Figure 4

Bifurcation diagram varying β ₁ . The bifurcation diagram of $\bar{T}$ varying β₁, showing the attracting regions. With respect to the coordinates of small equilibrium point ${\bar{Q}}_{<}^{*}$ for all β₁, the trivial ${\bar{Q}}^0$ is attractor for initial conditions in a very small region I (and Ia). Initial conditions in regions II and III are attracted to ${\bar{Q}}_{>}^{*}$ for ${\beta }_1<{\beta }_1^c$, and initial conditions in regions IIa and IIIa are attracted to ${\bar{Q}}_{>}^c$ for ${\beta }_1\ge {\beta }_1^c$. The scales of vertical and horizontal axes must be multiplied by the factors shown in the legends to obtain the actual values.