Early Warning Signals for Critical Transitions: A Generalized Modeling Approach
Figure 2
Early warning signal for a single population with Allee effect.
(a) Population time series (solid line, left axis, in relative units) and yearly births (circles, right axis) generated by the simulation model described in Text S1. The vertical dashed line indicates the time of the bifurcation. Parameters were ,
,
and
. The simulation was started at
to allow for the decay of transient responses. (b) Eigenvalues estimated from the sampled data indicated with markers in (a), using the procedure described in the text. The eigenvalue was always real.