it is not just farming land that is valuable, sometimes there are good fishing spots and etc in scarce regions. However those are far rarer situations and usually there is plenty of food for everyone, but hard times also happen and then most animals and humans practice mutual aid. There is a good book about it, by Kropotkin, called Mutual aid. It isn’t long, I listened to the audio book.
Yes, there is a good book about it, called “Mutual Aid: A Factor of Evolution”.