Abstract This study presents a mathematical model in which single beneficial mutation arises very large population that is subject to frequent deleterious mutations. The results suggest that, if the sexual, then mutations will have little effect on ultimate fate of mutation. However, most offspring are produced asexually, probability be lost from may greatly enhanced by Thus, sexual populations adapt much more quickly than where reproduction asexual. Some were using computer simulation...

A mathematical model is presented in which a single mutation can affect multiple phenotypic characters, each of subject to stabilizing selection. wide range mutations allowed, including ones that produce extremely small changes. The analysis shows that, when three or more characters are affected by mutation, optimal genetic sequence may become common. This result provides hypothesis explain the low levels variation and rates substitution observed at some loci.

Abstract In this study we consider a mathematical model of sexual population that lives in changing environment. We find low rate environmental change can produce very large increase genetic variability. This may help to explain the high levels heritability observed many natural populations. also asexuality and modest be damaging an asexual population, while leaving virtually unscathed. Furthermore, environment, advantages sexuality over much greater than suggested by most previous studies....

In this paper we present a mathematical model of mutation and selection that allows for the coexistence multiple alleles at locus with very small selective differences between alleles. The also determination fitness by loci. Models sort are biologically plausible. However, some previous attempts to construct similar models have assumed all mutations produce decrease in fitness, has led tendency average population members decline when numbers finite. our incorporate ideas R. A. Fisher, so...

A model is presented in which individuals who perform helping behavior can increase frequency from low initial levels a large population within interactions take place between randomly selected individuals. This accomplished without requiring extreme conditions. The uses payoff matrix that determines the consequences of each possible type interaction changes as function genetic constitution population. As result, may or not satisfy inequalities define prisoner's dilemma, formal game commonly...

Models of sexual haploids under kin selection are constructed. The trait altruism is transmitted vertically from parent to child, but not in a strictly genetic manner. Two systems considered: parent-to-offspring and sib-to-sib. In the former case it shown that even when Hamilton's conditions for success genetically determined met, genes increase transmission may invade population. With sib-to-sib altruism, such will always initially.

We present the results of a computer simulation model in which sexual population produces an asexual mutant. estimate probability that new lineage will go extinct. find whenever does not extinct is out–competed, and only individuals remain after sufficiently long period time has elapsed. call this type outcome takeover. Our suggest that, given repeated mutations to asexuality, takeover likely unstructured environment. However, if environment subdivided into demes are connected by migration,...

This paper presents a mathematical model of population in which multiple alleles at particular locus are maintained by frequency-dependent selection. The results suggest that, if the reproduces sexually, benefit conferred on beneficial mutations other loci will typically be much larger than asexual means. In part, this is true because, populations, can produce suboptimal distributions that subject to Another factor produces an advantage for sex have achieved high copy number may nevertheless...

A two-locus genetic model is studied in which one locus controls the tendency of individuals to act altruistically toward siblings and other mating habits females. It demonstrated that variation at altruism often sufficient induce an increase frequency genes cause females produce all their offspring with a single mate. This occurs because nonrandom associations develop between those affect female behavior. The results provide new explanation for evolution monogamy, they suggest previously...

The earliest organisms are thought to have had high mutation rates. It has been asserted that these rates would severely limited the information content of early genomes. This led a well-known “paradox” because, in contemporary organisms, mechanisms suppress mutations quite complex and substantial amount is required construct mechanisms. paradox arises because it not clear how efficient error-suppressing could evolved, thus allowed evolution at time when were too permit maintenance very...

Abstract A model is presented in which alleles at a number of loci combine to influence the value quantitative trait that subject stabilizing selection. Mutations can occur under consideration. Some these mutations will tend increase trait, while others decrease it. In contrast most previous models, we allow mean effect be nonzero. This means that, on average, have bias, such they either or trait. We find, unsurprisingly, biased mutation moves equilibrium direction bias. What more surprising...

This study presents a mathematical model that allows for some offspring to be dispersed at random, while others stay close their mothers. A single genetic locus is assumed control fertility, and this subject the occurrence of deleterious mutations. It shown that, equilibrium, frequency mutations in population inversely related rate dispersal. because dispersal leads enhanced competition among adults. The results also show sexual reproduction can lead decrease equilibrium reason relationship...

This study presents a mathematical model in which the fitness of an individual depends on individual's genotype (individual effects) and genotypes other members local group (group effects). The findings suggest that, if phenotypes are result complex interactions between genes at different loci, then fitness-enhancing effects may become common sexual populations. spread is facilitated when environmental conditions sometimes deteriorate temporarily. so even with highest also tend to have...

Phase III of Sewall Wright's shifting-balance process involves the spread a superior genotype throughout structured population. However, number authors have suggested that this sort adaptive change is unlikely under biologically plausible conditions. We studied relevant mathematical models, and results suggest concerns about phase are justified, but only if environmental conditions stable. If in way alters species range, then can be effective, leading to an enhancement adaptedness