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Chapter 8. Primate and Hominin Origins. Walking on two feet?. How does that work?. Bipedalism!. To walk habitually on two feet, there had to be substantial changes to the pelvis, knees, and feet.
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Chapter 8 Primate and Hominin Origins
Walking on two feet? How does that work?
Bipedalism! To walk habitually on two feet, there had to be substantial changes to the pelvis, knees, and feet. The Pelvis is comparatively much shorter and broader than an Ape’s and extends around to the side, stabilizing the line of weight transmission from lower back to hip joint Example…
Human Os Coxae • The human os coxae is composed of three bones (right side shown).
Ossa Coxae (“hip bones”) • (a) Homo sapiens. • (b) Early hominin from South Africa. • (c) Great ape. • Note the length and breadth of the iliac blade (boxed) and the line of weight transmission.
Bipedalism! To walk habitually on two feet, there had to be substantial changes to the pelvis, legs/knees, and feet. The Legs and Knees …
Longer legs, full knee extension Land on heal ·Push off toes ·Longer limbs to maximize movement ·Full extension of Knee
Femur - The femur is angled inward, keeping legs under the body
Bipedalism! To walk habitually on two feet, there had to be substantial changes to the pelvis, legs/knees, and feet. The Feet…
Models on WHY? Why we became bipedal (6 hypotheses) Efficient bipedalism as the primary form of locomotion is seen only in hominins.