Final answer:
Primates' enhanced sense of vision arises from evolutionary adaptations for life in trees and possible predatory behavior, with large eyes, color vision, stereoscopic vision, and specialized brain regions for processing visual information.
Step-by-step explanation:
Primates' enhanced sense of vision is attributed to various evolutionary adaptations. Unlike other mammals, primates have evolved to depend more on vision than on smell, as evidenced by their reduced snouts and smaller olfactory brain regions. Most rely on color vision and have forward-facing eyes that enable stereoscopic vision. This adaptation allows them to perceive their environment in three dimensions, which was crucial for their arboreal ancestors in judging distances between tree branches and aiding in locomotion without falls. Matt Cartmill's visual predation hypothesis suggests that these traits also arose as adaptations for hunting insects and small animals in forest undergrowth.
Primarily, primates evolved with large eyes positioned frontally in a flat face, complete bony eye sockets for protection, and a large occipital lobe in the brain for processing visual information. These evolutions not only facilitated life in trees but also may have supported the primates as predators. In contrast to most mammals, primates have three kinds of cones in their retinas, enhancing their color vision to perceive the world similarly to humans. The evolution of primate vision underscores the importance of sight in navigating and interacting with their complex environments.