The Omnivore’s Dilemma: The Paradox of the Generalist Predators

Claire T. Hemingway, M. May Dixon, and Rachel A. Page

Phyllostomid bats are known for their spectacular radiation into distinct dietary niches. But many phyllostomid species actually have quite generalized diets. Historically, these generalist phyllostomids fell within the subfamily Phyllostominae, a diverse group that primarily hunts insects and small vertebrates such as frogs, lizards, birds, rodents, and other species of bats. This now paraphyletic group consists of over 30 species. While this group is characterized by predators with broad, generalized diets, many of these bats have distinct, specialized foraging strategies. We discuss the apparent paradox of these generalist predators: bats that can be classified as dietary generalists, broadly overlapping with one another in the prey they consume, but often possessing quite specialized foraging adaptations and distinct behavioral strategies for prey finding. To untangle the puzzle of this understudied and historically elusive group of generalist predators, we examine the influences of diet breadth on hunting behavior, spatial distribution, conservation concern, and morphology.