Navigation Links
Are high speed elephants running or walking?
Date:2/11/2010

Most animals don't think anything of breaking into a run: they switch effortlessly from walking to a high-speed bouncing run. But what about elephants? Their sheer size makes it impossible for them to bounce up in the air at high speeds. So how are high-speed elephants moving: are they running or walking? At a first glance, fast-moving elephants look as if they are walking, according to John Hutchinson from the Royal Veterinary College, UK. But closer analysis of elephant footfall patterns by Hutchinson suggested that speedy elephants' front legs walk while their hind legs may trot. Norman Heglund from the Universit catholique de Louvain, Belgium, realised 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. They publish their results on 12 February 2010 in The Journal of Experimental Biology at http://jeb.biologists.org.

To measure these forces, Heglund had to construct and calibrate an 8m long, elephant-sized force platform from sixteen 1m2 force plates. Crating the 300kg force plates, cameras and computers in Belgium and shipping the equipment to the Thai Elephant Conservation Centre in Lampang, Thailand, Heglund, Joakim Genin, Patrick Willems, Giovanni Cavagna and Richard Lair built a reinforced concrete foundation and assembled the force platform ready to measure the enormous ground reaction forces generated by the animals.

Encouraged to move by their mahouts, 34 elephants ranging from an 870kg baby up to a 4 tonne adult moved over the force platform at speeds ranging from a 0.38m/s stroll to a 4.97m/s charge. 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 explains 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. According to Heglund, running animals continually recycle potential energy stored in tendons and muscles into bouncing kinetic energy just like a pogo stick while walking animals convert potential energy at the start of a stride into kinetic energy as they step forward much like an inverted swinging pendulum. 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. 'High-speed locomotion in an elephant doesn't fall nicely into a classic category like a run or a trot. It really depends on your definition of "run",' says Heglund.


'/>"/>

Contact: Kathryn Knight
kathryn@biologists.com
44-787-634-4333
The Company of Biologists
Source:Eurekalert

Related biology news :

1. Primate sperm competition: speed matters
2. New technology identifies warped fingerprints at warp speed
3. Microarray sequence capture speeds large-scale resequencing of targeted genomic regions
4. Speed plays crucial role in breaking proteins H-bonds
5. NSF awards Williams funding for high-speed imaging faciltity
6. Software developed by Boston College lab delivers speed and accuracy to genome research
7. Licking your wounds: Scientists isolate compound in human saliva that speeds wound healing
8. New tool to speed cancer therapy approval available
9. Galloping and breathing at high speed
10. Bee swarms follow high-speed streaker bees to find a new nest
11. Nanoscopic screening process to speed drug discovery
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/2/2017)... YORK , March 2, 2017 Summary ... better understand Perrigo and its partnering interests and activities since ... ... Partnering Deals and Alliance since 2010 report provides an in-depth ... leading life sciences companies. On demand company reports ...
(Date:3/2/2017)... 2017 Australian stem cell and regenerative medicine ... signed an agreement with the Monash Lung Biology Network, ... Institute and Department of Pharmacology at Monash University, ... study to support the use of Cymerus™ mesenchymal stem ... Asthma is a chronic, long term lung condition ...
(Date:2/28/2017)... , February 28, 2017 News solutions for ... ... from 14 to 16 March, Materna will present ... show how seamless travel is a real benefit for passengers. ... biometrics to their passenger touch point solutions to take passengers through ...
Breaking Biology News(10 mins):
(Date:3/22/2017)... Florida , March 22, 2017 ... ... various cancer conditions are being pressured as of late due ... for cancer pain management has a dramatic impact on patient,s ... research and development activities for identifying new forms of opioid ...
(Date:3/22/2017)... 2017   Boston Biomedical , an industry leader ... target cancer stemness pathways, today announced its Board of ... Chief Executive Officer, effective April 24, 2017. ... , M.D., FACP, who has led Boston Biomedical since ... leadership, Boston Biomedical has grown from a "garage startup" ...
(Date:3/22/2017)... ... ... executive recruitment firm, Slone Partners, is proud to have been named a Top 50 ... Scanlon Media is one of the most respected life science publications in the United ... , “It is a great honor for Slone Partners to be part of this ...
(Date:3/22/2017)... ... March 21, 2017 , ... Proper glycosylation is critical ... desired increase and/or decrease in antibody-dependent cellular cytotoxicity or complement-dependent cytotoxicity, there is ... antibodies. , To meet this demand, the team at SCIEX has developed ...
Breaking Biology Technology: