Final answer:
Old World monkeys belong to the superfamily Cercopithecoidea within the Catarrhini group. They have narrow, downward-pointing noses, are native to Africa and Asia, and have distinct molars with two parallel ridges.
Step-by-step explanation:
The Old World monkeys belong to the superfamily known as Cercopithecoidea. These primates are part of a larger group called Catarrhini, which also includes the Hominoidea superfamily. Differing from their New World monkey counterparts with broad noses, Old World monkeys have narrow, downward-pointing noses, and their natural habitats span across Africa and Asia.
Old World monkeys are categorized into two main groups: the cheek pouch monkeys (Cercopithecinae) and leaf-eating monkeys (Colobinae). The defining characteristics of cercopithecoid primates are their molars, which feature two parallel ridges. Unlike their New World relatives, Old World monkeys do not possess prehensile tails; instead, some species have evolved ischial callosities and other adaptations suitable for both arboreal and ground-dwelling lifestyles.
It's important to note the evolutionary split between the Old World and New World monkeys, which occurred due to the continental drift that separated South America from Africa, leading to distinct evolutionary paths and adaptations in these groups of primates.