The Cave at Lascaux and the Hands of Gargas Ancient humans left images painted on cave walls about 20,000 years ago. Anthropoids include monkeys, apes, and humans. Hominoids include apes and humans. Hominid refers to human lineages only.
Most primates live in tropical or subtropical forests, woodlands, or savannas.
No one feature distinguishes the primates from other mammals, but there are five trends that define the lineage. Early primates had an eye on each side of the head. Later ones had forward-directed eyes resulting in better depth perception and increased ability to discern shape, movement, color, and light intensity. Upright Walking Bipedalism is possible because of skeletal reorganization in primates ancestral to humans. A monkey skeleton is suitable for a life of climbing, leaping, and running along tree branches with palms down.