Ingo Arndt / Wild boar in snow {Sus scrofa} Germany

Ingo Arndt / Wild boar in snow {Sus scrofa} Germany captive

Fabrice Cahez / Three wild Boar (Sus scrofa) crossing snow covered field, Vosges, France, January

Ernie Janes / Two large white piglets (Sus scrofa domestica) at 3 weeks in sty, UK

Edwin Giesbers / Red river hog (Potamochoerus porcus) close up of head, captive

Nick Turner / Gloucester old spot domestic pig (Sus scrofa domestica) head portrait with ring through snout and ears covering eyes, UK.

Nick Turner / Freerange Gloucester old spot domestic pig (Sus scrofa domestica) portrait with ears covering eyes, UK.

Nick Turner / Gloucester old spot piglets (Sus scrofa domestica) suckling at the Cotswold Farm Show, Cirencester, UK, July 2008.

Nick Turner / Gloucester old spot piglets (Sus scrofa domestica) suckling at the Cotswold Farm Show, Cirencester, UK, July 2008.

LYNN M. STONE / Mixed-breed piglet in straw, Maple Park, Illinois, USA

LYNN M. STONE / Mixed-breed piglet in wooden box with sunflowers, Maple Park, Illinois, USA

LYNN M. STONE / Sleeping mixed-breed piglet in straw, Maple Park, Illinois, USA