However, when this animal leaps it launches into a graceful glide, spreading wide the enormous membrane that spans its legs and tail to cover distances of up to 150m. So, when Greg Byrnes and his colleague Andrew Spence from the University of California, Berkeley, USA, were looking around for a mammal to carry the accelerometer/radio transmitter backpacks that the duo designed to track animals in the field, the colugo was an obvious choice.
'They are a large glider and it was an opportunity to learn about an animal that we didn't know much about,' says Byrnes. Admitting that they were initially interested in the natural history of these charismatic creatures, Byrnes realised that they could use the information gathered to find out about the cost of the colugo's gliding lifestyle. Flying to Singapore, Byrnes teamed up with Norman Lim to track the gliding mammals and the team discovered that instead of saving energy, colugos glide to save time. They publish this discovery in The Journal of Experimental Biology at http://jeb.biologists.org/content/214/16/2690.abstract
Describing how some of the nocturnal colugos roost low in the forest, Byrnes was able to capture six of the mammals and glue the accelerometer packs to their backs before allowing them to scurry back up their trees for their first glide of the night. Explaining that the data loggers were able to collect data for 3 days, Byrnes and Lim tracked the animals until the data loggers eventually fell off and they were able to retrieve them several weeks later.
Back in Berkeley, Byrnes, Spence and Thomas Libby had the unenviable task of managing the colossal amount of data collected: 'We were sampling at 100Hz for days,' explains Byrnes. According to Byrnes, there is a distinctive acceleration profile when they glide. 'What you see is the leap and the landing when there is this sweeping acceleration, so it's easy to pick out their glides,' he says. Eventually, the trio converted each animal's acceleration traces into velocities – as they scaled trees and glided – and then they calculated the distances that the animals covered.
Analysing the glide trajectories, the team realised that the colugos only climb a relatively small height to achieve their lengthy shallow glides. 'The average was 8 m for an animal that is gliding 30m,' says Byrnes. But how much energy were they using to cover that distance?
Basing their calculations on the amount of energy used by small climbing primates – close relatives of the colugo – the trio calculated the energy used by a colugo ascending a tree to initiate a glide. Then they calculated the amount of energy that the animals would use if they had clambered through the canopy to cover the glide distance and were amazed to see that instead of saving energy, the colugos were using 1.5 times more energy. 'This was a surprise, as the dogma has always been that gliding is cheaper,' says Byrnes.
However, one thing was clear: gliding was faster. 'If you watch the animals move through the trees they move pretty slowly,' says Byrnes, 'But they can go 10 times as fast and cover long distances gliding so they can spend more time foraging,' he explains. Gliding could also protect colugos from dangerous predators and reduce the risks of climbing on spindly branches, so it could be more of a long-term benefit than simply saving energy
IF REPORTING ON THIS STORY, PLEASE MENTION THE JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO: http://jeb.biologists.org
REFERENCE: Byrnes, G., Libby, T., Lim, N. T.-L. and Spence, A. J. (2011). Gliding saves time but not energy in Malayan colugos. J. Exp. Biol. 214, 2690-2696.
This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required, and if reporting online a link to jeb.biologists.com is also required. The story posted here is COPYRIGHTED. Therefore advance permission is required before any and every reproduction of each article in full. PLEASE CONTACT firstname.lastname@example.org
Nanobot pumps destroy nerve agents
21.08.2018 | American Chemical Society
How do muscles know what time it is?
21.08.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.
The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
21.08.2018 | Medical Engineering
21.08.2018 | Physics and Astronomy
21.08.2018 | Power and Electrical Engineering