A crash course in changing the world.
To be more specific, a chicken can be feed with grass, seeds, worms, insects, vegetable waste (peelings from potatoes, appels, etc). This animal is neither stupid nor dirty, and if you have only one chicken, you can easily keep it at home like a pet, it will still lay eggs.
I have read that chicken came initially from tropical zones, but some grow in cold country too (like Canada, with -35°celsius winters).
I add that the eggs are an excellent source of food, very rich, that can be eaten alone, or use to cook :)