Featured Research

from universities, journals, and other organizations

How 'Sandfish' Swim: Could Help Materials Handling And Process Technology Specialists

Date:
October 14, 2008
Source:
Public Library of Science
Summary:
It moves as quickly in sand as a fish moves through water, which is why this lizard, a species of skink (Scincus scincus) that grows to about 15 cm long and lives in the deserts of North Africa and the Near East, is commonly known by the name "sandfish."

Morphology of a sandfish. (A) A living adult sandfish in the hand of the experimenter. (B) top-view (C) side-view of a 3D-reconstruction of a fixed sandfish. The spatula-shaped snout, the streamlined body shape, the smooth integument, long limbs as well as long and fringed digits can be seen representing typical adaptations to live in lose sand.
Credit: Baumgartner et al., DOI: 10.1371/journal.pone.0003309

It moves as quickly in sand as a fish moves through water, which is why this lizard, a species of skink (Scincus scincus) that grows to about 15 cm long and lives in the deserts of North Africa and the Near East, is commonly known by the name "sandfish."

Although it looks fairly unremarkable, this desert animal has a thing or two to teach materials-handling and process-technology specialists,as it spends most of its time below the surface of the sand and moves through its element extremely efficiently,and scientists hope to apply the insights they gain from nature to improve industrial technologies for the handling of granular materials.

Whether it's gravel, sand or flour, optimising the technology for handling such materials could significantly reduce energy and maintenance costs for businesses such as quarries and industrial bakeries in the future.

In a new article published in the journal PLoS One, Prof. Werner Baumgartner and colleagues from the Department of Cellular Neurobionics at RWTH Aachen used an MRI scanner to observe the sandfish as it "swims" through the sand.

"We took a round container that would fit snugly into the MRI and filled it with sand," says Prof. BaumgartnerBaumgartner.The project, which was carried out in collaboration with researchers from the University of Würzburg and Museum König in Bonn, has provided a visual record of the animal's movements in the sand as viewed from above and from the side.

The scientists found the results highly surprising:until now, it was thought that the sandfish pulled its legs in against its body, but the experiments revealed that it actually moves its legs back and forth in a fixed pattern."This seems illogical at first, because sand provides resistance," says Baumgartner."But we found out that its leg movements are very well coordinated with the wriggling of its body."

It turns out that the sandfish moves in a way very similar to the crawl stroke in swimming.When the animal moves its head or upper body to the left, for example, it leaves a gap and thus an area of looser, less dense sand to its rightthat allows the animal to move its front right leg forward with little effort.Conversely, when the sandfish moves its upper body to the right a moment later, the sand on that side is compressed; this compact sand provides a stable basis from which to push off its front right leg.The time displaced-movements of the lizard's legs according to this principle add up to a very efficient and extremely rapid form of locomotion.

Interestingly, the biologists discovered that the sandfish always moves through sand at the same frequency."The lizard's winding movements produce vibrations in the sand," explains Baumgartner."Our experiments showed that these vibrations have a consistent frequency of 3 hertz (three motions per second)."

The scientists hypothesized that this frequency allows the animal to move forward with the least amount of energy,and subsequent tests confirmed their assumption.They did so by building an aluminium model of a sandfish with a motor and having it move back and forth through the sand at different frequencies.They found that the force required to move the aluminium sandfish forward was lowest at exactly 3 Hz, as that was when the sand surrounding its body was loosest.

"The sandfish adapted to moving efficiently through granular material over millions of years," says the Aachen-based neurobionics expert.Scientists are increasingly applying insights gained from nature to a wide range of innovative technological uses."For example, we can use mathematical and computer-based models to calculate the ideal frequency for transporting all different kinds of granular materials," says Baumgartner.

Thus materials-handling and process-technology engineers are not the only ones who can learn from the sandfish;structural engineers stand to benefit, as well.For instance, by using the optimal frequency for the job, they will now be able to sink ground anchors into granular soil layers more efficiently, which will save both energy and money.


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Baumgartner et al. Investigating the Locomotion of the Sandfish in Desert Sand Using NMR-Imaging. PLoS ONE, 2008; 3 (10): e3309 DOI: 10.1371/journal.pone.0003309

Cite This Page:

Public Library of Science. "How 'Sandfish' Swim: Could Help Materials Handling And Process Technology Specialists." ScienceDaily. ScienceDaily, 14 October 2008. <www.sciencedaily.com/releases/2008/10/081003122547.htm>.
Public Library of Science. (2008, October 14). How 'Sandfish' Swim: Could Help Materials Handling And Process Technology Specialists. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2008/10/081003122547.htm
Public Library of Science. "How 'Sandfish' Swim: Could Help Materials Handling And Process Technology Specialists." ScienceDaily. www.sciencedaily.com/releases/2008/10/081003122547.htm (accessed October 20, 2014).

Share This



More Earth & Climate News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) — Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
Powered by NewsLook.com
Beijing Marathon Runners Brave Hazardous Air Pollution

Beijing Marathon Runners Brave Hazardous Air Pollution

AFP (Oct. 19, 2014) — Tens of thousands of runners battled thick smog at the Beijing Marathon on Sunday, with some donning masks as the levels of PM2.5 small pollutant particles soared to 16 times the maximum recommended level. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

Newsy (Oct. 19, 2014) — With Sweden on the look-out for a suspected Russian sub, a lot of people are talking about the Cold War, but is it an apt comparison? Video provided by Newsy
Powered by NewsLook.com
Orca Pod Spotted in Seattle's Puget Sound

Orca Pod Spotted in Seattle's Puget Sound

Reuters - US Online Video (Oct. 18, 2014) — A pod of killer whales was found swimming off Vashon Island in Washington state. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins