The use of whakapapa by New Zealand Maori is most commonly understood in reference to human descent lines and relationships, where it functions as a family tree or genealogy. But it also refers to an epistemological framework in which perceived patterns and relationships in nature are located. These nonhuman whakapapa contain information concerning an organism's theorized origins from supernatural beings, inferred descent lines, and morphological and ecological relationships. In this context whakapapa appear to function at one level as a "folk taxonomy," in which morphology, utility, and cultural considerations all play an important role. Such whakapapa also function as ecosystem maps of culturally important resources. More information and meaning is provided by accompanying narratives, which contain explanations for why things came to be the way they are, as well as moral guidelines for correct conduct.

Renewed interest in the whakapapa of plants and animals has arisen from concerns raised by Maori in regard to genetic modification, particularly the transfer of genes between different species, as this concept is frequently invoked by those who oppose transgenic biotechnology. Informed dialogue on this subject requires an understanding of the structure and function of nonhuman as well as human whakapapa and their underlying rationale, as well as the nature of the relationships among the things included in nonhuman whakapapa. Of additional interest and relevance is the relationship of whakapapa to modern scientific concepts of taxonomy based on phylogeny and the species concept.

In this paper we describe and interpret the whakapapa of an important food plant, the sweet potato or kumara, in terms of its apparent functions and underlying rationale. We also discuss how the whakapapa and its associated narratives might contribute to the current debate on genetically modified organisms in New Zealand.