Final answer:
Long, curved phalanges are typically associated with d. suspension, where primates swing from branch to branch, aided by their very long arms and primate adaptations such as rotating shoulder joints and opposable digits.
Step-by-step explanation:
Long, curved phalanges are typically associated with suspension. This form of locomotion involves animals swinging from branch to branch, also known as brachiation. Characteristics of brachiators include very long arms and a strong shoulder girdle, which allows for a wide range of motion that is crucial for swinging through the trees. The curved phalanges provide a better grip on the branches, aiding in efficient movement through the arboreal habitat. Other primate adaptations for arboreal life include a rotating shoulder joint, separated big toes and thumbs for gripping branches, and stereoscopic vision for depth perception. As primates evolve, these features facilitate climbing and swinging, unlike terrestrial quadrupeds, which have shorter limbs, more rigid shoulders, and hands and feet less suited for grasping.