The Okapi Conservation Project was established in 1987 to protect okapi populations. The center has imported okapi for breeding from the Okapi Conservation Project. The divergence of giraffe and okapi lineages dates to around 11.5 mya. While both sexes possess horns in the giraffe, only males bear horns in the okapi. The okapi can be easily distinguished from its nearest extant relative, the giraffe. The knife takes its name from the giraffe-like central African okapi. The giraffe and the okapi have characteristic long necks and long legs. "Giraffokeryx" resembled either an okapi or a small giraffe. Of the proteins in giraffe and okapi genes, 19.4% are identical. The okapi and the giraffe are the only living members of the family Giraffidae. The IUCN classifies the okapi as endangered. The district has rare fauna, including the okapi, the national animal of the Congo. The Bronx Zoo was the first zoo in North America to exhibit okapi, in 1937. The okapi inhabits canopy forests at altitudes of .