
The picture here is a Mountain Gorilla (Gorilla beringei). The species was first describe in 1847 by Thomas Staughton Savage, an American physician missionary. The males blue-black saddle (back side) turns white or silver with age, hence the term "silverbacks." Mountain Gorillas like high altitude terrains and are found in protected areas in the Democratic Republic of Congo (DRC), Rwanda and Uganda. These gentle giants are herbivorous meaning they only eat plants.
The social groupings they form are called harems. They are called such because the one or two dominant males surround themselves with unrelated females. This is unusual because in many other primates the females are all related. It is usually the kinship bonds between the females that allow for stable groups in these other primates, but in these gorillas the relationships are based purely on the individual relationships of the females to the silverback. When young gorillas reach maturity they leave the group. A young female will attach herself to another young male or find a new harem to incorporate herself into. Young males will remain solitary until they can attract females to themselves and start a harem of their own.
The mountain gorillas have some of the smallest populations of gorillas and it is estimated that between 650 and 680 individuals exist in the wild (Gray et al., 2003 and McNeilage et al., 2001).
To find out more, click the link above or go to Year of the Gorilla, Koko.org, or the Dian Fossey Gorilla Fund. Just to help you remember, Koko is the gorilla who has an amazing vocabulary in American Sign Language and Dian Fossey wrote the book Gorillas in the Mist. The movie was based on her life.