An important structuring principle to pastoralist exchange is that herding systems are not economically independent because humans must consume a sufficient diversity of major food groups for nutritional reasons; a condition known as non-autarkic (Khazanov 1984;Nielsen 2000). Depending on available wild plants, herders may acquire a portion of their non-animal products from gathering activities but the more common solutions involve a mixed agro-pastoral strategy or articulation with agriculturalists. Furthermore, herders with animals capable of bearing loads are the natural agents for facilitating this articulation with agriculturalists (Browman 1990;Flores Ochoa 1968). Thus, exchange relations are a basic necessity for dedicated herders. For herders with cargo animals, the transport of exchange goods in some capacity was likely a regular feature of pastoral household economies, and to become more common and less laborious in terms of quantity of goods exchanged due to assistance of cargo animals. As pastoralist households are not autarkic, due to the need for non-animal foods on a regular basis, households usually have cargo animals as part of their herd and relatively brisk exchange networks are likely to develop between households without the need for elites, administrative oversight or investment from super-family organization.