One characteristic by which domestic breed and wild animals are differentiated is coats. Wild animals almost always have thick, short bristly coats ranging in colour from brown through grey to black. A prominent ridge of hair matching the spine is also common. The tail is usually short and straight. Wild animals tend also to have longer legs that domestic breeds and a longer and narrower head and snout. European adult males can be up to 200kg and have both upper and lower tusks, females do not have tusks and are around a third smaller on average.
Wild boars live in groups called sounders. Containing around twenty animals, but gruops of over fifty have been seen. In a typical sounder there are two or three sows and their offspring, adult males are not part of the sounder outside of the autumnal breeding season and are usually fond alone. Birth, called farrowing, usually occurs in the spring and a litter will typically contain five piglets but up to thirteen is known.
The animals are usually nocturnal, foraging from dusk until dawn but with resting periods both during the night and the day.
Wild boars are large but rarely dangerous. They are hunted either for food or because they are damaging crops. One of the Twelve Labors of Heracles was hunting a wild boar.