Magnetic alignment in warthogs Phacochoerus africanus and wild boars Sus scrofa

Magnetic alignment (MA) results from the preference of animals to align themselves along the field lines of the geomagnetic field, a behavioural expression of a magnetic sense. MA is well documented for ruminants and might demonstrate a general magnetic sensory ability among artiodactyls. We measured body-axis alignment in 1614 foraging or resting wild boars Sus scrofa, 1849 wild boar beds, and 1347 warthogs Phacochoerus africanus, and found a highly significant north-south preference. The magnetic field was the only common denominator of all observations. Thus, we provide the first data suggesting a magnetic sense in the Suidae.