Kubo people of Papua New Guinea sometimes grew Dioscorea yams in mounds of forest litter that were made as egg-incubation sites by birds (Megapodiidae). The small yam plots were included within larger banana gardens and, in the latter, it was yams, not bananas, that took precedence in the gardening decisions of people. The technique would be viable in the absence of a larger garden. It is interpreted as an expression of an ancient pattern of small-scale plant domestication.
One of the ways we can begin solving our global environmental problems is by growing our own food. This puts us back in touch with the cycles of life and death -- from plant to food to offal to decay to soil to plant again. Might this be the underlying mission of sustainable agriculture?