Models on WHY?

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Models on WHY?

• Why we became bipedal (6 hypotheses)
• Efficient bipedalism as the primary form of
  locomotion is seen only in hominins.

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BECOMING HUMAN PART 1

• NOVA

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Becoming Human review

• Lucy and bipedalism
• Habitual vs. Obligate Bipedalism
• Ossa Coxae
• Foot as stable support
• Longer legs
• Full knee extension

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Hominins (us) are Hominoids
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Hominins (us) review

• Defined by dental features, bipedal locomotion,
  large brain size, and tool making behavior
• Characteristics that developed at different
  rates, called mosaic evolution

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Biocultural Evolution The Human Capacity for
Culture

• All aspects of human adaptation, including
  technology, traditions, language, religion,
  marriage patterns, and social roles.
• Culture is a set of learned behaviors it is
  transmitted from one generation to the next
  through learning and not by biological or genetic
  means.
• Material culture is part of the cultural complex

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Oldowan Tool Industry

• The Oldowan is the first known industrial complex
  in prehistory. It takes its name from Olduvai
  Gorge, Tanzania
• Oldowan tool use is estimated to have begun about
  2.5 million years ago (mya), lasting to as late
  as 0.5 mya.
• It is thought that Oldowan tools were produced by
  several species of hominids ranging from late
  Australopithecus to early Homo.

Chopping tool
Biface tool
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Dating (relative)

• Relative dating methods. These tell you that
  something is older or younger than something else
• Stratigraphy- based on the law of superposition,
  which states that a lower layer is older than a
  higher one
• Flourine analysis, used to date remains of bone
• Biostratigraphy
• paleomagnetism

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Dating (absolute)

• Absoulte dating methods
• Chronometric (Absolute) dating methods are based
  on calendar years
• K/Ar, or potassium argon method used to date
  materials in the 5-1 mya range
• Carbon-14 method used to date organic material
  extending back to 75,000 years
• Thermoluminescence
• Uranium series dating
• Electron spin resonance (ESR)

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PALEOANTHROPOLOGY

• The Study of Old Humans

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How far back?
7 8 million years 70 of our history resides
in Africa Extensive changes in the last 10
years 1992 3-4 million 1998 4.4 2000 6 2003 7
million
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Early Hominoid Where to Look?
Rift Valley of East Africa Southern Africa
3 Major Groups Pre-australopiths
(7-4.4mya) Australopiths (4.2- 1 mya) Early
Homo (2.4 1.4)
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Lucy 3.7 3.5 mya
Don Johanson Dicovered in Hadar in 1974 Lucy in
combination w/ Leakey footprints tell us about
locomotion and stature Lucy 40 of skeleton, one
of three most complete, Pre-100,000 Accurate
Dates due to Volcanic Ash layers
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Laetoli (Ash Footprints)
Discovered in 1978
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Laetoli (Ash Footprints)

• Convergent Big Toe
• Clearly Bipedal
• Arch
• Slow Moving Strol
• Short Stride