Final answer:
Primates have evolved to live in trees, developing rotating shoulder joints, opposable thumbs, and stereoscopic vision for depth perception. These features aid them in climbing, swinging, and navigating the arboreal environment effectively.
Step-by-step explanation:
Primates exhibit numerous behavioral and physical adaptations to an arboreal lifestyle, a result of evolving in tree-rich environments. These adaptations contribute significantly to their survival and include features such as hands and feet that are adapted for climbing and brachiation. Firstly, primates have a rotating shoulder joint that allows for extensive movement necessary for swinging through trees. They also possess highly dexterous digits: most have a big toe that is widely separated from their other toes and opposable thumbs (with the exception of humans) for effective gripping of branches. Their stereoscopic vision provides them with overlapping fields of vision from both eyes, essential for depth perception and precise gauging of distances between tree limbs. Additionally, many primates have a large brain compared to other mammals, nails instead of claws, usually give birth to only one offspring at a time, and many maintain an upright body posture.