Primates

Among the classification of organisms, primates are difficult to classify unless you know the characteristics that are used to define them in comparison with other sort of mammal. Some of the distinguishing characteristics of primates include forward-facing eyes for binocular vision. This allows depth in perception as primates reliance on vision is very high. The facial features include reduced noses, snouts usually smaller or flattened. There is a distinct absence of vibrissae or whiskers, and they have relatively small, hairless ears. Primates in general have opposable thumbs for precision grip and power grip, which is aided by grasping fingers. They have flattened nails for fingertip protection and in development of very sensitive tactile pads on digits. Primates have greater facial mobility and vocal repertoire and a primitive limb structure and generalist teeth for an opportunistic, omnivorous diet. (Fleagle 1999 116-118)

There are two Suborders of the Order Primates  the suborder Strepsirhini in which lemurs and lorises belong, and the Haplorhini in which the monkeys and apes. Generally, Strepsirhini characteristics vary but include wet, naked and glandular nostrils with gap in each of its upper border and they have large, mobile ears. Most Strepsirhini are prominent whiskers and they have large eyes to adapt a nocturnal lifestyle. An example of which is the tree shrew, a small, arboreal mammal of the family Tupaiidae. They resemble squirrels and are commonly brown, gray, or olive in color. They have large eyes so they have superior vision. They can use their clawed forepaws effectively for holding food. Tree shrews are territorial, omnivorous, and extremely active. The pen-tailed tree shrew, Ptilocercus low is the most distinctive having a mouse-sized nocturnal animal, dark gray above and yellow below, with a naked, black tail bearing two fringes of white hair at the tip. Tree shrews are considered a possible model for early primate behavior. (Smithsonian National Zoological Park 2010)

Having an anatomical resemblance to the tree shrew are the Lemurs. Each type of lemur looks very different. Lemurs are prosimians, or primative primates. They vary in color from reddish brown to gray, and come in all different sizes, too. They are social animals with long limbs, flexible toes and fingers, and have long, pointy noses, which contribute to their excellent sense of smell. They have dog-like faces, protruding snout and their specialized scent glands function to allow for non-visual communication. They have tooth comb from lower incisors and canines. They have grooming claw on second digit of foot and flat nails everywhere else. Being a primate the lemur is considered related to apes and humans because of its looks. (Smithsonian National Zoological Park 2010)

Sulawesi Macaques is a type of an old world monkey that belongs to the second suborder Haplorhini and come s from the Old World. Unlike the lemurs, macaques have black skin, black hair, compact bodies, very small or almost no external tails, and limbs of equal length. There is a crest of long hairs on the top of their head which is their most distinguishing feature. Both sexes have ischial callosities or large, bare pads at the base of their tails. They have relatively flat and very narrow faces which differ from the protruding snouts of lemurs. Macaques have a very prominent brow ridge and cheekbones. They have very large canine teeth and cheek pouches. (Cawthon 2005 1)

Sharing same features as fur is the Golden-headed lion tamarins which belong to the New World Monkeys.  The golden-headed lion tamarin has black fur over its entire body except for on its head and mane, which is its distinct feature - the fur is a light to deep golden color. This golden fur is also seen on part of its tail, hands, feet, and forearms. Lion tamarins have claw-like nails instead of flat nails seen in humans and other primates. These claw-like nails aid in their locomotion patterns of quadrupedal running, clinging, and leaping between trees. Having nails at the ends of their fingertips instead of on top of their fingertips allows them to efficiently grip vertical surfaces and may help stabilize them on small branches. (Cawthon 2005 1)

The great ape and most likely to resemble human features are the Orangutans thus the name means man of the forest. Orangutans have a large, bulky body, a thick neck, very long, strong arms, short, bowed legs, and no tail. They are mostly covered with long reddish-brown hair in a large head having a prominent mouth area. Adult males have large cheek flaps which get larger as the ape ages. Very likely ours are the hands of the Orangutan hands. They have four long fingers plus an opposable thumb. Their feet have four long toes plus an opposable big toe. Orangutans can grasp things with both their hands and their feet. Orangutans have senses very similar to humans including hearing, sight, smell, taste, and touch. (Orangutan 2008)

Because of our looks, humans are considered premonkeys so classified as prosimians. As mammals, primates such as human beings possess the mammalian characteristics of endothermy  or the internal regulation of body temperature, often known as warm-bloodedness, bearing live young or placental, and feeding their young with milk produced by mammary glands. But not because human beings share the same characteristics as the mentioned animals means man evolved from apes, as Charles Darwin theorized. (Stein ad Bruce 1995 65-68) Not all primates possess the same characteristics and there is no unique characteristic that defines a primate. For instance, the loss of some primitive mammalian dentition is proven as humans having lost two premolars unlike the other primates. There are a number of rather specific primate characteristics present to some, such as details of the bones of the foot and skull. However, these characteristics alone do not justify that human beings are from apes.

Among the mentioned primates, it is the tree shrew that I liked most because it is cute. I believed the most common and numerous primates in Zoos before were the monkeys and apes since they can be easily caught and domesticated, as we observe today.

1 comments:

Douglas adam said...

very interesting , good job and thanks for sharing such a good blog.Strepsirhini and Haplorhini

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