The Genus Homo Biocultural Challenges

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Part 3

• The Genus Homo Biocultural Challenges

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Part Outline

• Chapter 7 Homo habilis and Cultural Origins
• Chapter 8 Homo erectus and the Emergence of
  Hunting and Gathering
• Chapter 9 Archaic Homo sapiens and the Middle
  Paleolithic
• Chapter 10 Homo sapiens and the Upper Paleolithic

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Chapter 7

• Homo habilis and Cultural Origins

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Chapter Outline

• When, Where, and How Did the Genus Homo Develop?
• When Did Reorganization and Expansion of the
  Human Brain Begin?
• Why Is the Relationship Between Biological Change
  and Cultural Change in Early Homo?

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Development of Human Culture

• Some populations of early hominines began making
  stone tools to butcher animals for their meat.
• The earliest stone tools and evidence of
  significant meat eating date to about 2.6 m.y.a.

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Reorganization And Expansion Of The Human Brain

• Began at least 1.5 million years after the
  development of bipedal locomotion.
• Began in conjunction with scavenging and the
  making of stone tools.
• Marks the appearance of the genus Homo, an
  evolutionary offshoot of Australopithecus.

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Reorganization And Expansion Of The Human Brain

• Australopithecus relied on a vegetarian diet
  while developing a massive chewing apparatus.
• Homo ate more meat and became brainier.

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Early Representatives of the Genus Homo

• Since 1960 a number of fossils have been found in
  East Africa, and in South Africa, which have been
  attributed to Homo habilis.
• From the neck down, the skeleton of Homo habilis
  differs little from Australopithecus.
• Skull shows a significant increase in brain size
  and some reorganization of its structure.

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Hand bones
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Comparison of Partial Foot Skelton

• Homo habilis (center) compared with a chimpanzee
  (left) and modern human (right).

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Premolars (left) and molars (right) of
Australopithecus and Homo habilis
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Homo habilis and Other Early Hominins
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Tool Use

• Lower Paleolithic artifacts from Olduvai Gorge,
  Lake Turkana, and sites in Ethiopia required
  skill and knowledge for their manufacture.
• The oldest Lower Paleolithic tools found at
  Olduvai are in the Oldowan tool tradition.
• Oldowan choppers and flakes made the regular
  addition of meat to the diet possible.

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Brain Structure and Tool Use

• Tool making favored the development of a more
  complex brain
• Requires a vision of the tool to be made.
• Ability to recognize the kind of stone that can
  be worked.
• Requires steps to transform the raw material into
  a useful tool.

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Alternate Views of Early Human Evolution
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Sex, Gender and the Behavior of Early Homo

• Males supplied much of the meat, while females
  gathered other foods.
• Females shared a portion of what they gathered in
  exchange for meat.
• Sharing required planning and problem solving.

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Tools, Food, and Brain Expansion

• Increased consumption of meat, beginning about
  2.5 m.y.a. made new demands on coordination and
  behavior.
• Procuring meat depended on the ability to
  outthink more predators and scavengers.
• Eaters of high-protein foods do not have to eat
  as often as vegetarians, leaving time to explore
  and experiment with their environment.

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Language Origins

• There is a growing consensus that all great apes
  share an ability to develop language skills to
  the level of a 2- to 3-year-old human.
• In the wild apes display language skills through
  gestures.

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Language Origins

• Regions of the human brain that control language
  lie adjacent to regions involved in precise hand
  control.
• Oldowan toolmakers, like modern humans, were
  overwhelmingly right-handed.
• In making tools, they gripped the core in the
  left hand, striking flakes off with the right.

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Language Origins

• Handedness is associated with lateralization of
  brain functions and lateralization is associated
  with language.
• Tool making appears to have been associated with
  changes in the brain necessary for language
  development.