For critical analyses of Singer's and Regan's applications of their views to other areas, see:

• Agriculture: Gary Varner, "What's Wrong with Animal Byproducts?" in Journal of Agricultural and Environmental Ethics 7 (1994), pp. 7-17.

• Hunting: Gary Varner, "Can Animal Rights Activists Be Environmentalists?" chapter five of In Nature's Interests? Interests, Animal Rights and Environmental Ethics (Oxford University Press, 1998).