The western gorilla (Gorilla gorilla) is a great ape and the most populous species of the genus Gorilla.
Nearly all of the individuals of this taxon belong to the western lowland gorilla subspecies (G. g. gorilla) whose population is approximately 95,000 individuals. There are fewer than 300 of the only other western gorilla subspecies, the Cross River gorilla (G. g. diehli).
The western gorilla is slightly smaller, lighter, more slender and clearer dyed than its eastern cousin. The western lowland gorilla can be brown or greyish with a yellowish forehead. It also has an overhanging tip on its nose, which the eastern gorilla does not have. Males measure 160–170 cm and weigh 140 kg. Females measure 120–140 cm and weigh 60–80 kg. The western gorilla is the smaller species of the gorilla. The Cross River gorilla differs from the western lowland gorilla in both skull and tooth dimensions. It is also about 10–15 cm taller and 20–35 kg heavier, but still smaller and lighter than the mountain gorilla and the eastern lowland gorilla, latter the largest subspecies of the gorilla and the largest living primate.
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