Lab+10-+Australopithecus+locomotion

Lab 10: Australopithecine Locomotion Worksheet Part I In this activity, you will be examining casts and/or images of Australopithecus afarensis and the Laetoli Footprints (fossilized footprints associated with Au. afarensis ). For each trait below: 1. Compare the morphology of Au. afarensis with the modern human and ape. When assessing traits of the foot, use the Laetoli Footprints as a proxy for Au. afarensis foot. 2. Decide whether each trait is more similar to the bipedal human or the quadrupedal/ brachiating ape and mark the appropriate box. 3. Circle the appropriate description of the skeletal element or feature for Au. afarensis . Bipedal Trait Quadrupedal Trait Description (circle) Foramen magnum position ° ° Inferior vs. Posterior Innominate shape ° ° Short/wide vs. Long/tall Sacrum shape ° ° Short/wide vs. Long/tall Curvature of hand phalanges ° ° Slight vs. Pronounced Glenoid fossa location ° ° Lateral vs. Cranial Shape of rib cage ° ° Barrel vs. Funnel Angulation at knee ° ° Valgus knee vs. - f a

Straight Relative length of forelimbs ° ° Short vs. Long Length of toes relative to foot ° ° Short vs. Long Width of heel ° ° Wide vs. Narrow Arched foot ° ° Arched vs. Flat Big toe divergent vs. convergent ° ° Mostly convergent vs. Mostly divergent Part II Below is a drawing of an australopithecine skeleton. On the skeleton, you will be mapping the distribution of locomotive traits. 1. Pick one color to represent bipedal indicators and a different color to represent quadrupedal/brachiating indicators. Color the “Color Key” accordingly. 2. For each trait listed on the previous page, color over the regions of the skeleton in the color corresponding to whether it is more similar to bipeds or quadrupeds. (For the foramen magnum, you can color beneath the skull since it is not visible in the drawing). 3. After mapping each trait, answer the question below. - - I A

Cranium Trait: foramen magnum position Innominate Trait: innominate shape Sacrum Trait: sacrum shape Hand phalanx Trait: curvature of hand phalanges

Scapula Trait: glenoid fossa location Articulated Skeleton Traits: shape of rib cage, angulation at knee, relative length of forelimbs Laetoli Footprints Au. afarensis Traits: width of heel,

stretched by unknown is in the public domain. Cranium comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Innominate comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Sacrum comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Hand phalanx comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Scapula comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Foot comparisons by Kristen A. Broehl, derived from teaching materials at the University of Wyoming is licensed as CC BY-NC 4.0. Explorations Lab and Activities Manual CC BY-NC http://explorations.americananthro.org/