PRIMATES
Chapter 14 read 935-946
Video "Life in the Trees" (students take their own notes)
LABS Comparing human pelvis’
Comparing primate skulls
Computer lab to complete www.becominghuman.org sheet
in lab book
Be sure to use internet explorer and NOT Netscape
Carl Sagan’s Universe Calendar
• 24 days = 1 billion years
• 1 second = 475 years
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“Big Bang”
Milky Way
Solar System
Life on Earth
Humanlike Primates
January 1
May 1
September 9
September 25
Milky Way
December 31, 10:30pm
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Kingdom Animalia
Phylum Chordata
class
Mammalia (mammary glands, hair, live birth)
order
Primates
family
Pongidae (gibbons, gorilla, chimpanzee)
2nd
4 genera (anthropoids)
180 species
1st closest
to humans
The Evolution of Primates
PRIMATES lack a specialized body plan
• this allows flexibility,
• unspecialized teeth (omnivores),
• opposable thumb and big toe, pentadactyl,
no claws, fingernails
• collarbone
• eyes in front, short snout, binoculaar
vision, color vision
• developed cerebellum- coordination,
cerebrum-- sensory perception
Early Primates - Traits
• Common physical primate traits:
– Dense hair or fur covering
– Warm-blooded
– Live young
– Suckle
– Infant dependence
• Common social primate traits:
– Social life
– Play
– Observation and imitation
– Pecking order
Common Primate Traits
Prosimians
a. Fat-tailed galago
(mainland Africa)
b. Ruffed lemur
(Madagascar)
c. Sifaka (Madagascar)
d. Ring-tailed lemur
(Madagascar)
e. Mouse lemur
(Madagascar)
f. Slow loris (South
Asia)
g. Aye-aye (Islands off
Anthropoids
a. Spider monkey (NW
monkey)
b. Saki monkey (NW
monkey)
c. Drill (OW terrestrial
monkey)
d. Tamarin (NW
marmoset)
e. Colobus (OW
arboreal monkey)
f. Gibbon (OW lesser
ape)
g. Gorilla (OW great
ape)
GRADES OF PRIMATES
• 1. prosimians- lemurs, lorises, aye-ayes,
tarsiers, long muzzled, furry faced,
appearing more fox-like (classification is
uncertain) Madagascar 80mybp adaptive
radiation
Lemurs, Tarsiers, Aye-Ayes, Lori
Lemurs
Tarsier
Aye-Aye
• The aye-aye shown here
lives on the island of
Madagascar. It is a very
specialized insect-eater.
• Large eyes & good
climbing abilities. The ayeaye, and most other
prosimians, differ from
monkeys and apes in
having a moist area of skin
on the nose.
Lori
Aye-aye
Loris
Madagascar
Ring tailed lemur
Tarsiers
Tarsiers
2. Anthropoidiea parallel
evolution in the 2 groups described
in the next slides. But they have in
common a furless face and
examine objects with their hands
A. platyrrhine monkeys
(Ceboids) main genus Cebus, south and
central America "New World Monkeys",
descendent of Eocene lemurs of North
America,
flat nose large nostrils,
prehensil tail
ex. howler, capuchins, squirrel monkey,
marmoset
Platyrrhine Monkeys
Platyrrhines
• Flat noses
• Nostrils point
sideways
• Many have
prehensile tails
• Live in South
and Central
America
Platyrrhine Monkeys: Tamarins
Platyrrhine Monkeys:
Capuchin Monkey
Prehensile Tail
Marmoset
• Squirrel monkey
Howler
Capuchins
B. catarrhine monkeys- Africa and
Eurasia, no tails "Old World Monkeys"
• Arboreal
• Terrestrial- macaques
and baboons
quadrapeds callas pads
on rump
• brachiation- swinging
from limb to limb
• knuckle walking
Catarrhine Monkeys
• Downwardpointing
nostrils
• Evolved and
found in Africa
and Asia
Catarrhines
Divided into two Superfamilies:
1. Old World Monkeys
2. Hominoids
– Lack tails, have larger skulls, & walk
partially upright
– Include Gibbons, Gorillas, Orangutans,
Humans, & Chimpanzees
Catarrhine Monkeys:
Mandrill and Diana
Terrestrial Old World Monkeys:
Baboon
Lesser Ape: Gibbon
Great Ape: Orangutan
Great Ape: Gorilla
Great Ape: Chimpanzee
Locomotion forms
Brachiation
Bipedalism
Knuckle walking
Laetoli, Tanzania, c. 3.5 3.8 million years ago
• a sub group **** Hominoids- great apes
and humans
• (gorilla, orangutan, chimpanzee)
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common ancestor in the Old World
What is the origin of the primates?
• DEBATE ABOUT THE EARLIEST most primitive
primate TREE SHREW
• are they primates or in the order Insectivore?
• more flexible digits, olfactory lobe diminished
• LEMURS - well developed hands, molars with 4
cusps
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• (much information from Life in the Trees video)
WHAT ABOUT HUMAN BEINGS?
• Phylogenetic tree (from article on “Man’s
earliest ancestor” article)
• approximately 15-20 mybp
Ramapithecus
Animal Connection
• Humans share many
traits with animals
• We are most similar
to apes
– Same 206 bones
– All but 3 of 650
muscles the same
– DNA is 98% the same
– Same blood types
Albino Gorilla
Humans are primates
• Primates are mammals that share
several physical characteristics.
– Pentadactylism
– 3-D color, binocular, & peripheral vision
– Prehensile, precise, & powerful gripping
– Flexible limbs
– Similar genes
Humans are primates,cont’d
• We share behaviors with other primates.
images.encarta.msn.com
– Live in family groups
– Use tools
– Commit acts of violence
– Intelligent problem solvers
f.screensavers.com
Why evolution- Why adapt?
SIGNIFICANT ENVIRONMENTAL
CHANGE
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10 mybp
E. Africa was heavily forested
volcanic activity, crustal movement
the continent of Africa was drying out
jungle breaks up into open woodland,
tropical grassland and savannah
• the features for living in trees were no
longer universally useful
• Apes remained in the forest
• Hominids adapted to the savannahs in
small steps
The Rift Valley
exploringafrica.matrix.msu.edu
images.encarta.msn.com
www.geology.iupui.edu
www.ipoaa.com/images
images.encarta.msn.com
Hominid Evolution
• Homo habilis (2.0 – 1.6mya)
• H. erectus (1.9-27kyBP)
• H. heidelbergensis
(800-100kyBP)
• H. neanderthalensis
(300-30kyBP)
• H. sapiens (130kyBP – present)
Scale: Millions of Years BP
– H. rudolfensis (2.4-1.6mya)
• What are some of the features that
distinguish an ape from a human?
• (Several overheads)
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HUMAN
APE
• bipedal
• lumbar curve
arched back
• center of gravity over pelvis
• knock-kneed- for balance in
• shifting weight when walking on one foot
• less hair
• Human
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APE
more sweat glands
muzzle does not protrude
less massive jaw
reproduction- female receptive during
lactation and throughout estrus
• shorter pelvis
• speech
FIVE TRENDS IN PRIMATE
EVOLUTION
1. skeletal changes led to upright walking, which
freed hands for new functions
2. Changes in bones and muscles led to refined
hand movements
3. Less reliance on the sense of smell and more
on daytime vision
4. Changes in diet led to fewer and less
specialized teeth
5. Brain elaboration and changes in the skull led to
speech. These developments became
interlocked with each other and with cultural
evolution
HUMAN LINEAGE
IS NOT A
STRAIGHT LINE.
Reticulate with
many dead ends
Several primates
were
contemporaries
(competition,
interbreeding?)
Hominid Evolution
• Homo habilis (2.0 – 1.6mya)
• H. erectus (1.9-27kyBP)
• H. heidelbergensis
(800-100kyBP)
• H. neanderthalensis
(300-30kyBP)
• H. sapiens (130kyBP – present)
Scale: Millions of Years BP
– H. rudolfensis (2.4-1.6mya)
• WHERE DID THIS HAPPEN? (students
have a hand out to complete)
• Great Rift Valley Ethiopia
• Earliest Hominidae (Hominids) human
features skull, femur, pelvis, foot, small
canines, molars, thicker enamel
• Australopithecus 4-5 species
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(southern ape)
"Lucy"
• A. afarensis 3-4 mybp
(brain case 380-450 cc)
How did they know it was
a woman?
• PELVIS
• less than 1/3 human
– Lucy was 3’6” tall 50 lb
• Lucy is the most complete
skeleton of an early
hominid.
– Found in Hadar, Ethiopia
(1974).
Lucy’s pelvis allowed her to
walk like a human instead of an
ape.
Fossilized Footprints
• Footprints left when a
a pair of
Australopithecines
walked in the ash of a
recently erupted
volcano
Lucy: A Transitional Fossil
• Transitional fossil shows
characteristics of two
kinds of animals
– Represent the transition
from one organism to
another
• Ape characteristics
– Skull
– Cranial capacity
• Human characteristics
– Walked upright
– Feet
– Pelvis
• A. africanus 3.5 mybp to 2.2
• (430- 550 cc) same as an ape but 1/3 the
body size
• bipedal
• 70-120 lbs
• parabolic palate
• 4-5 feet tall
• evidence of simple tools
• reduced canines
• 1-2 mybp larger skull and teeth
• (450-600 cc)
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A. robustus
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A. boisei
Homo habilis
• 1.6 -2 mybp
• (600-800 cc)
• stone tools"handy man“
• prognathic face, brow
ridge
• speech center in the
brain increased
Artist’s representation of a Homo
habilis band as it might have
existed two million years ago.
H. erectus
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.5 - 1.6 mybp (1,000 cc)
"upright man"
2 fossil groups
Java Man
Peking Man
more advanced tools
bipedalism perfected
possible use of fire
thick skull, large brow ridges
max. breath of skull at ears
------humans above the ears
Photograph of Nariokotome boy, an
early Homo erectus found near Lake
Turkana, Kenya.
Homo erectus –
1.9mybp to 27kybp
• Why was H. erectus so successful?
– Less sexual dimorphism = possible pair bonds, marriage
– Less hair on body = wearing of furs, other clothing
– Wearing of furs = ability to live further north
– Quick adaptation to
environment without physical
changes
– Culture is main reason H.
erectus was so successful
• organization for hunting
• ability to protect against
predators
• control of fire?
• possible campsites
• tools (Acheulean industry)
Distribution of H. erectus
transitional fossils
• 250,000 - 350,000 ybp
between H. erectus and
H. sapiens
• large brow ridges and a
larger cranial capacity
H. sapiens var. neandertalensis
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Neanderthals (1,450 cc)
35,000 to 130,000
Europe, Asia and Africa
5 ft. tall and stocky
Adapted to cold climates in
Europe
• heavy bones, thick brow
ridge, small chin,
buried their dead
• broad noses
The skull of the classic
Neandertal found in 1908 at
La Chapelle-aux-Saints.
• NO FOSSILS IN EUROPE 40,000 to 25, 000
• Pleistocene glaciation scraped the top layers
of the landscape off
LEFT: Reconstruction of Neandertal burial from Shanidar cave
RIGHT: Mousterian tools
• Totally new H. sapiens var. sapiens
Cro-Magnon- found in a French cave
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essentially modern man
appr. same cranial capacity
• Distinct from Neanderthals
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protruding chin
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light body build
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no brow ridges
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high forehead
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flat face
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many tools, blades ,harpoons
decorated walls with paint
Sequence of Human Evolution
One of several possibilities
Homo
neanderthalensis
Australopithecus
afarensis
Australopithecus
africanus
Common
ancestor
Homo
habilis
Homo
erectus
Homo
sapiens
Modern
apes
REPLACEMENT RADIATION model
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wave of immigrants replaced
Neanderthals
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origin of immigrants unknown
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Eastern Europe near Black Sea
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*Possible gene flow between groups
before extinctions
• Hominids have always been "polytypic"
geologic races
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some went extinct without making a
contribution
Pre-hominid Evolution
• Ardipithecus ramidus
4.4 - ?
• A. anamensis
4.2 - 3.9
• A. afarensis
4.2 - 2.5
• A. bahrelghazali
3.5 - 3.0
• A. africanus
3.5 - 2.5
• P. aethiopicus
2.7 - 2.3
• A. garhi
2.5 - ?
• P. boisei
2.3 - 1.3
• P. robustus
2.0 - 1.0
• Bipedalism
• Tools
• Language
mya
Reconstruction of Australopithecine
LAB Activity slides
Comparative Anatomy
Lucy
Gorilla
Human
• Gorilla pelvis adapted for knuckle walking
• Human pelvis adapted for upright walking
• Lucy’s pelvis very similar to human pelvis
Australopithecus
Modern human
Robust Australopithecus
Chimpanzee
www.peteducation.com
www.carolina.com
anthro.palomar.edu
www.talkorigins.org
• Questions for two articles
Art. (1) Human's earliest ancestors found
• 1. Where does the new primate fit into the
phylogenetic tree? What features places it there?
• 2. Name 4 famous anthropologists
• Art. The mystery of the Neanderthals
(2)WHAT HAPPENED TO THE NEANDERTHALS?
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2 Choices
• 1.
• 2.
• 2. Contrast the "Out of Africa" and "multiregional
continuity" theories of the H. sapiens origins.
• 3. Draw two small sketches that represent these
ideas.
• Questions for two articles
• Art. (1) Human's earliest ancestors found
• 1. Where does the new primate fit into the
phylogenetic tree? What features places it
there?
• BETWEEN THE COMMON ANCESTOR AND
A. afarensis
• UPRIGHT WALKING, LARGE TEETH, THICK
ENAMEL (parallel like an ape therefore earlier
than LUCY
• 2. Name 4 famous anthropologists
• LEAKEY (Mary, Louis, Meave, Richard) Alan
WALKER, Ian McDougall, Craig FEIBEL
• Art. The mystery of the Neanderthals
• (2)WHAT HAPPENED TO THE
NEANDERTHALS?
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2 Choices
• 1. INTERBRED WITH H. SAPIENS
• 2. EXTINCTION CAUSED BY H. SAPIENS
• 2. Contrast the "Out of Africa" and "multiregional
continuity" theories of the H. sapiens origins.
• H. erectus evolved into H. sapiens in Africa ,
then dispersed
• H. erectus moved out in to Europe and Asia and
independent groups evolved into H. sapiens
• 3. Draw two small sketches that represent
these ideas.
Modern Homo Sapiens
• Regional-Continuity Model (Milford Wolpoff, UMich)
– Humans evolved more or less simultaneously across the entire Old
World from several ancestral populations.
• Rapid-Replacement Model (Chris Stringer, NHM London)
– Humans evolved only once--in Africa from H. heidelbergensis
ancestors--and then migrated throughout the Old World,
replacing their
archaic
predecessors.
Also called the
“Out of Africa”
and “Killer Ape”
hypothesis.