Primate Evolution
(65 - 5 mya)
Emergence of Primates

First primates


Environment - Cretaceous to Palaeocene


Plesiadapiforms or adapids and omomyids?
Continental drift (Pangea = Laurasia & Gondwanaland)
Success of primates

Arboreal theory

Visual predation hypothesis (Cartmill 1972, 1992)
Early Primates
 Prosimians
(65mya)
 Monkeys (35mya)
 Apes (23mya)
 Hominids (5mya)
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
Continents at the end of the Meszoic
Here are the
placement of the
continents at the
end of the
Cenozoic and
beginning of the
Mesozoic, about
65 m.y.a.
Classification of Primates

The primate order is divided into two suborders

The prosimians, or lower primates


include the lemurs, lorises, tarsiers, and tree shrews,
while the anthropoids, or higher primates

include monkeys, apes, and humans
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

Tarsiers are
prosimian
primates
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.
•
Ring-Tailed
Lemurs are also
prosimians
Early Cenozoic Primates

The earliest primates date to the first part of the Cenozoic
(65-54 m.y.a.).

The Eocene (54-38 m.y.a.) was the epoch of prosimians
with at least 60 different genera in two families.

The omomyid family lived in North America, Europe, and
Asia and may be ancestral to all anthropoids.

The adapid family was ancestral to the lemur-loris line.
Eocene Prosimian
Notharctus, a
primitive
Eocene
prosimian;
found in
North
America.
Omomyid
An artist’s reconstruction of
Shoshonius, a member of
the Eocene omomyid
family.
Anthropoids

Anthropoids branched off from the prosimians during the
Eocene.

Anthropoid eyes are rotated more forward compared to
prosimians.

Anthropoids have a fully enclosed bony eye socket.

Anthropoids have a dry nose separate from the upper lip.

Anthropoids have molar cusps.
New World Monkey
New World
Monkeys
constitute a
superfamily
belonging to the
suborder
Anthropoidea
(anthropoids)
Old World Monkey

Another superfamily of
the anthropoids: the Old
World Monkeys
Great Apes

The third superfamily is the
great apes, which include
gorillas and chimpanzees.
Early Anthropoids

Undisputed remains of early anthropoids date from 34
million years ago; Fayum area southwest of Cairo, Egypt
 Found remains from different types of anthropoids,
including:


Parapithecids (monkey-like)
Propliopithecids (ape-like) - some believe that the
common ancestor for both Old and New World monkeys
belonged to this group

Best known of group - Aegyptopithecus which is believed to
be after the fashion of the howler monkey
One of the
Earliest
Anthropoids

Skull of Aegyptopithecus
zeuxis
Miocene Anthropoids




Miocene Period: 24 to 5.2 million years ago
 First hominid appeared in Africa where remains have been found dating
5 million years old
Early Miocene Period
 Proconsul found in sites in East Africa
Middle Miocene
 Kenyapithecus 16 to 10 million years ago with molars resembling
modern hominoids
Late Miocene Apes
 Movement to Europe and Asia due to warmer weather conditions;
migration from Africa
 Two main groups:
 Sivapithecus - link to orangutans
 Dryopithecus
Proconsul
A skull of Proconsul
africanus from the
Kenya National
Museum.
Proposed appearance of Proconsul
africanus.
Kenyapithecus
Fossil jaw bones from
Equatorius, probably
ancestral to Kenyapithecus
africanus and K. wickeri.
Sivapithecus
Sivapithecus belongs to
the ramapithecid genera
along with
Gigantopithecus.
 Sivapithecus is now
believed to be ancestral
to the modern orangutan.

A Sivapithecus skull.
Gigantopithecus
Gigantopithecus is the largest
primate that ever lived, some
standing over 10 feet tall and
weighing 600 pounds.
 Since it died out around 250,000
years ago, it coexisted with Homo
erectus.
 Some people believe it is still alive
today as the yeti and bigfoot.

A reconstruction of Gigantopithecus
by Russel Ciochon and Bill Muns.
Dryopithecus

Dryopithecus lived in Europe
during the middle and late
Miocene.

This group probably includes
the common ancestor of the
lesser apes (gibbons and
siamangs) and the great apes.

Dryopithecus has the Y-5
arrangement of molar cusps
typical of Dryopithecus and of
hominoids.
Oreopithecus

Oreopithecus bambolii lived between 9-7 m.y.a and spent
much of its time standing upright and shuffling short
distances.

Its big toe splayed out 90 degrees from the other toes.

Oreo is Greek for “mountain”
Early Hominids
Chronology of Hominid Evolution

The Pleistocene (2 m.y.a. to 10,000 B.P.) is the epoch of
human life.

Lower Pleistocene (2 to 1 m.y.a.): Australopithecus and early
Homo

Middle Pleistocene (1 m.y.a. to 130,000 B.P.): Homo erectus
and archaic Homo sapiens

Upper Pleistocene (130,000 to 10,000 B.P.): modern Homo
sapiens
Hominid Evolution
Homo habilis (2.0 – 1.6mya)

H. rudolfensis (2.4-1.6mya)

H. erectus (1.9-27kyBP)

H. heidelbergensis (800-100kyBP)

H. neanderthalensis (300-30kyBP)

H. sapiens (130kyBP – present)
Scale: Millions of Years BP

The Varied Australopithecines

There are two major hominid genera: Australopithecus and
Homo.

However, in 1992 Berhane Asfaw and Tim D. White
discovered substantial remains considered to be from
hominids ancestral to the australopithecines; these remains
have been called Ardipithecus ramidus (thus establishing a
third hominid genus) and dated a 4.4 m.y.a.

A more recent (1995, by Maeve Leakey and Alan Walker)
discovery has been named Australopithecus anamensis and
been dated at 4.2 m.y.a.
Evolution of Bipedalism

Tool use and bipedalism (Darwin/Washburn)

Energy efficiency and bipedalism (Isbell/Young)

Radiator theory (Falk)

Body temperature and bipedalism (Wheeler)

Habitat variability and bipedalism (Potts)

Reproduction and bipedalism (Lovejoy)

Canine reduction and bipedalism (Jolly)
Skeletons
Comparison of
human and
chimpanzee
skeletons.
Pelves
A
comparison
of human
and
chimpanzee
pelves.
Dentition
Comparison of dentition in ape, human, and A. afarensis palates.
Crania Comparison
New World Monkey
Great Ape
Hominids show a trend toward
a large and internally
reorganized brain.
Human An increase in brain size and
organization is apparent when
comparing the brains of the
new world monkey, the great
ape, and the human.
Sahelanthropus tchadensis

Discovered in Chad
in 2002 and dated
at nearly 7 million
years, this skull is
presently the oldest
known hominid
The Species of Australopithecus

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
million years ago
Phylogenetic Tree
Phylogenetic tree
for African apes
and hominids.
Ardipithecus ramidus
Hominid who walked bipedally 4.4 mya
 Discovered in 1992 by Tim White in Aramis, Ethiopia (as
yet largely unpublished)
 Distinct enough to be a new species?







ape-like dentition
bipedal locomotion
overall hominid-like skeleton
small cheek teeth with thin enamel and large canines
arm bones are hominid-like
foramen magnum indicates bipedalism
Australopithecines: Robust or Gracile?
Two species of australopithecines: robust and gracile
 Most palaeoanthropologists classify robust species as
Paranthropus and gracile species as Australopithecus,
although both species are australopithecines.
 Gracile




A. anamensis, A. afarensis, A. bahrelghazali, A. africanus, A.
garhi
smaller dentition, lighter musculature
Robust


P. aethiopicus, P. boisei, P. robustus
larger teeth, massive jaws, sagittal crest
Australopithecines
Skulls of Robust (left) and Gracile (right) Australopithecines.
Australopithecus anamensis

4.2 - 3.9 mya

average weight - 110 pounds

primitive bipedalism, possibly
climbing

found primarily in Kenya

discovered in 1995
Australopithecus afarensis

4.2 mya, with oldest definite specimen placed at 3.8 mya

apelike features (long arms, prognathic face, toothrow, brain
capacity)

pelvis, leg, feet, and foramen magnum all indicate bipedalism

first discovered by Don
Johanson in 1974 and called
“Lucy”

thought to be the “missing link”
until A. anamensis was
discovered 20 years later
Australopithecus afarensis
Left: Trail of
footprints of A.
afarensis made
in volcanic ash,
discovered by
Mary Leakey at
Laetoli.
Right: Closeup of footprint
at Laetoli
Landscape with A. afarensis
 Re-creation
of
a Pliocene
landscape
showing
members of
Australopithecus
afarensis
gathering and
eating various
fruits and seeds.
Australopithecus bahrelghazali
3.5 - 3.0 mya
 discovered by Michel Brunet in Bahr el Ghazal, Chad in
1995
 assumed bipedalism (few post-cranial remains)

A. africanus






3.5 - 2.5 mya
3.8 - 4.5 feet tall, 55130 lbs
ape-like tibia, grasping
big toes
wide pelvis, parabolic
tooth row
primitive bipedalism
first found by Raymond
Dart in Taung, South
Africa in 1925
Australopithecus garhi

possibly the direct ancestor of early Homo

larger molars than afarensis, but not as large as
Paranthropus

lacks enlarged brain of early Homo

toolmaker and butcher

2.5 mya
Paranthropus aethiopicus
2.7 to 2.3 mya
 earliest robust australopithecine, but least well known
 larger dentition, cheek bones, dish-shaped faces, sagittal
crests
 resembles afarensis but with increases in dental apparatus
size
 assumed bipedalism
 first discovered in Omo, Ethiopia, 1967-1974

The Black Skull - P. aethiopicus
The “black skull”,
dated to 2.5 m.y.a., was
discovered by Alan
Walker in 1985 near
Lake Turkana.
Paranthropus boisei
2.3 - 1.3 mya; 4.1 - 4.5 feet tall, 75-175 lbs
 discovered by Louis Leakey at Olduvai Gorge in Tanzania
in 1959
 originally named Zinjanthropus
 dished face, sagittal crest
 parabolic toothrow, wide pelvis
 primitive bipedalism

Paranthropus robustus
2.0 - 1.0 mya; 3.6 - 4.3 feet tall; 70-175 lbs
 discovered by Robert Broom in 1938 at Kromdraai, South
Africa, who created the name Paranthropus
 dished face, sagittal crest
 parabolic toothrow, human-like
big toes, wide pelvis, no diastema
for canines
 bipedalism (more primitive than
modern human walking)

Map of Australopithecine Finds
Map of Australopithecus sites in
Africa, with a focus on the East
African rift valley and limestone
caves of South Africa.
Facts about Australopithecines
Species
Dates
(m.y.a.)
Known
Dist.
Important
Sites
Body
Weight
(Mid-sex)
Brain Size
(Mid-sex)
(cm3)
Homo sapiens
sapiens
modern
world-wide
Beijing,
New York,
London,
Nairobi
60kg/132lbs
1,350
Pan troglodytes
modern
central
Africa
Gombe,
Mahale
42kg/93 lbs
390
Australopithecus
boisei
2.6? to 1.2
E. Africa
39 kg/86 lbs
490
Australopithecus
robustus
2.6? to 2.0?
S. Africa
Olduvai,
East
Turkana
Kromdraai
Swartkrans
37 kg/81 lbs
540
Facts about Australopithecines
Species
Dates
(m.y.a.)
Known
Dist.
Important
Sites
Body
Weight
(Mid-sex)
Brain Size
(Mid-sex)
(cm3)
Australopithecus
africanus
3.0 to 2.5?
S. Africa
Taung,
36 kg/79 lbs
Sterkfontein
Australopithecus
afarensis
3.8 to 3.0
E. Africa
Laetoli,
Hadar
35 kg/77 lbs
430
Australopithecus
anamensis
4.2
E. Africa
Kanapoi
Insufficient
data
no
published
skulls
Ardipithecus
ramidus
4.4
E. Africa
Aramis
Insufficient
data
no
published
skulls
490
Homo habilis
612 cc brain
2.3 - 1.6 mya
first toolmaker
prognathic face, brow ridge
probable meat-eater
possibly arboreal
discovered in 1960 by Leakeys
no speech
Artist’s representation of a Homo
habilis band as it might have existed
two million years ago.
Skull of Homo erectus

A reconstruction of the skull of
Homo erectus, a widely
distributed species whose
remains have been found in
Africa, Europe, India, China,
and Indonesia.
Homo erectus
1891 - Eugene Dubois
discovers H. erectus in Java
Dubois calls it
Pithecanthropus erectus
initially, also dubbed “Java
Man”
finds in China called
Sinanthropus
dates from 1.9 mya to 27,000
years B.P.
994 cc brain size (compare to
612 for H. habilis)
Acheulean tool industry
Photograph of Nariokotome boy, an early
Homo erectus found near Lake Turkana,
Kenya.
Neanderthal Skull


Reconstructed
Neanderthal
skull
The
Neanderthals
were
characterized by
prominent heavy
brow ridges and
weak chin
Homo neanderthalensis
discovered in the Neander Valley
(Tal) near Dusseldorf, 1856
 massive brain--about 1,400cc on
average
 large torso, short limbs, broad
nasal passages
 later remains show decrease in
robustness of the front teeth and
face, suggesting use of tools
replaced teeth
 retained occipital torus, some
mid-facial prognathism

The skull of the classic Neandertal
found in 1908 at La Chapelle-auxSaints.
Homo sapiens

Archaic – 100,000 to
35,000 years BP


Sometimes called Homo
sapiens and Homo sapiens
neanderthalensis
Modern – 35,000 years
BP to present

Anatomically modern

Sometimes called Homo
sapiens sapiens
Cro-Magnon Man
Cro-Magnon humans
35,000 years B.P. in
western Europe to
17,000 years B.P.
1,600 cc cranial capacity
Name comes from a
hotel in France
Not a different species,
just old Homo sapiens
from Europe
Artist’s reconstruction of a Cro-Magnon man
Archaic H. sapiens Culture
Art
Traces of art found in beads, carvings, and
paintings
Cave paintings in Spain and southern France
showed a marked degree of skill
Female figurines
27,000 to 22,000 years B.P.
Called “venuses,” these figurines depicted women
with large breasts and broad hips
• Perhaps it was an example of an ideal type, or
perhaps an expression of a desire for fertility
Archaic H. sapiens Culture
Cave paintings from 20,000 years ago at Vallon-Pontd’Arc in southern France (left) and from Lascaux, in
southwest France

Cave paintings



Mostly animals on bare walls
Subjects were animals favored for their meat
and skins
Human figures were rarely drawn due to taboos
and fears that it would somehow harm others
Upper Palaeolithic –
Hotbed of Culture





40 – 10k yBP
Shelters
 15,000 yBP Ukraine
 Some made with mammoth bones
 Wood, leather working; carpentry
Tools
 From cores to blades
 Specialization
 Composite tools
 Bow and arrow
Domestication of dogs
Gathering rather than hunting became
the mainstay of human economies.
Top: Straw Hut
Left: Mammoth bone hut
Bottom: Tool progression
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.
Social Organization

Hunter-gatherer analogy


Small group, low population density, nomadism, kinship
groups
Migration




North America was the last colonized by hominids.
Beringia (land bridge) between Russia and Alaska
Asian origin of Native Americans
30,000 to 12,000 years B.P. was first migration