Featured Research

from universities, journals, and other organizations

The magnetic sense: Why powerlines confuse the internal compass of migrating birds

Date:
July 10, 2012
Source:
Ludwig-Maximilians-Universität München
Summary:
Migratory birds and fish use the Earth's magnetic field to find their way. Researchers have now identified cells with internal compass needles for the perception of the field – and can explain why high-tension cables perturb the magnetic orientation.

Migratory birds and fish use Earth's magnetic field to find their way. LMU researchers have now identified cells with internal compass needles for the perception of the field -- and can explain why high-tension cables perturb the magnetic orientation.

Although many animal species can sense the geomagnetic field and exploit it for spatial orientation, efforts to pinpoint the cells that detect the field and convert the information into nerve impulses have so far failed. "The field penetrates the whole organism, so such cells could be located almost anywhere, making them hard to identify," says LMU geophysicist Michael Winklhofer. Together with an international team, he has located magnetosensory cells in the olfactory epithelium of the trout.

The researchers first used enzymes to dissociate the sensory epithelium into single cells. The cell suspension was then stimulated with an artificial, rotating magnetic field. This approach enabled the team to identify and collect single magnetoresponsive cells, and characterize their properties in detail. Much to Winklhofer's surprise, the cells turned out to be more strongly magnetic than previously postulated -- a finding that explains the high sensitivity of the magnetic sense.

Magnetite crystals show the way

The cells sense the field by means of micrometer-sized inclusions composed of magnetic crystals, probably made of magnetite. The inclusions are coupled to the cell membrane, which is necessary to change the electrical potential across the membrane when the crystals realign in response to a change in the ambient magnetic field. "This explains why low-frequency magnetic fields generated by powerlines disrupt navigation relative to the geomagnetic field and may induce other physiological effects," says Winklhofer.

The new findings could lead to advances in the sphere of applied sciences, for example in the development of highly sensitive magnetometers. In addition, they raise the question of whether human cells are capable of forming magnetite and if so, how much. "If the answer to the question is yes," Winklhofer speculates, "intracellular magnetite would provide a concrete physiological substrate that could couple to so-called electrosmog."


Story Source:

The above story is based on materials provided by Ludwig-Maximilians-Universität München. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. H. K. Eder, H. Cadiou, A. Muhamad, P. A. McNaughton, J. L. Kirschvink, M. Winklhofer. Magnetic characterization of isolated candidate vertebrate magnetoreceptor cells. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1205653109

Cite This Page:

Ludwig-Maximilians-Universität München. "The magnetic sense: Why powerlines confuse the internal compass of migrating birds." ScienceDaily. ScienceDaily, 10 July 2012. <www.sciencedaily.com/releases/2012/07/120710120229.htm>.
Ludwig-Maximilians-Universität München. (2012, July 10). The magnetic sense: Why powerlines confuse the internal compass of migrating birds. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2012/07/120710120229.htm
Ludwig-Maximilians-Universität München. "The magnetic sense: Why powerlines confuse the internal compass of migrating birds." ScienceDaily. www.sciencedaily.com/releases/2012/07/120710120229.htm (accessed September 18, 2014).

Share This



More Earth & Climate News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) — Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) — A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) — Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) — Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
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:
from the past week

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