These declines in turn fostered increased dependence on maize and its exchange and on domesticated turkey, which could be fed maize.

• 那些不利的趋势也许彼此会产生乘数效果，例如森林慢慢消失之后，很可能使狩猎变得更困难，一些重要的非驯化植物资源，如松子，也随之而去。