Are Cows Magnetic?

First posted on 08-26-2008

The results of a new study published by Sabine Begall and a group of colleagues from the University of Duisberg-Essen in Germany, demonstrate a preference by cattle to align themselves in a north-south manner.

After studying satellite photos from Google Earth to examine the habits of about 8500 cows in 308 sites around the world, Begall and her team concluded a preference for bovines to line up in a north to south configuration instead of just milling about in a random fashion. The team found a similar preference in deer and speculate that the animals may be sensing the Earth’s magnetic field.

This sense, called magnetoreception, has previously been documented in insects and birds but was a surprise for researchers studying larger mammals. “It is amazing that this ubiquitous conspicuous phenomenon apparently has remained unnoticed by herdsmen and hunters for thousands of years,” Begall wrote in her entry to Proceedings of the National Academy of Sciences1.

Scientists studying the satellite photos were very careful to avoid locations where other influences, like proximity to water and feeding areas, may have affected how the cows lined up.
By studying the details of alignment direction, Begall’s team was also able to discount theories such as cows aligning to maximize absorption of heat from the sun and lining up to cut wind profiles.

Begall’s team and other scientists did say a limitation of the research is that it was all based on correlations with no experimental manipulations to confirm the data. According to Nature.com, Begall may have an answer to this. Although it was not published, Begall’s team noticed that cows become misaligned near powerlines, where strong magnetic fields are present.