approaches are rectifying the situation. I will review our research evaluating the hypothesis in hyena models, and introduce our new songbird and digital organism models as well.