DNA Metabarcoding Reveals Dietary Network Structure in a Neotropical Bat
Community
Abstract
Bat communities in the Neotropics are some of the most diverse
assemblages of mammals on Earth, with some regions supporting more than
100 sympatric species. This diversity raises the question of how so many
species can coexist without apparently competing for resources. Because
bats are small, nocturnal, and volant, it is difficult to directly
observe their feeding habits, which has resulted in their classification
into broadly defined dietary guilds (e.g. insectivores, carnivores,
frugivores). Apart from these broad guilds, we lack detailed information
about what bats eat and therefore have only a limited understanding of
interaction networks linking bats and their arthropod, plant, and
vertebrate prey. In this study, we used DNA metabarcoding of plants,
arthropods, and vertebrates to infer the diets of 25 species of bats
from the tropical dry forests of Lamanai, Belize. We hypothesized that
bat diets recovered by metabarcoding would show a more granular
structure than implied by the broad guilds to which species have been
traditionally assigned. Our results indicate that bat communities from
Lamanai can be organized into eight distinct sub-community modules and
that bats partition food resources on a finer scale than previously
recognized. This study is the most comprehensive treatment to date of
Neotropical mammal diets at the community level, and provides a useful
framework for testing hypotheses about coexistence and niche
differentiation in the context of modern high-throughput molecular data.