Eastern gorilla
Grauer's gorillas and mountain gorillas were previously thought to be two of the three subspecies of one single species, the gorilla ("Gorilla gorilla"). However, genetic research has shown that the two eastern subspecies are far more closely related than the western subspecies: the western lowland gorilla ("G. gorilla gorilla"), which justified the separate classification. The two eastern subspecies are now classified as "G. beringei".
Metro Richmond Zoo
The zoo has one of the largest collections of primates in the United States, with more than 200 individuals representing 30 species, such as Sulawesi macaque, Diana monkey, orangutan, cottontop tamarin, red-handed tamarin, black-handed spider monkey, lesser spot-nosed monkey, coppery titi, eastern black-and-white colobus, ring-tailed lemur, red ruffed lemur, and black-and-white ruffed lemur . The zoo has a Diana monkey breeding program.