Another way that negrito populations may have enhanced their adaptive
capacity is to manipulate their environments, even to the extent of managing
resource use, so that they are not dependent solely on “wild” foods. Batek replant
tuber heads, continue to monitor the life of yam plants they have tended, and
may return to harvest new tubers when the plants have matured, a strategy that is
linguistically coded and conventional practice today (Lye 2004: 130–131). The
Agta of northeastern Luzon do so as well (Griffin 1984: 116). On occasion Batek
also have planted fruit trees on an opportunistic basis (Lye 2004: 123–144; see
also Hutterer 1983: 176). There is other evidence of hunter-gatherer resource
management in the literature, such as Western Penan management of the sago palm
(Eugeissona utilis) for sustained-yield purposes (Brosius 1991:143–144) and other
groups’ overall care in not damaging plants in the course of a harvest (on Lanoh,
see Dallos 2011: 42; on Semaq Beri, see Kuchikura 1987: 51). The point is that
patterns of forest structure and composition are sometimes direct outcomes of
intentional resource concentration and enrichment strategies [Hutterer 1983: 173;
Rambo 1979b: 62; Schebesta 1973 (1928): 83], which in turn bring hunter-gatherers
closer to self-sufficiency.