Washington, Feb 13 (ANI): Closer analysis of elephant footfall patterns by scientists has suggested that the large animals can appear as both walking and running when they are moving at high speeds.
At a first glance, fast-moving elephants look as if they are walking.
But closer analysis of elephant footfall patterns by John Hutchinson from the Royal Veterinary College, UK, suggested that speedy elephants' front legs walk while their hind legs may trot.
Norman Heglund from the Universite catholique de Louvain, Belgium, realized that the only way to resolve the conundrum was to measure the immense forces exerted on the animals by the ground as they move and found that elephants run in some senses, but not in others.
To measure these forces, Heglund had to construct and calibrate an 8m long, elephant-sized force platform from sixteen 1m2 force plates.
34 elephants were employed for the experiment.
Based on the force measurements, the Belgian team was able to reconstruct the movement of each animal's centre of mass and found that the elephant's movements are extremely economical.
Consuming a minimum of 0.8J/kg/m, an elephant's cost of transport is 1/3 that of humans and 1/30 that of mice.
Heglund explained that the elephant's cost of transport is low because the animal's step frequency is higher than expected and they improve their stability by keeping an average of two feet on the ground even at high speeds, and three at lower speeds.
Combining these approaches, the elephant's centre of mass bounces less than other animals', reducing the giant's cost of transport.
Next, the team calculated the way that each animal recycles potential energy into kinetic energy to find out whether they run.
By tracking how elephants cycle potential energy into kinetic energy over the course of a stride, the team could distinguish whether the high-speed animals were running or walking.
Plotting the potential and kinetic energy of the elephants' centres of mass over the course of many strides at different speeds, the team could see that the elephants were walking like an inverted pendulum at low speeds, but as they moved faster, the kinetic and potential energy plots shifted to look like those of runners.
However, when the team analysed the movements of the elephant's centre of mass, they could see that it almost maintained a constant level as the animal shifted its weight from one side to the other, but bobbed down and up like a runner's during the second half of the stride.
So, the elephants were running by one measure, but not by another, and it seems that the forelimbs trot while the hind limbs walk at higher speeds. (ANI)