The representation of terrestrial vertebrate species held in ISIS zoos.

<p>The upper panel summarizes the representation of species for each taxonomic class of terrestrial vertebrates while the four lower panels summarize representation at the taxonomic order level within each class. The length of each bar is proportional to the number of species held, and each bar is color-coded by class. The darker shaded region of each bar represents the number of species that fall into the three IUCN Red List threatened categories (Vulnerable, Endangered and Critically Endangered). The number of species in each category is indicated to the right of each bar, and the percentage of these that are threatened is given in parentheses.