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Cows seem to know which way is north
(Agencies)
Updated: 2008-08-26 11:06 However Lohmann, who was not part of the research team, cautioned that "the study is based entirely on correlations. To demonstrate conclusively that cattle have a magnetic sense, some kind of experimental manipulation will eventually be needed." Joseph L. Kirschvink of the California Institute of Technology said he wondered if fences around the pastures could affect cattle orientation. Passive alignment of animals to magnetic fields has been reported in honeybees and termites, he noted. It requires some type of special sensory organ to detect the magnetic field. "If they have evidence suggesting that mammals are using magnetic fields to orient their movements, this is very cool," said Mark A. Willis, an associate professor of biomedical sciences at Case Western Reserve University in Cleveland. Willis, who was not part of the research team, added, "We have only in the last few years begun to understand the mechanisms underlying magnetic field orientation in birds and other smaller animals." Indeed, it's small animals that led to this study, Begall explained. They were researching the magnetic field effect on African mole-rats. "At one point last year the question came up whether large animals could also sense the Earth's magnetic field or not. But of course, it is difficult, or maybe impossible, to do these studies in the lab," she said. "So, the idea arose to look for other large mammals like cattle, and Hynek Burda was fascinated when he recognized that cattle could be found on Google Earth satellite images." With satellite images they could tell the north-south orientation of the animals, but not whether an individual cow was facing north or south. You have to get closer to tell which end is which. Now the researchers are moving on to study sheep, goats, horses, wild boar and some further deer species, Begall added. The current study said red and roe deer also were found to orient in a north-south direction when grazing and resting, but unlike the worldwide cattle study, the deer portion was limited to the Czech Republic. |
