We show that the problem of existence of a mitochondrial Eve can be understood as an application of the Galton–Watson process and presents interesting analogies with critical phenomena in Statistical Mechanics. In the approximation of small survival probability, and assuming limited progeny,...

We study the phenomenon of internal avalanching within the context of recently proposed “Tetris” lattice models for granular media. We consider a packing of particles subjected to two different dynamics. In the first case, we arrest the system at different instances during an “aging”...

Two discrete-time deterministic epidemic models are analysed numerically in order to determine their properties and evolutions. One of the models is formulated as discrete-time approximation of a corresponding continuous-time model. Restrictive assumptions are made on the parameters of the...

We investigate a population of individuals who play the Rock–Paper–Scissors (RPS) game. The players choose strategies not only by optimizing their payoffs, but also taking into account the popularity of the strategies. For the standard RPS game, we find an asymptotically stable polymorphism...

Since its original proposal in 1995, the bit-string model has been used to study diverse aspects and situations concerning the evolutionary theory of aging. In this work, we follow a different path: we show two examples where simple age-structured population models are able of making predictions...

Rotational flow is often observed in lotic ecosystems, such as streams and rivers. For example, when an obstacle interrupts water flowing in a stream, energy dissipation and momentum transfer can result in the formation of rotational flow, or a vortex. In this study, I examined how rotational...

Classical models for competition between two species usually predict exclusion or divergent evolution of resource exploitation. However, recent experimental data show that coexistence is possible for very similar species competing for the same resources without niche partition. Motivated by this...

We consider the dynamics of a biological population described by the Fisher–Kolmogorov–Petrovskii–Piskunov (FKPP) equation in the case where the spatial domain consists of alternating favorable and adverse patches whose sizes are distributed randomly. For the one-dimensional case we define...

We analyze the transient dynamics of an ecosystem described by generalized Lotka–Volterra equations in the presence of a multiplicative noise and a random interaction parameter between the species. We consider specifically three cases: (i) two competing species, (ii) three interacting species...

The effects of periodic environmental fluctuations on the adaptive behavior and on the survival chance of a population of individuals are investigated as a function of both the genotypes carried, i.e., haploid or diploid. Only extreme and exogenous changes have been taken into account in order...