Being delicious is a great adaptation though, although it dooms individuals to a premature death, it has secured the future of the species. As long as humans are around, pigs and cows will be as well.

If we weren't so keen on describing things involving humans as "unnatural", I think the relationship between humans and livestock animals would generally be seen as symbiotic (much like ants who farm fungus).

I hear humans taste like pork. Cannabalism hasn't really taken off though.