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".
Largest prehistoric animals
The largest-known-ever gruiform and largest phorusrhacid or "terror bird" (highly predatory, flightless birds of South America) was "Brontornis", which was about tall at the shoulder, could raise its head above the ground and could have weighed as much as . The immense phorusrhacid "Kelenken" stood tall with a skull long ( of which was beak), had the largest head of any known bird. The largest North American phorusrhacid is "Titanis", which is about tall, as tall as a forest elephant.