Donaldson and Kymlicka suggest that animals should be characterized through three categories, serving to determine the nature of the laws and politics that should protect those animals. Domesticated animals should be given a kind of adjusted co-citizenship in which their best interest and preferences would be taken into account. Donaldson and Kymlicka defend the end of their use, advocating for a vegan position, but they reject extinctionism with regards to those animals that are currently breed by humans. Wild animals should be granted sovereignty on their land enough so that they can sustain their way of living and prosper. Donaldson and Kymlicka support some moderate forms of intervention to reduce wild animal suffering, and they claim that more significant courses of action should be aiming at keeping wild animals able to lead their lives. "Liminal" animals, those that are not domesticated but live in urban, suburban, or industrial areas (such as mice, pigeons and insects), should be treated as denizens of human communities.