The wild boar is the wild ancestor of the domestic pig. It is native in woodlands across much of Central Europe, the Mediterranean Region (including North Africa’s Atlas Mountains) and much of Asia as far south as Indonesia, and has been widely introduced elsewhere
Wild boars live in groups called sounders. Sounders typically contain around 20 animals, but groups of over 50 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 a breeding cycle, two to three per year, and are usually found alone. Birth, called farrowing, usually occurs in a secluded area away from the sounder; a litter will typically contain eight piglets, but up to 13 have been known.
The animals are usually nocturnal, foraging from dusk until dawn but with resting periods during both night and day. They eat almost anything they come across, including nuts, berries, carrion, roots, tubers, refuse, insects, small reptiles—even young deer and lambs.
Boars are the only hoofed animals known to dig burrows, a habit which can be explained by the fact that they are the only known mammals lacking brown adipose tissue. Therefore, they need to find other ways to protect themselves from the cold. For the same reason, piglets often shiver to produce heat themselves.
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