Computer simulations on the sympatric speciation modes for the Midas cichlid species complex

Cichlid fishes are one of the best model system for the study of evolution of the species. Inspired by them, in this paper we simulated the splitting of a single species into two separate ones via random mutations, with both populations living together in sympatry, sharing the same habitat. We study the ecological, mating and genetic conditions needed to reproduce the polychromatism and polymorphism of three species of the Midas Cichlid species complex. Our results show two scenarios for the A. Citrinellus speciation process, one with and the other without disruptive natural selection. 
In the first scenario, the ecological and genetic conditions are sufficient to create two new species, while in the second the mating and genetic conditions must be synchronized in order to control the velocity of genetic drift

Quantum Noise in the Collective Abstraction Reaction A+B 2→_2\to AB+B

We demonstrate theoretically that the collective abstraction reaction A+B$_2 \to$ AB+B can be realized efficiently with degenerate bosonic or fermionic matter waves. We show that this is dominated by quantum fluctuations, which are critical in triggering its initial stages with the appearance of macroscopic non-classical correlations of the atomic and molecular fields as a result. This study opens up a promising new regime of quantum degenerate matter-wave chemistry.Comment: 4 pages, 3 figures, publishe

Simulating inbreeding depression through the mutation accumulation theory.

Using the Penna model for biological aging, which is based on the mutation accumulation theory, we show that the number of homozygous loci corresponding to deleterious mutations is higher in small populations than in large ones. This decrease of heterozygosity may drive small populations to extinction even when no drastic change of the environment occurs

Monte Carlo simulation of inherited longevity.

Within the Penna model of biological ageing, we show that longevity is heritable, for both sexual and asexual reproduction

Self-organisation of female menopause in populations with child-care and reproductive risk.

In this paper, by using a computer model for the evolution of age-structured populations, we show that in a sexual population subject to: (i) senescence, (ii) age-increasing reproductive risks, and (iii) long juvenile dependence, menopause arises spontaneously, in order to guarantee the survival of the offspring

Simulated self-organization of death by inherited mutations

ABSTRACT An agent-based computer simulation of death by inheritable mutations in a changing environment shows a maximal population, or avoids extinction, at some intermediate mutation rate of the individuals. Our results indicate that death seems needed to allow for evolution of the fittest, as required by a changing environment