Old World Monkeys vs. New World Monkeys
Key Differences
Old World Monkeys
Old world monkeys are found in Asia and Africa. They lives in range of environment from savannah to tropical rain forest, mountainous terrain and shrubland. Old world monkeys are very closer to man because they have better developed brain, small ear pinnae, rods and cones in retina, sensitive finger tips, menstruation, continuous spermatogenesis and well developed facial muscles for expressing emotions by facial gesture. Most of the old world monkeys are at least partially omnivores but they prefer plant matter most which forms bulk of their diet. These monkeys have cheek pouches, raised nose with narrow intranasal septum and nostrils which faces downwards (catarrhine). This kind of nasal feature is also shared by humans and apes. Old world monkeys have tails but their tails lack prehensile feature. Old world monkeys have sitting pads near the tail, these thickly calloused region supports the primates to sit on trees to sleep, feed and rest. Old world monkeys have well developed finger and toe nails and their thumbs are more opposable and resembles to human thumb. Old world monkeys are rarely involved in taking care of their young ones.
New World Monkeys
New world monkeys are found in South and Central America and are confined to their arboreal habitat. New world monkeys are small to medium size primates. New world monkeys consist exclusively of arboreal (tree-dwelling) species like spider monkeys, capuchins, marmosets and tamarins. These monkeys have flat nose with broad nasal septum (platyrrhine) and they also lack cheek pouches. Their nostrils faces forward. New world monkeys have tails with prehensile feature it means that they can use their tails to grasp or hold on to different objects. Also their tails helps them in eating food as well as moving amongst the trees because their tails provide balance and support. New world monkeys have claws on their digits except the big toes of tamarins and marmosets. Thumb orientation of these monkeys lies in the line with other digits, opposes the next digit in a scissor like grip. New world monkeys lack thick calloused sitting pads (ischial callosities). New world monkeys are involved in taking care of their infants.
