Compare graphically or discuss the relationship between ener

Compare graphically or discuss the relationship between energetic costs (indexed by O2 consumption) and running speed for a large bipedal hopper (kangaroo) and quadrupedal runner (horse). Briefly explain why the line for the kangaroo looks the way you drew it.

Solution

Metabolic energy is consumed when muscle generates force and it increases with speed. As a rule animals prefer to use speed that minimizes energy needed to travel unit distance.

Kangaroos are contrast to this hypothesis. They have large tendons,bones and hind limbs which help to withstand large force during rapid acceleration which at the same time restricts restoration of elastic strain energy during steady state locomotion. Hence they prefer to gallop rather than steady state locomotion.

Horses on other side have ligaments in spine and specialised limb design. Hence like other animal they prefer to walk under normal situations rather than running to minimise oxygen demands.