Human domestication dog, pig, sheep, arrogant, , the animal such as chicken is to obtain food source on one hand, but also not be for food source completely, still have other function.
Inchoate mankind is in primitive society period is clannish tribe, at that time the social production of people basically is give priority to with food. So the woman at that time pursues picked trade, male people catchs the protein that catchs a beast to obtain carnivorous to offer human body place to need! But the mankind is in the Stone Age that still cannot make advanced tool, the successful rate that catchs hunt is very low, often be to need to rely on to fight with the beast casualties rate is very high, gradually human civilization develops to think always cannot be such.
It is OK that the people of primitive society discovers some beasts are the course comes artificially of domestication, breed after domestication need not risk danger to catch hunt again (the one great progress that this is human civilization) .
Domestic pig comes by boar domestication, the sheep is by wild goat domestication, wild pheasant domestication comes to chicken, these a few kinds basically are carnivorous be regardinged as; And the ox comes by bison domestication, the earliest also be carnivorous be regardinged as, but discover the ox is to be able to be engaged in agriculture producing later, use the ox at agricultural domain not to regard as carnivorous origin; And the dog comes by wolf domestication, basically be the cautionary public order that is used at primitive society, prevent tribe of beast sneak attack; The horse is use at vehicle by what bronco domestication comes.
Because this is in inchoate human civilization phylogeny,every kinds of animal is holding the position of different tool can, onefold saying is it is food source not accurate.