Closely linked by DNA, gorillas (family Hominidae) are one of the four species of great apes that are the closest living relatives of humans – the other three are chimpanzees, bonobos and orangutans. Great apes are different from monkeys for a variety of reasons: they are larger, walk upright for a longer period of time, don’t have tails and have much larger, more developed brains.
There are four subspecies of gorillas: the eastern lowland or Grauer’s gorilla (Gorilla beringei graueri); the mountain gorilla (Gorilla beringei beringei); the western lowland gorilla (Gorilla gorilla gorilla); and the Cross River gorilla (Gorilla gorilla diehl).
Like all great apes, gorillas have arms that are longer than their legs and tend to walk on all four limbs at certain times – a movement that is called knuckle walking. Adult males are known as ‘silverbacks’ due to the distinctive silver-colored hair on their backs.
Gorillas’ appearances can vary based on sub-species, but for the most part, the western subspecies tend to be brownish gray in color, while the eastern and mountain gorillas tend to have a more blackish coat. Mountain gorillas also have longer and thicker fur which is adapted to their colder mountainous habitat. The three lowland subspecies of gorillas sport short, fine hair. Eastern lowland gorillas are the largest of the four subspecies.