This interactive web-based tool explores the taxonomic biodiversity (phylum, class, order, family, genus, and species) of animals that are housed at large zoos. The tool currently features 4 zoos: the Bronx Zoo, the Henry Doorly Zoo, the San Diego Zoo, and the Toronto Zoo. All data is from the International Species Information System (ISIS) (via globalspecies.org) and the Red List of Threatened Species documented by the International Union for Conservation of Nature. The data reflects those animals that each institution chose to report to ISIS.