Types of Apes
The apes, which include gorillas, chimpanzees, orangutans and gibbons, are much more like human beings than monkeys or lower primates are. They have the same basic body structure, possess a high level of intelligence and may exhibit similar behavior. Chimpanzees, humans' closest living relatives, use simple tools extensively and even have culture to some degree. Different chimpanzee social groups develop their own unique tendencies and behaviors, which may be in stark contrast to the behaviors of another group. Gorillas, chimpanzees and orangutans exhibit extensive language capability as well, though they do not have the necessary physiological adaptations to produce speech. Scientists have taught apes of all three species to use sign language, as well as special computer keyboards. Apes have even invented their own words in these languages, demonstrating higher cognitive ability.
Hominids are distinguished from apes mainly by mode of locomotion. While apes predominantly use all four limbs to move along the ground, hominids have developed upright bipedal walking -- that is, they walk erect, using only their hind limbs. Switching from quadrupedal walking to bipedal walking was a crucial development in man's evolution because it freed up our ancestors' hands. This allowed them to carry and use tools while walking, which played a significant role in the development of civilization. Humans and extinct hominids are also characterized by large brains and advanced reasoning capabilities.
To make a long story short, "ape" and "monkey" are not synonymous. Apes, such as gorillas and chimpanzees, have evolved along parallel lines with human beings, and are quite close to us in a number of respects (chimpanzees and humans share 98 percent of their genetic material). On the evolutionary tree, apes are no more monkeys than we are.
See the next page for more on apes, monkeys and related topics.