科学家发现，正在休息或吃草的鹿群和牛群倾向于按照地球磁感线排列。已知鸟、海龟和鲑鱼都可以在迁徙中利用磁场导航，而在哺乳动物中间，几种啮齿动物和一种蝙蝠也拥有磁罗盘。
Sabine Begall及其同事提出，他们的研究提供了证据表明大型哺乳动物也能感知地球磁场。这组科学家调查了Google Earth上全世界308个牧场和草原的8510头牛的照片，以及在捷克共和国的超过225个地点实地收集的2974只鹿的数据。他们的分析表明这些动物在吃草或休息的时候倾向于面朝磁北或磁南。由于不同地点的风的方向和阳光有很大的不同，这组科学家得出结论说地球磁场可能是一个共同因素，以某种方式影响着这些动物。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS published August 25, 2008, doi:10.1073/pnas.0803650105
Magnetic alignment in grazing and resting cattle and deer
Sabine Begall, Jaroslav Červený, Julia Neef, Oldřich Vojtčch, and Hynek Burda
We demonstrate by means of simple, noninvasive methods (analysis of satellite images, field observations, and measuring “deer beds” in snow) that domestic cattle (n = 8,510 in 308 pastures) across the globe, and grazing and resting red and roe deer (n = 2,974 at 241 localities), align their body axes in roughly a north–south direction. Direct observations of roe deer revealed that animals orient their heads northward when grazing or resting. Amazingly, this ubiquitous phenomenon does not seem to have been noticed by herdsmen, ranchers, or hunters. Because wind and light conditions could be excluded as a common denominator determining the body axis orientation, magnetic alignment is the most parsimonious explanation. To test the hypothesis that cattle orient their body axes along the field lines of the Earth's magnetic field, we analyzed the body orientation of cattle from localities with high magnetic declination. Here, magnetic north was a better predictor than geographic north. This study reveals the magnetic alignment in large mammals based on statistically sufficient sample sizes. Our findings open horizons for the study of magnetoreception in general and are of potential significance for applied ethology (husbandry, animal welfare). They challenge neuroscientists and biophysics to explain the proximate mechanisms.
