18. What is an intermembral (IM) Index? What does it tell us about locomotion? IM Index Formula: (Humerus+Radius)/(Femur+Tibia) x100 Bipedalism - 50-80 Quadrupedalism - 80-100, (Knuckle-walking ~100) Brachiation - 100-150 19.

Find the IM index of the human. What is its locomotion? 20. Find the IM index of the chimp. What is its locomotion? 21. Find the IM index of the baboon or rhesus monkey. What is its locomotion?