Primates and Its Classification

PRIMATES AND ITS CLASSIFICATION

BY NEHA CHAUHAN

WHAT IS A PRIMATES

• First, primates are mammals of the vertebrate class: mammalian.

• + 4000 mammals• Primates are part of the subgroups of

placental mammals.

WHAT ARE PRIMATES

• Primates are difficult to characterize as an order.

• Because they lack the strong specializations.• Found in most other mammalian orders.• we can, however , point to several trends.• In their evolution that help define primates.• And are related to their arboreal.• Or tree- dwelling , ancestry.

TRENDS IN PRIMATES

• These include changes in the skeleton • mode of locomotion,• an inc. in brain size,• a shift toward smaller, fewer,• and less specialized teeth ,• and the evolution of stereoscopic vision• and a grasping hand with opposable thumb• Not all these trends took place in every primate group,• Nor did they evolve at the same rate in each group.

VARIATIONS

• In fact , some primates • Have retained certain primitive features, • Whereas others show all• Or most of these trends

CHARACTERISTICS OF PRIMATES

.Difficult to define by one or two common traits

.Primates are generalized ( rather than specialized ) mammals

.Defined by evolutionary trends

.Not all traits found in every member of the order.

1. LIMBS AND LOCOMOTION

• Tendency towards erect posture• But, primates utilize a number of types of

locomotion– Bipedal– Brachiation– Knuckle walkers– Fist walkers– Limb jumpers, etc.

HANDS AND FEET

• Great degree of Prehensility• Five digits on hands/feet (contra horses)• Opposable thumb• In most- divergent & partially opposable big

toe• Nails on all or some digits• Highly sensitive tactile pads on digit ends

2. DIET AND TEETH

• Lack of dietary specialization – most primates are generalized feeders eating a wide variety of foods

• Therefore, primates have a generalized dentition

3. SENSES AND BRAIN

• Vision enhanced• Olfaction reduced• Complex brain

4. MATURATION AND LEARNING

• As placental mammals, primates have relatively long gestation periods

• Also have few offspring, delayed maturation, longer lifespan than other mammals

• Greater dependence on learned behavior

5. BEHAVIORS

• Tend to be diurnal• Increased flexibility in behavior• Tend to live in social groups• In many primate social groups, males are

permanent members – unusual among mammals.

CLASSIFICATION OF PRIMATES

• The primate order is divided into two suborders

• The prosimians , lower primates,• Include the lemurs , lorises, tarsiers, and tree

shrews,• While the anthropoids or higher primates• Include monkeys , apes, and humans

• Order primates:• Suborder prosimii: ( lower primates) lemurs, lorises, tarsiers ,

tree shrews• Suborder anthropoidea ( higher primates)• Monkeys, apes, humans

• Superfamily Superfamily Cercopithecoidea: Macaque, baboon, proboscis monkey (Old World monkeys)

• Superfamily Ceboidea: Howler, spider, and squirrel monkeys (New World monkeys)

• Superfamily Hominoidea: Apes, humans– Family Pongidae: Chimpanzees, orangutans, gorillas– Family Hylobatidae: Gibbons, siamangs– Family Hominidae: Humans

ORDER PRIMATE

• “Primates differ from other mammals mainly in negative features, rendering more exact definition difficult and controversial. (Hill, 1972:1)”

• Presence of clavicle• Fully encircled eye orbit, • Three types of teeth• At least one pair of opposable digits• Nails instead of claws• Well developed caecum• Scrotal testes

TWO SUBORDERS

• What do you think “rhine” refers to?– Rhino– Rhinoplasty

• Old system– Prosimians– Anthropoids

Order Primate

Sub orderStrepsirrhiniStrepsirhines

SuborderHaplorhiniHaplorhine

PROSIMIANS

• Prosimians are generally small, – ranging from species the size of a mouse – up to those as large as a house cat

• They are arboreal, have five digits – on each hand and foot – with either claws or nails, – and are typically omnivorous

• They have large, forwardly directed eyes – specialized for night vision, – hence most are nocturnal

PROSIMIANS

• As their name implies • pro means "before," and simian means "ape”,

– prosimians are the oldest primate lineage, – and their fossil record extends back to the

Paleocene• During the Eocene prosimians were

– abundant, diversified, and widespread – in North America, Europe, and Asia

Prosimians: LORIS

Prosimians: LEMURS

Prosimians: TARSIERS

OLD WORLD MONKEYS: MANDRIL, SNOW MONKEYS

OLD WORLD MONKEYS: BABOONS

NEW WORLD MONKEYS: SPIDER MONKEYS

NEW WORLD MONKEYS: SQUIRREL MONKEY

ANTHROPOIDS

• Anthropoids evolved from a prosimian lineage – sometime during the Late Eocene, – and by the Oligocene – they were well established

• Anthropoids are divided into three super families.

Early History of Anthropoids

• Much of our knowledge about – the early evolutionary history of anthropoids – comes from fossils found in the Fayum district, – a small desert area southwest of Cairo, Egypt

• During the Late Eocene and Oligocene, – this region of Africa was a lush, tropical rain forest – that supported a diverse and abundant fauna and flora

• Within this forest lived many different – arboreal anthropoids as well as various prosimians

GREAT APES

• The third superfamily is the great apes, – which include gorillas and...

Chimpanzees

Thousands of Fossil Specimens

• In fact, several thousand fossil specimens • representing more than 20 species of primates

– have been recovered from rocks of this region

• One of the earliest anthropoids, • and a possible ancestor of the Old World monkeys,

– was Aegyptopithecus, • a small, fruit-eating, arboreal primate, about 5 kg

– It had monkey characteristics and ape features• and is the closest link we currently have • to Old World primates

One of the Earliest Anthropoids• Skull of Aegyptopithecus zeuxis

THANK YOU!