Population Ecology in an Agrarian Society.

<p>Components within the dashed rectangle make up the model itself; solid arrows depict the causal relationships that link them. Model parameters, those that must be set and can be manipulated for analytical purposes, are shown outside the dashed box. Dotted arrows show their point of operation in the logical structure of the model. Time is indexed implicitly in all model terms; <i>x</i> indexes age.