They know the face that feeds them

PIGS may be able to tell people apart by their faces. Hajime Tanida of
Hiroshima University in Japan trained pigs to approach a person wearing
overalls, gloves and boots by rewarding them with food. Individual pigs were
then given the choice of approaching the feeder or an identically dressed
person, when both sat behind waist-level screens. Even if the researchers’
scents were masked with perfume, or they partially hid their faces, the pigs
still approached the original feeder (Applied Animal Behaviour Science, vol 73,
p 45). “Visual cues are very important for them,” says Tanida. “They are smart
and…