Evans-Pritchard depicts Nuer culture as being shaped by environmental and ecological concerns, chiefly with regard to their pastoral livelihood of raising cattle. While they cultivate crops on a small scale and engage in other food-gathering activities like fishing, cattle-raising is their central concern: “at their heart they are herdsmen, and the only labour in which they delight is care of cattle. […] Cattle are their dearest possession […]. Most their social activities concern cattle” (16). The necessity of cooperation in the process of raising herds of cattle influences the structure of Nuer society, dictating that families must band together into villages in order to build a common kraal and to protect their pasturage. Even kinship relations are usually expressed in terms of cattle, since herds are owned by families rather than being regarded as personal property. Further, the transfer of cattle between families is an essential element of marriage rituals, and both men and women are customarily addressed with names derived from the identities of their favorite cows and oxes: “Since cattle are a Nuer’s most cherished possession, being an essential food-supply and the most important social asset, it is easy to understand why they play a foremost part in ritual” (18).