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Note added at 36 mins (2011-02-24 11:11:43 GMT)
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...Some foragers in East Africa and Western North America are known to have periodically regenerated the productivity of their environments by intentionally burning grasslands and sparse woodlands. This encouraged the growth of tender new vegetation which attracted game animals. It is likely that controlled burns of this sort were used by foragers elsewhere in the world as well.

Foragers rely mainly on their own muscle power in carrying out their subsistence tasks. Most labor is done individually or in small groups of relatives and friends. There is an almost a complete absence of occupational choice. Every man is primarily a hunter of animals and every woman is mainly a gatherer of plants. Economic roles are mostly based on gender and age. However, it is not unusual for some tasks to be performed by either men or women. Gathering of firewood as well as collecting mollusks, insects, and other small game for food are often non-gender specific activities...

http://anthro.palomar.edu/subsistence/sub_2.htm