We will use the life table for Phlox (Table 8.4) as the starting point for our analysis. The model calculates the value of $V_x$ at each age from the value of $l_x$ in the life table and plots it as a function of age. Explore the ways that the values of $b_x$ and $l_x$ affect the graph with the following exercises. After each, examine the change in the values of $V_x$ and the nature of the $V_x$ curves.

1. Increase or decrease the overall reproductive output at each age
2. Change the pattern of reproductive output over the course of the lifespan
3. Increase or decrease the survival at each age