Figure 1.
Three dimensional scans of experimental footprints and a Laetoli footprint.
Contours are 1 mm. A) Contour map of modern human footprint (Subject 6) walking with a normal, extended limb gait and side view of normal, extended limb footprint. B) Contour map of modern human footprint (Subject 6) walking with a BKBH gait and side view of BKBH print. C) Contour map of Laetoli footprint (G1-37) and side view of Laetoli footprint (G1-37). Note the difference in heel and toe depths between modern humans walking with extended and BKBH gaits. Laetoli has similar toe relative to heel depths as the modern human extended limb print.
Figure 2.
Toe depths as a fraction of heel depth for BKBH, normal walking and Laetoli prints.
Laetoli values were calculated using values from topographic maps. Note that the values for Laetoli fall within the range of human normal prints but outside of the range of human BKBH prints.
Table 1.
Proportional toe depths of human footprints.
Figure 3.
Center of pressure (COP) position and ground reaction force impulse in humans walking with different limb postures.
A) COP movement during bipedal walking. Fraction from touchdown (TD) is the mean time as a fraction of stance phase when the COP passes anterior to the metatarsal heads (error bars are SEMs). B) Late stance impulses during bipedal walking. Values are mean for the ground reaction force impulse after the COP passes anterior to the metatarsal heads (error bars are SEMs). Normal is extended limb walking, BKBH 1 is walking with a slightly flexed knee and hip, BKBH 2 is walking with a deeply flexed knee and hip.