of Africa, of

W. Allan provides examples, from various parts of Africa, of reductions in the number of animals ranging from 45 per cent to 97 1/2 per cent. 16 F. Barth,writing on pastoral nomads of South Persia, reports average losses of 50 per cent. 17 Hence, the larger the herd, the greater is the probability that in the case of emergency a sufficient number of animals will survive to provide the pastoralist with the means for his subsistence and for rebuilding his depleted herd. This preoccupation with security provides a sufficient explanation of his tendency to accumulate livestock. Moreover, it explains his consumption habits under normal conditions, which make him inclined to rely on dairy products rather than on meat, as well as his reI uctance to sell animals with breeding capabilities. 18

Security considerations may also be reflected in the composition of herds which favours animals able to cope best with a harsh environment.