By the end you should know...
Taxonomy classification terms
 When and where the first primates
evolved
 Characteristics that distinguish different
primate groups
 Various aspects of primate behavior

Taxonomy

We organize
all life into
groups, called
taxons, thanks
to Carle
Linneaus.
ORDER: Primate

FAMILY
 Hominoidea (this is a actually a super family of chimps,
gorillas, orangutans, great apes, humans and our ancestors)
○ Broken into Families: Hominoidae (humans and apes) and
Pongidae
 Lepilemuridae (several lemur species)
 Atelidae (howler and spider monkeys)

GENUS
 There are several! Examples:
○ Papio (the baboons)
○ Pongo (some chimps)
○ Pan (some chimps)
○ Homo (humans and our ancestors)

SPECIES
 There are about 200 species of primates today!
Today’s Primate Order







Today’s primates, although they vary a great
deal, share some similiarities, such as:
Wide range of body size (100g to 200kg), but
most average around 10 pounds
Large eyes with 3D depth perception
Focus on vision rather than smell (small noses)
Large brain (larger brain to body mass ration
than any other animal)
Heterodont teeth (different teeth) for a varied diet
Nails rather than claws
Primate Origins
Earliest fossils have been dated 65 million
years ago in Africa. What else happened 65
million years ago?
 Bone fossils are bones that have been replaced
with minerals, creating an exact replica.
 First primate were very small (150g to 3kg), and
had teeth that showed that they ate insects
 They were arboreal (lived in trees) and looked
kind of like a squirrel!

Teeth
Anthropologists use dental formulas to
compare humans to other primates.
 Humans have:

 2 incisors
 1 canine
 2 premolars
 3 molars
This reads 2-1-2-3
 Monkeys are 2-1-3-3

Different teeth
Incisors: Thin, blade like teeth at the front
of the mouth for snipping and clipping
 Canines: The pointed, conical teeth used
for puncturing and light crushing
 Premolars: Somewhat pointed, but
somewhat jagged for light crushing
 Molars: Heavy, flat teeth in the back of the
mouth for heavy crushing

What Do Primates Eat?

Primates exploit a variety of food sources. Most primates
eat:
 Fruit for carbohydrates and lipids
 Leaves or insects for proteins, vitamins, and minerals
 Some prosimians can make their own Vitamin C!



Many primates have anatomical specializations (such as
teeth and specialized digestive tracts) that enable them to
exploit particular foods, such as fruit, leaves, gum or insects
Tarsiers are the only primates that are obligate carnivores
The common chimpanzee will predate on other primate
species, such as the western red colobus monkey. This
sometimes involves tool use. Common chimpanzees
sharpen sticks to use as weapons when hunting mammals.
How do Primates Move?

Brachiation: arm swinging for arboreal
locomotion
 Usually small gibbons and siamangs
Bipedalism and Quadrupedalism:
walking on 2 legs and 4 legs,
respectively
 Knuckle-walking: a form of quadrupedal
walking, in which the forelimbs hold the
fingers in a flexed posture that allows
body weight to press down on the
ground through the knuckles
 Climbing and leaping are also used

Primate Social Behaviors

Primates have several different categories of social
systems. They are affected by 3 main things:
 Distribution of resources
 Group size
 Predation

Within a social group there is a balance between
cooperation and competition.
 Cooperative behaviors include social grooming (removing
parasites and cleaning wounds), food sharing, and
collective defense against predators and territory.
 Aggressive behaviors often signal competition for food,
sleeping sites or mates. Aggression is also used in
establishing dominance
Social Groups




Female transfer systems – females move away
from the group in which they were born.. The
groups formed are generally quite small. This
organization can be seen in chimpanzees
Male transfer systems – while the females
remain in their natal groups, the males will
emigrate as adolescents. Group sizes are usually
larger. This system is common among the lemurs
and some species of monkeys.
Monogamous species – a male–female bond,
sometimes accompanied by a juvenile offspring.
There is shared responsibility of parental care
and territorial defense. The offspring leaves the
parents' territory during adolescence.
Solitary species – often males who defend
territories that include the home ranges of
several females. This type of organization is
found in many lemurs and orangutans.
How Smart Are They?






Primates have advanced cognitive abilities: some make tools
and use them to acquire food and for social displays
Some have sophisticated hunting strategies requiring
cooperation, influence and rank
They are status conscious, manipulative and capable of
deception
They can recognise their kin
They can learn to use symbols and understand aspects of
human language including some relational syntax and
concepts of number and numerical sequence
Comparative studies show a trend towards higher intelligence
going from prosimians to New World monkeys to Old World
monkeys (larger), and significantly higher average cognitive
abilities in the great apes.
Apes




Most human-like
DNA is extremely close to ours
Fossils date back to 30mya
6mya, the Family Homindae appeared







Dental formula 2-1-2-3
Lack of tail
Terrestrial life style, not just arboreal
Relatively long arms
Simple molars for crushing, rather than shears
Relatively large body mass
Eventually some evolved into the genus Homo,
which are the ONLY bipedal primates
Bipedal Primates (humans)






Relatively long strong legs
An S-shaped spinal column that
can absorb stress
A wide pelvis that keeps the thighs
apart to help balance
A parallel big toe lined up with the
rest of the toes (rather than a
grasping toe)
Thighs that angle inward toward
the knees to help balance
Lateral and transverse arches built
into the foot so that we have a “tripod” and are not flat footed
Endangered Primates

Several species of
chimps, apes,
gibbons, orangutans
are endangered due
to:
 Habitat destruction from
logging, mostly in
Southeast Asia and
Breo (home of the
orangutan)
 Habitiat destruction from
agriculture in the African
Congo (where the
gorillas live)
 Poaching  (mostly for
meat)
Endangered Prosimians
Prosimians are a suborder of
the Order Primates (include
lemurs, aye-aye, galagos)
 All 50 species are endangered
due to deforestation
 Most live on Madagascar, an
island off of Africa
 www.wildmadagascar.org

DEBATE
After analyzing humans, and how primates
evolved, how they eat, how they act, how they
are anatomically similar, how they communicate
and socialize, how they live and reproduce, and
how their DNA is so similar to humans, should
the Genus Pan be included in the Genus
Homo?
 Why can’t the Pan be with the Homo, and just
have different species? Why do we have to
make distinct genuses?
 Research the issue, and be prepared to debate
next class!
