2026/06/03 by Marcelo A. Pires, José S. Andrade, Hans J. Herrmann · 1 voice
Physics and Astronomy · Biochemistry, Genetics and Molecular Biology · #nlin.CD #physics.comp-ph #physics.soc-ph #q-bio.PE
We present a novel nonlinear dynamical model, the generalized Allee-logistic (GAL) map given by xt+1 = r xt (1 - xt) G(xt) where G(xt) = m (xt - h) + 1 - m incorporates the Allee effect with magnitude m and threshold h. The case m = 0 yields the logistic map with a continuous transition to extinction. Conversely, m = 1 recovers a previously studied model that undergoes only a discontinuous extinction-to-active transition. Between these extremes, the GAL map exhibits nontrivial phenomena, including tricriticality with a closed-form expression for the tricritical point and a universal crossover function. Under a small external input, we verify Widom-like relations. We also note that the Allee effect disfavors the onset of chaos. Our work establishes additional bridges between analytically tractable chaotic maps, nonequilibrium tricriticality, and Allee effects.