I can't believe nobody's mentioned Pavlov's experiments on Classical Conditioning.
Well now you have :) I loved learning about that in psychology class.
classical conditiong ftw
And you don't?
Dogs, like humans, are creatures of routine and habit though. They are trained by certain things having the same result every time. Ergo, it shouldn't surprise you that a dog's train of thought when hearing food related noises being "OMG FOOD"
But it's natural.
Not as underestimated as pigs though...
Pot bellied pigs make me giggle ^.^
I also find it amazing that my dog can associate "Stinky" with being an insult.