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Chapter 19 . Primate and Human Evolution. The Cradle of Mankind. Olduvai Gorge on the eastern Serengeti Plain, Northern Tanzania is often referred to as “The Cradle of Mankind” because of many important hominid discoveries there. Who are we?. Who are we? Where did we come from?

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Chapter 19

Primate and Human Evolution

the cradle of mankind
The Cradle of Mankind
  • Olduvai Gorge on the eastern Serengeti Plain, Northern Tanzania
    • is often referred to as “The Cradle of Mankind”
      • because of many important hominid discoveries there
who are we
Who are we?
  • Who are we?
  • Where did we come from?
  • What is the human genealogy?
  • These are basic questions
    • that we probably have all asked ourselves
back farther than we thought
Back Farther Than We Thought
  • Just as many people enjoy tracing
    • their own family history as far back as they can,
    • paleoanthropologists are discovering,
    • based on recent fossil finds,
    • that the human family tree goes back
    • much farther than we thought
hope of life
Hope of Life
  • In fact, a skull found in the African nation of Chad,
    • in 2002 and named Sahelanthropus tchadensis
      • but nicknamed Tourmaï,
      • which means "hope of life" in the local Goran language,
    • has pushed back the origins of humans
    • to nearly 7 million years ago
  • Another discovery reported in 2006
    • provides strong evidence for
    • an ancestor-descendant relationship
    • between two early hominid lines,
      • one of which leads to our own human lineage
understanding in flux
Understanding in Flux
  • So where does this leave us, evolutionarily speaking?
    • At a very exciting time, as we seek to unravel the history of our species
  • Our understanding of our genealogy
    • is presently in flux,
    • and each new fossil hominid find
    • sheds more light on our ancestry
human evolution
Human Evolution
  • Human evolution
    • is just like that of other groups
  • We have followed
    • an uncertain evolutionary path
  • As new species evolved,
    • they filled ecologic niches
    • and gave rise to descendants
    • better adapted to the changing environment
    • or they became extinct
  • Our own evolutionary history
    • has many “dead-end” side branches
new hypotheses about our ancestry
New Hypotheses About Our Ancestry
  • We examine the various primate groups,
    • in particular the origin and evolution of the hominids,
    • the group that includes our ancestors
  • However, we must point out
    • that new discoveries of fossil hominids,
    • as well as new techniques for scientific analysis
    • are leading to new hypotheses about our ancestry
continuing discoveries change our ideas
Continuing Discoveries Change Our Ideas
  • New discoveries may change
    • some of the conclusions stated here
  • Such is the nature of paleoanthropology—
    • and one reason why
    • the study of hominids is so exciting
what are primates
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
Trends in Primates
  • These include changes in the skeleton
    • and mode of locomotion,
    • an increase 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
  • In fact, some primates
    • have retained certain primitive features,
    • whereas others show all
    • or most of these trends
classification of primates
Classification of Primates
  • The primate order is divided into two suborders
    • Prosimii and Anthropoidea
  • The prosimians, or lower primates,
    • include the lemurs, lorises, tarsiers, and tree shrews,
  • while the anthropoids, or higher primates,
    • include monkeys, apes, and humans
classification of primates1
Classification of Primates
  • Order Primates:
    • Suborder Prosimii: (lower primates) Lemurs, lorises, tarsiers, tree shrews
    • Suborder Anthropoidea: (Higher primates) Monkeys, apes, humans
      • 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
  • 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
  • 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
eocene prosimian
Eocene Prosimian
  • Notharctus, a primitive Eocene prosimian
  • from North America
prosimians declined in cooler climate
Prosimians Declined in Cooler Climate
  • As the continents moved northward
    • during the Cenozoic
    • and the climate changed from warm tropical
    • to cooler midlatitude conditions,
    • the prosimian population decreased
    • in both abundance and diversity
prosimians are tropical
Prosimians Are Tropical
  • By the Oligocene, hardly any prosimians
    • were left in the northern continents
    • as the once widespread Eocene populations
    • migrated south to the warmer latitudes
    • of Africa, Asia, and Southeast Asia
  • Presently, prosimians are found
    • only in the tropical regions
    • of Asia, India, Africa, and Madagascar
  • Anthropoids evolved from a prosimian lineage
    • sometime during the Late Eocene,
    • and by the Oligocene
    • they were a well-established group
  • Anthropoids are divided into three superfamilies
new world monkey spider monkey
New World Monkey: Spider Monkey
  • New World Monkeys constitute a superfamily belonging to the suborder Anthropoidea (anthropoids)
old world monkey baboon
Old World Monkey: Baboon
  • Another superfamily of the anthropoids:
  • the Old World monkeys
hominoids chimpanzees
Hominoids: Chimpanzees
  • The honinoids, include apes and humans
early history of anthropoids
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
thousands of fossil specimens
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,
    • 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
One of the Earliest Anthropoids
  • Skull of Aegyptopithecus zeuxis,
  • one of the earliest known anthropoids
anthropoid superfamilies
Anthropoid Superfamilies
  • Anthropoids are divided into three superfamilies
    • Cercopithecoidea (Old World monkeys),
    • Ceboidea (New World monkeys),
    • and Hominoidea (apes and humans)
classification of primates2
Classification of Primates
  • Order Primates:
    • Suborder Prosimii: (lower primates) Lemurs, lorises, tarsiers, tree shrews
    • Suborder Anthropoidea: (Higher primates Monkeys, apes, humans
      • 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
old world monkey attributes
Old World Monkey Attributes
  • Old World monkeys
      • superfamily Cercopithecoidea
    • include the macaque, baboon, and proboscis monkey
    • They are characterized by close-set,
    • downward-directed nostrils
      • like those of apes and humans
    • grasping hands,
    • and a nonprehensile tail
old word monkey
Old Word Monkey
  • Superfamily Cercopithecoidea
  • the Old World monkeys
old world monkeys distribution
Old World Monkeys Distribution
  • Present-day Old World monkeys
    • are distributed in the tropical regions
    • of Africa and Asia
    • and are thought to have evolved
    • from a primitive anthropoid ancestor,
    • like Aegyptopithecus,
    • sometime during the Oligocene
new world monkeys
New World Monkeys
  • New World monkeys
      • superfamily Ceboidea
    • are found only in Central and South America
  • They are characterized
    • by a prehensile tail, flattish face,
    • and widely separated nostrils
    • and include the howler, spider, and squirrel monkeys
new world monkey
New World Monkey
  • New World Monkeys are members of the superfamily Ceboidea
no contact
No Contact
  • New World monkeys probably evolved from African monkeys
    • that migrated across the widening Atlantic
    • sometime during the Early Oligocene,
    • and they have continued evolving in isolation
    • to this present day
  • No evidence exists of any prosimian
    • or other primitive primates
    • in Central or South America
    • nor of any contact with Old World monkeys
    • after the initial immigration from Africa
  • Hominoids
    • superfamily Hominoidea
  • consist of three families:
    • the great apes
      • family Pongidae
      • which includes chimpanzees, orangutans, and gorillas
    • the lesser apes
      • family Hylobatidae
      • which are gibbons and siamangs;
    • and the hominids
      • family Hominidae
      • which are humans and their extinct ancestors
hominoid lineage
Hominoid Lineage
  • The hominoid lineage
    • diverged from Old World monkeys
    • sometime before the Miocene,
    • but exactly when is still being debated
  • It is generally accepted, however,
    • that hominoids evolved in Africa,
    • probably from the ancestral group
    • that included Aegyptopithecus
climatic shifts
Climatic Shifts
  • Recall that beginning in the Late Eocene
    • the northward movement of the continents
    • resulted in pronounced climatic shifts
  • In Africa, Europe, Asia, and elsewhere,
    • a major cooling trend began,
    • and the tropical and subtropical rain forests
    • slowly began to change to a variety of mixed forests
    • separated by savannas and open grasslands
    • as temperatures and rainfall decreased
apes adapted
Apes Adapted
  • As the climate changed,
    • the primate populations also changed
  • Prosimians and monkeys became rare,
    • whereas hominoids diversified
    • in the newly forming environments
    • and became abundant
  • Ape populations became reproductively isolated
    • from each other within the various forests,
    • leading to adaptive radiation
    • and increased diversity among the hominoids
migration of animals possible
Migration of Animals Possible
  • During the Miocene,
    • Africa collided with Eurasia,
    • producing additional changes in the climate,
    • as well as providing opportunities
    • for migration of animals
    • between the two landmasses
hominoid relationships
Hominoid Relationships
  • Two apelike groups evolved during the Miocene
    • that ultimately gave rise to present-day hominoids
  • Although there is still not agreement
    • on the early evolutionary relationships among the hominoids,
    • fossil evidence and molecular DNA similarities
    • between modern hominoid families
    • is providing a clearer picture of the evolutionary pathways
    • and relationships among the hominoids
  • The first group, the dryopithecines,
    • evolved in Africa during the Miocene
    • and subsequently spread to Eurasia,
    • following the collision between the two continents
  • The dryopithecines were a group of hominoids that varied
    • in size,
    • skeletal features,
    • and life-style
  • The best-known dryopithecine and perhaps
    • ancestor of all later hominoids
    • is Proconsul,
      • an ape-like fruit-eating animal
      • that led a quadrupedal arboreal existence,
      • with limited activity on the ground
  • The dryopithecines were very abundant
    • and diverse during the Miocene and Pliocene,
    • particularly in Africa
  • Probable appearance of Proconsul, a dryopithecine
  • The second group, the sivapithecids,
    • evolved in Africa during the Miocene
    • and then spread throughout Eurasia
  • The fossil remains of sivapithecids
    • consist mostly of jaws, skulls, and isolated teeth
  • Body or limb bones are rare,
    • limiting our knowledge
    • about what they looked like
    • and how they moved around
sivapithecids ate harder foods
Sivapithecids Ate Harder Foods
  • Sivapithecids had powerful jaws
    • and thick-enameled teeth with flat chewing surfaces,
    • suggesting a diet of harder foods such as nuts
  • It is clear from fossil evidence,
    • the sivapithecids were not involved
      • in the evolutionary branch leading to humans,
    • but were probably the ancestral stock
      • from which present-day orangutans evolved
    • In fact, one early genus, Gigantopithecus,
      • was a contemporary of early Homo in Eastern Asia
two lineages
Two Lineages
  • Although many pieces are still missing,
    • particularly during critical intervals
    • in the African hominoid fossil record,
    • molecular DNA as well as fossil evidence indicates
    • that the dryopithecines, African apes, and hominids
    • form a closely related lineage
  • The sivapithecids and orangutans
    • form a different lineage that did not lead to humans
  • The hominids (family Hominidae)
    • the primate family that includes present-day humans
    • and their extinct ancestors
    • have a fossil record extending back
    • to almost 7 million years
  • Several features distinguish them from other hominoids
  • Hominids are bipedal;
    • that is, they have an upright posture,
    • which is indicated by several modifications in their skeleton
comparison of locomotion
Comparison of Locomotion
  • Comparison between quadrupedal and bipedal locomotion
    • in gorillas and humans
  • In gorillas the ischium bone is long
    • and the entire pelvis is tilted toward the horizontal
comparison of locomotion1
Comparison of Locomotion
  • In humans the ischium bone is much shorter
  • and the pelvis is vertical
  • Comparison between quadrupedal and bipedal locomotion
    • in gorillas and humans
larger reorganized brain
Larger Reorganized Brain
  • In addition, hominids show a trend
    • toward a large and internally reorganized brain
  • An increase in brain size and organization
    • is apparent in comparing the brains of
    • a New World Monkey
larger reorganized brain1
Larger Reorganized Brain
  • In addition, hominids show a trend
    • toward a large and internally reorganized brain
  • An increase in brain size and organization
    • is apparent in comparing the brains of
  • a Great Ape
larger reorganized brain2
Larger Reorganized Brain
  • In addition, hominids show a trend
    • toward a large and internally reorganized brain
  • An increase in brain size and organization
    • is apparent in comparing the brains of
  • a present-day Human
other distinguishing features
Other Distinguishing Features
  • Other features that distinguish hominids from other hominoids include
    • a reduced face
    • and reduced canine teeth,
    • omnivorous feeding,
    • increased manual dexterity,
    • and the use of sophisticated tools
response to climatic changes
Response to Climatic Changes
  • Many anthropologists think
    • these hominid features evolved in response
    • to major climatic changes
    • that began during the Miocene
    • and continued into the Pliocene
  • During this time, vast savannas
    • replaced the African tropical rain forests
    • where the lower primates
    • and Old World monkeys had been so abundant
mixed forests and grasslands
Mixed Forests and Grasslands
  • As the savannas and grasslands
    • continued to expand,
    • the hominids made the transition
    • from true forest dwelling
    • to life to an environment
    • of mixed forests and grasslands
no clear consensus
No Clear Consensus
  • At present, no clear consensus exists
    • on the evolutionary history of the hominid lineage
  • This is due, in part,
    • to the incomplete fossil record of hominids
    • as well as new discoveries,
    • and also because some species
    • are known only from partial specimens
    • or fragments of bone
  • Because of this, there is even disagreement
    • on the total number of hominid species
some current theories
Some Current Theories
  • A complete discussion
    • of all the proposed hominid species
    • and the various competing schemes of hominid evolution
    • is beyond the scope of this course
  • However, we will discuss the generally accepted taxa
    • and present some of the current theories
    • of hominid evolution
stratigraphic record
Stratigraphic Record
  • The geologic ranges
    • for the commonly accepted species of hominids
  • Remember that although the fossil record
    • of hominid evolution is not complete,
    • what exists is well documented
  • Furthermore, the interpretation of that fossil record
    • precipitates the often vigorous
    • and sometimes acrimonious debates
    • concerning our evolutionary history
oldest known hominid
Oldest Known Hominid
  • Discovered in northern Chad's Djurab Desert
    • in July 2002,
    • the nearly 7-million-year-old skull
    • and dental remains of Sahelanthropus tchadensis
    • make it the oldest known hominid yet unearthed
    • and at or near to the time
    • when humans diverged
    • from our closest-living relative, the chimpanzee
sahelanthropus tchadensis
Sahelanthropus tchadensis
  • Discovered in Chad in 2002
  • and dated at nearly 7 million years,
  • this skull is presently
  • the oldest known hominid
when humans and chimpanzees diverged
When Humans and Chimpanzees Diverged
  • Currently, most paleoanthropologists accept
    • that the human-chimpanzee stock separated
    • from gorillas about 8 million years ago
    • and humans separated from chimpanzees
    • about 5 million years ago
oldest hominid
Oldest Hominid
  • Besides being the oldest hominid,
    • Sahelanthropus tchadensis shows a mosaic
    • of primitive and advanced features
    • that has both excited and puzzled paleoanthropologists
  • Its small brain case and most of its teeth
    • (except the canines) are chimplike
  • However, the nose, which is fairly flat,
    • and the prominent brow ridges
    • are features only seen, until now,
    • in the human genus Homo
leg bones and feet needed
Leg Bones and Feet Needed
  • It is hypothesized that Sahelanthropus tchadensis
    • was probably bipedal in its walking habits,
    • but until bones from its legs and feet are found,
    • that supposition remains conjecture
next oldest hominid
Next Oldest Hominid
  • The next oldest hominid is Orrorin tugenensis,
    • whose fossils have been dated at 6 million years
    • and consist of bits of jaw, isolated teeth,
    • finger, arm, and partial upper leg bones
  • At this time, debate continues
    • as to exactly where Orrorin tugenensis fits in the hominid lineage
ardipithecus ramidus
Ardipithecus ramidus
  • Sometime between 5.8 and 5.2 million years ago,
    • another hominid was present in eastern Africa
  • Ardipithecus ramidus kadabba is older
    • than its 4.4 million year old relative
    • Ardipithecus ramidus ramidus
  • Ardipithecus ramidus kadabba is very similar
    • in most features to Ardipithecus ramidus ramidus
    • but in specific features of its teeth
    • is more apelike than its younger relative
stratigraphic record1
Stratigraphic Record
  • The geologic age ranges
    • for the commonly accepted species of hominids
habitual bipedal walkers
Habitual Bipedal Walkers
  • Although many paleoanthropologists think
    • both Orrorin tugenensis and Ardipithecus ramidus kadabba
    • were habitual bipedal walkers
    • and thus on a direct evolutionary line to humans,
    • others are not as impressed with the fossil evidence
    • and are reserving judgment
  • Until more fossil evidence is found and analyzed,
    • any single scheme of hominid evolution presented here would be premature
  • Australopithecine is a collective term
    • for all members of the genus Australopithecus
  • Currently, five species are recognized:
    • A. anamensis,
    • A. afarensis,
    • A. africanus,
    • A. robustus,
    • and A. boisei
evolutionary scheme
Evolutionary Scheme
  • Many paleontologists accept
    • the evolutionary scheme in which
    • A. anamensis,
      • the oldest known australopithecine,
    • is ancestral to A. afarensis,
      • who in turn is ancestral to A. africanus
      • and the genus Homo,
      • as well as the side branch of australopithecines
        • represented by A. robustus and A. boisei
oldest known australopithecine
Oldest Known Australopithecine
  • The oldest known australopithecine
    • is Australopithecus anamensis
    • discovered at Kanapoi,
      • a site near Lake Turkana, Kenya,
    • by Meave Leakey
      • of the National Museums of Kenya
    • and her colleagues
similar yet more primitive
Similar Yet More Primitive
  • A. anamensis, a 4.2-million-year-old bipedal species,
    • has many features in common
    • with its younger relative, A. afarensis,
    • yet is more primitive in other characteristics,
    • such as its teeth and skull
  • A. anamensis
    • is estimated to have been
    • between 1.3 and 1.5 m tall
    • and weighed 33 to 50 kg
new fossil discovery
New Fossil Discovery
  • A discovery, reported in 2006, of fossils
    • of A. anamensis, from the Middle Awash area
      • in northeastern Ethiopia
    • has shed new light on the transition between
    • Ardipithecus and Australopithecus.
  • The discovery of Ardipithecus
    • in the same region of Africa
      • and same times as the earliest Australopithecus
    • provides strong evidence that Ardipithecus
      • evolved into Australopithecus
    • and links these two genera
    • in the evolutionary lineage leading to humans
australopithecus afarensis
Australopithecus afarensis
  • Australopithecus afarensis,
    • who lived 3.9–3.0 million years ago,
    • was fully bipedal
    • and exhibited great variability in size and weight
  • Members of this species ranged
    • from just over 1 m to about 1.5 m tall
    • and weighed between 29 and 45 kg
  • This recon-struction
  • illustrates how adaptations in
  • Lucy’s hip, leg and foot
  • allowed a fully bipedal
  • means of locomotion
  • A reconstruction of Lucy’s skeleton
    • by Owen Lovejoy
      • and his students at Kent State University, Ohio
  • Lucy is an ~ 3.5-million-year-old
    • Australopithecusafarensis
hominid footprints
Hominid Footprints
  • Preserved in volcanic ash at Laetoli, Tanzania
    • Discovered in 1978 by Mary Leakey,
    • these footprints proved hominids
    • were bipedal walkers at least 3.5 million years ago
    • The footprints of two adults and possibly those of a child
    • are clearly visible in this photograph
brain size of a afarensis
Brain Size of A. afarensis
  • A. afarensis had a brain size of 380–450 cubic centimeters (cc),
    • larger than the 300–400 cc
    • of a chimpanzee
    • but much smaller than that of present-day humans (1350 cc average)
apelike features
Apelike Features
  • The skull of A. afarensis retained many apelike features,
    • including massive brow ridges
    • and a forward-jutting jaw,
    • but its teeth were intermediate
    • between those of apes and humans
  • The heavily enameled molars
    • were probably an adaptation to chewing fruits, seeds, and roots
landscape with a afarensis
Landscape with A. afarensis
  • Re-creation of a Pliocene landscape
    • showing members of
    • Australo-pithecus afarensis
    • gathering and eating
    • various fruits and seeds
a africanus lived 3 0 2 3 mya
A. africanus Lived 3.0–2.3 mya
  • A. afarensis was stratigraphically succeeded by
    • Australopithecus africanus,
    • who lived 3.0–2.3 million years ago
  • The differences between the two species are relatively minor
  • They were both about the same size and weight,
    • but A. africanus had a flatter face
    • and somewhat larger brain
skull of a africanus
Skull of A. africanus
  • A reconstruction of the skull
    • of Australopithecus africanus
  • This skull,
    • known as that of the Taung Child,
      • was discovered by Raymond Dart in South Africa in 1924
    • and marks the beginning of modern paleoanthropology
not as well adapted for bipedalism
Not As Well Adapted for Bipedalism
  • Furthermore, it appears the limbs
    • of A. africanus may not have been
    • as well adapted for bipedalism
    • as those of A. afarensis
robust species
Robust Species
  • Both A. afarensis and A. africanus
    • differ markedly from the so-called robust species
      • A. boisei (2.6–1.0 million years ago)
      • and A. robustus (2.0–1.2 million years ago)
  • A. boisei was 1.2–1.4 m tall
    • and weighed between 34 and 49 kg
  • It had a powerful upper body,
    • a distinctive bony crest on the top of its skull,
    • a flat face, and the largest molars of any hominids
a robustus was a vegetarian
A. robustus Was a Vegetarian
  • A. robustus, in contrast,
    • was somewhat smaller (1.1–1.3 m tall)
    • and lighter (32–40 kg)
  • It had a flat face, and the crown of its skull
    • had an elevated bony crest
    • that provided additional area
    • for the attachment of strong jaw muscles
  • Its broad flat molars indicated
    • A. robustus was a vegetarian
australopithecus robustus skull
Australopithecus robustus Skull
  • The skull of Australopithecus robustus
  • This species had a massive jaw,
    • powerful chewing muscles,
    • and large broad flat chewing teeth
    • apparently used for grinding up coarse plant food
separate lineage
Separate Lineage
  • Most scientists accept the idea
    • that the robust australopithecines
    • form a separate lineage
    • from the other australopithecines
    • that went extinct 1 million years ago
the human lineage
The Human Lineage

Homo habilis

  • The earliest member of our own genus Homo
    • is Homo habilis,
    • who lived 2.5-1.6 million years ago
  • Its remains were first found at Olduvai Gorge,
      • Tanzania,
    • but it is also known
    • from Kenya, Ethiopia, and South Africa
  • H. habilis evolved from the A. afarensis and A. africanus lineage
    • and coexisted with A. africanus
    • for approximately 200,000 years
stratigraphic record2
Stratigraphic Record
  • The geologic age ranges
    • for the commonly accepted species of hominids
characteristics of homo habilis
Characteristics of Homo habilis
  • H. habilis had a larger brain (700 cc average)
    • than its australopithecine ancestors,
    • but smaller teeth
  • It was about 1.2-1.3 m tall
    • and only weighed 32-37 kg
homo habilis
Homo habilis
  • Homo habilis
  • is the earliest species of the Homo lineage
  • Shown is an approximately 1.9 million year old skull
    • from Kenya
transition from h habilis to h erectus
Transition from H. habilis to H. erectus
  • The evolutionary transition
    • from H. habilis to Homo erectus
    • appears to have occurred in a short period of time,
    • between 1.8 and 1.6 million years ago
  • New findings published in 2007 suggest
    • that H. habilis and H. erectus apparently coexisted
    • for approximately 500,000 years
transition from h habilis to h erectus1
Transition from H. habilis to H. erectus
  • Some scientists think that
    • H. habilis and H. erectus
    • may have evolved from a common ancestor
    • and represent separate lineages of Homo,
    • rather than the traditional linear view
    • of H. erectus evolving from H. habilis
homo erectus
Homo erectus
  • In contrast to the australopithecines and H. habilis,
    • which are unknown outside Africa,
    • Homo erectus was a widely distributed species,
    • having migrated from Africa during the Pleistocene
  • Specimens have been found
    • not only in Africa
    • but also in Europe, India, China ("Peking Man"),
    • and Indonesia ("Java Man")
survived in asia until about 100 000 years ago
Survived in Asia Until About 100,000 Years Ago
  • H. erectus evolved in Africa 1.8 million years ago
    • and by 1 million years ago
    • was present in southeastern and eastern Asia,
    • where it survived until about 100,000 years ago
h erectus differed from modern humans
H. erectus Differed From Modern Humans
  • Although H. erectus developed regional variations in form,
    • the species differed from modern humans in several ways
  • Its brain size of 800-1300 cc,
    • although much larger than that of H. habilis,
    • was still less than the average for Homo sapiens (1350 cc)
size similar to humans
Size Similar to Humans
  • The skull of H. erectus was thick-walled,
    • its face was massive,
    • it had prominent brow ridges,
    • and its teeth were slightly larger than those of present-day humans
  • H. erectus was comparable to size to modern humans,
    • standing between 1.6 and 1.8 m tall
    • and weighing between 53 and 63 kg
skull of homo erectus
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
h erectus was a tool maker
H. erectus Was a Tool Maker
  • The archaeological record indicates
    • that H. erectus was a toolmaker
  • Furthermore, some sites show evidence
    • that its members used fire and lived in caves,
    • an advantage for those living
    • in more northerly climates
homo erectus using tools
Homo erectus Using Tools
  • Recreation of a Pleistocene setting in Europe
    • in which members of Homo erectus are
    • using fire and stone tools
the out of africa view
The "Out of Africa" View
  • Debate still surrounds the transition
    • from H. erectus to our own species, Homo sapiens
    • Paleoanthropologists are split into two camps
  • On the one side are those who support
    • the "out of Africa" view
  • According to this camp, early modern humans
    • evolved from a single woman in Africa,
    • whose offspring then migrated from Africa,
      • perhaps as recently as 100,000 years ago
    • and populated Europe and Asia,
    • driving the earlier hominid populations to extinction
the multiregional view
The "Multiregional" View
  • The alternative explanation, the "multiregional" view
    • maintains that early modern humans
    • did not have an isolated origin in Africa,
    • but rather established separate populations throughout Eurasia
  • Occasional contact and interbreeding
    • between these populations enabled our species
    • to maintain its overall cohesiveness,
    • while still preserving the regional differences
    • in people we see today
homo sapiens evolved from h erectus
Homo sapiens Evolved From H. erectus
  • Regardless of which theory turns out to be correct,
    • our species, H. sapiens
    • most certainly evolved from H. erectus
  • Perhaps the most famous of all fossil humans are the Neanderthals,
    • who inhabited Europe and the Near East
    • from about 200,000 to 30,000 years ago
    • and according to the best estimates,
    • never exceeded 15,000 individuals in western Europe
  • Some paleoanthropologists regard the Neanderthals
    • as a variety or subspecies of our own species (Homo sapiens neanderthalensis),
    • whereas others regard them as a separate species (Homo neanderthalensis)
specimens found in neander valley
Specimens Found in Neander Valley
  • In any case, their name comes
    • from the first specimens found in 1856
    • in the Neander Valley near Düsseldorf, Germany
  • The most notable difference between Neanderthals
    • and present-day humans is in the skull
  • Neanderthal skulls were long and low
    • with heavy brow ridges, a projecting mouth,
    • and a weak, receding chin
  • Their brain was slightly larger on average
    • than our own, and somewhat differently shaped
neanderthal skull
Neanderthal Skull
  • The Neanderthals were characterized by prominent heavy brow ridges, a projecting mouth, and a weak chin.
cold adapted
Cold Adapted
  • The Neanderthal body was
    • more massive
    • and heavily muscled
    • than ours,
    • with rather short lower limbs,
    • much like those
    • of other cold-adapted people of today
  • Neanderthal males averaged between 1.6-1.7 m in height
    • and about 83 kg in weight
red hair light skin
Red Hair, Light Skin
  • In 2007, scientists announced that they had isolated a pigmentation gene
    • from a segment of Neanderthal DNA
    • that indicated that at least some Neanderthals
    • had red hair and light skin
  • Furthermore, the gene is different
    • from that of modern red-haired people,
    • suggesting that perhaps Neanderthals and present-day humans
    • developed the trait independently,
    • in response to similar
    • higher northern latitude environmental pressures
first humans in cold climates
First Humans in Cold Climates
  • Based on specimens from more than 100 sites,
    • we now know Neanderthals
    • were not much different from us,
    • only more robust
  • Europe's Neanderthals were the first humans
    • to move into truly cold climates,
    • enduring miserably long winters and short summers
    • as they pushed north into tundra country
burial ceremony in a cave
Burial Ceremony in a Cave
  • Archaeological evidence indicates
    • Neanderthals lived in caves
    • and participated in ritual burials
    • as depicted in this painting of a burial ceremony
    • such as occurred approximately 60,000 years ago
    • at Shanidar Cave, Iraq
took care of their injured
Took Care of Their Injured
  • The remains of Neanderthals
    • are found chiefly in caves
    • and hut-like rock shelters,
    • which also contain a variety
    • of specialized stone tools and weapons
  • Furthermore, archaeological evidence indicates
    • that Neanderthals commonly
    • took care of their injured and buried their dead,
    • frequently with such grave items
    • as tools, food, and perhaps even flowers
cro magnons
  • About 30,000 years ago,
    • humans closely resembling modern Europeans
    • moved into the region inhabited
    • by the Neanderthals and completely replaced them
  • Cro-Magnons, the name given to
    • the successors of the Neanderthals in France,
    • lived from about 35,000 to 10,000 years ago
  • During this period the development of art and technology
    • far exceeded anything the world had seen before
nomadic hunters
Nomadic Hunters
  • Cro-Magnons were skilled nomadic hunters,
    • following the herds
    • in their seasonal migrations
  • They used a variety of specialized tools
    • in their hunts, including perhaps the bow and arrow
  • They sought refuge in caves and rock shelters
    • and formed living groups of various sizes
cro magnon camp
Cro-Magnon Camp
  • Pleistocene Cro-Magnon camp in Europe
cave painters
Cave Painters
  • Cro-Magnons were also cave painters
  • Using paints made from manganese and iron oxides,
    • Cro-Magnon people painted hundreds of scenes
    • on the ceilings and walls of caves
    • in France and Spain,
    • where many of them are still preserved today
painting from a cave in france
Painting From a Cave in France
  • Cro-Magnons were very skilled cave painters
    • Painting of a horse
    • from the cave of Niaux, France
cultural evolution
Cultural Evolution
  • With the appearance of Cro-Magnons,
    • human evolution has become
    • almost entirely cultural rather than biological
  • Humans have spread throughout the world
    • by devising means to deal with a broad range
    • of environmental conditions
  • Since the evolution of the Neanderthals
    • approximately 200,000 years ago,
    • humans have gone from a stone culture
    • to a technology that has allowed us
    • to visit other planets with space probes
    • and land astronauts on the Moon
  • It remains to be seen
    • how we will use this technology in the future
    • and whether we will continue as a species,
    • evolve into another species,
    • or become extinct as many groups have before us
  • The primates evolved during the Paleocene
  • Several trends help characterize primates
    • and differentiate them from other mammalian orders,
      • including a change in overall skeletal structure and mode of locomotion
      • an increase in brain size
      • stereoscopic vision
      • and evolution of a grasping hand with opposable thumb
  • The primates are divided into two suborders
    • the prosimians and the anthropoids
  • The prosimians are the oldest primate lineage
    • and include lemurs, lorises, tarsiers, and tree shrews
  • The anthropoids include
    • the New and Old World monkeys,
    • apes,
    • and hominids, which are humans
      • and their extinct ancestors
  • The oldest known hominid is Sahelanthropus tchadensis,
    • dated at nearly 7 million years
    • then two subspecies of Ardipithecus at 5.8 and 4.4 million years respectively
  • These early hominids were succeeded by the australopithecines
    • a fully bipedal group that evolved in Africa 4.2 million years ago
  • Recent discoveries indicate Ardipithecus evolved into Australopithecus
  • Currently, five australopithecine species are known:
    • Australopithecus anamensis, A. afarensis, A. africanus, A. robustus and A. boisei
  • The human lineage began
    • about 2.5 million years ago in Africa
    • with the evolution of Homo habilis,
    • which survived as a species
    • until about 1.6 million years ago
  • Homoerectus evolved from H. habilis
    • about 1.8 million years ago
    • and was the first hominid to migrate out of Africa
  • Between 1 and 1.8 million years ago, H. erectus
    • had spread to Europe, India, China, and Indonesia
  • The transition from H. erectus to H. sapiens is still unresolved
    • because there is presently insufficient evidence to determine which hypothesis is correct
      • the “out of Africa”
      • or the “multiregional” hypothesis
  • Nonetheless, H. erectus
    • used fire,
    • made tools,
    • and lived in caves
  • Neanderthals inhabited Europe and the Near East
    • between 200,000 and 30,000 years ago
    • and were not much different from present-day humans
  • They were, however, more robust
    • and had differently shaped skulls
  • In addition, they made specialized tools and weapons,
    • apparently took care of their injured,
    • and buried their dead
  • The Cro-Magnons were the successors
    • of the Neanderthals
    • and lived from about 35,000-10,000 years ago
  • Cro-Magnons were highly skilled nomadic hunters,
    • formed living groups of various sizes,
    • and were also skilled cave painters
  • Modern humans succeeded the Cro-Magnons
    • about 10,000 years ago
    • and have spread throughout the world
    • as well as having set foot on the Moon