Britannica Sources used in this answer

How do forest layers provide different places for primates to live and travel?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Illustration comparing the body plans of representative anthropoids, showing a male western lowland gorilla, a male human, a male bonobo, a female Bornean orangutan, and male and female northern white-cheeked gibbons, all labeled and depicted to scale. — primate Representative apes (superfamily Hominoidea).

In rainforests, the structural complexity of the trees creates a three-dimensional environment that serves as a home, food source, and highway for primates. These forests are broadly divided into three strata, each offering different opportunities for living and travel:1

Understory: Composed of shrubs and saplings, this layer often forms a dense, continuous horizontal surface.1
Middle Story: Characterized by trees that are in lateral contact but do not overlap, providing a distinct level for movement.1
Upper Story: Formed by tall trees with umbrella-shaped crowns, this layer creates a discontinuous canopy.1

Epiphytes and lianas further connect these layers, acting as aerial pathways that allow primates to travel through a maze of interlacing branches. While many primates are adapted to this arboreal life—using grasping hands, feet, and tails for stability—some species forage on the ground during the day but return to the trees at night for protection from predators and the elements. In contrast, savanna environments offer more limited, ground-based travel, forcing primates to adapt to terrestrial locomotion.1234