Evidence of SpeedIt’s possible sometimes to gather information from indirect evidence about an animal. The footprint of an animal may tell many things. A biologist named R. McNeill Alexander developed a formula to calculate the speed of a living animal from the trackways (series of footprints) that the animal left behind. His formula used the stride distance and hip height to calculate the speed. A TRACKWAY can be divided into three sections: The PACE, the distance between the right and left foot; the STRIDE, the distance between two successive steps (rightright, or leftleft); and the GAUGE, which is the width of the tracks, telling how close the legs were together. Measure toe to toe.
Materials
Procedures: 1. On sand (or other good footprint area) measure out 5 meters. 2. Walk or run across this area timing how long it takes to go the 5m. 3. Measure your foot length and multiply by 4 to get the hip height. 4. Measure your stride from the footprints. 5. Calculate your speeds (on data table below). 6. Compare the two methods of calculation
Formula for direct measurement: speed = = __________meters/second Formula for Indirect measurement: (Alexander's) NOTE: g= 9.8 meters/second² speed= ___________meters/second 
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