Evolution neutral

Gillespie, J. H. (1994). Alternatives to the neutral theory. In Non-Neutral Evolution Theories and Molecular Data. (B. Golding, ed.) pp. 1-17. Chapman Hall, New York. 

Puri and collaborators (3d, 59) found that the amount of CO2 given off on heating to 1200° was always equivalent to the Ba(OH)2 or NaOH neutralization. Evolution of COj was complete between 750 and 900°. Samples oxidized in liquid medium evolved more COg in relation to CO on heating than did samples treated with oxygen (3d, 55). Puri and Bansal (59) suggested that the neutralization of alkali was caused by carbon dioxide chemisorbed on the carbon surface ( COg complex ). If carboxyl groups were responsible, 1 mole of COg should be formed for each equivalent of alkali consumed. The author of this article thinks, as will be shown below, that very likely carboxyl groups of different environment are responsible for bicarbonate and carbonate neutralization as well as COg evolution. 

In population genetics there is experimental evidence that many mutations are neutral, which is consistent with Kimura s theory of neutral evolution [19]. Kimura s theory is based on a neutrality condition, that is, on the assumption that the natality and mortality functions as well as the transport (migration) coefficients are the same for the main population as well as for the mutants. For neutral mutations the nonlinear reaction-diffusion equations for the spreading of a mutation within a growing population which is expanding in space have a... 

Neutral evolution is based on the hypothesis that most mutations made on the molecular level do not alter the fitness of an organism (Kimura, 1983 Kimura, 1991). This is in contrast to adaptive, or Darwinian, evolution, which asserts that mutational changes that survive selection usually have a beneficial effect. There is empirical evidence supporting both theories (King and Jukes, 1969 Kimura, 1991 Eanes et al., 1993 Hall, 1998). Recent efforts have focused on the relationship between neutral and adaptive evolution and insight has been provided into the mechanisms by which neutral evolution can drive adaptation. The neutral structure of a fitness landscape can aid the evolutionary search. Adaptive... 

Most of the studies of the ability of neutral evolution to discover new phenotypes have been carried out on RNA secondary structure models. Here, the neutral network is defined as a connected region of sequence... 

Van Nimwegen and Crutchfield (1999a) have constructed a theory for the optimization of evolutionary searches involving epochal dynamics. They showed that the destabilization of the epochs due to fluctuations in the finite population occurs near the optimal mutation rate and population size. Under these conditions, the epoch time is only constrained by the diffusion of the population to a neutral network boundary. Often the optimal parameters are very close to the region in which destabilization is an important effect. This emphasizes that, to utilize neutral evolution, it is important to tune the evolutionary parameters (such as mutation rate and population size) so that the time spent in an epoch is minimized without destabilizing the search. 

The benefit of neutrality has yet to be captured with in vitro protein evolution. Neutral theory predicts the punctuated emergence of novel structure and function, however, with current methods, the required time scale is not feasible. Utilizing neutral evolution to accelerate the discovery of new functional and structural solutions requires a theory that predicts the behavior of mutational pathways between networks. Because the transition from neutral to adaptive evolution requires a multi-mutational switch, increasing the mutation rate decreases the time required for a punctuated change to occur. By limiting the search to... 

Two or more genotypes are neutral in evolution when the selection constraint is unable to distinguish between them. Early sequence comparison data [6] apparently confirmed Motoo Kimura s idea of neutral drift in population genetics [5]. Accordingly, many different genotypes could give rise to the same phenotype, and depending on the conditions, different phenotypes can share the same fitness value. Direct evidence for neutral evolution under controlled conditions came only two years ago Se-... 

The ratio of nonsynonymous to synonymous substitutions in a protein-coding gene may reflect the relative influence of positive or purifying selection and neutral evolution. Therefore, protein sequence information is supplemented by an analysis of synonymous and nonsynonymous base substitutions in the DNA sequences. The calculations are performed by means of the program Syn-SCAN (hivdb.stanford.edu/pages/synscan.html) (15) that adopts a method by Nei and Gojobori (16). The output list includes 10 statistical parameters (see Note 2) and in particular the measure (Sd - Nd)/(Sd + Nd), where Sd and Na. stand for the observed synonymous and nonsynonymous substitutions, respectively. 

Figure 2. Empirical versus predicted relationships between heterozygosity at enzyme loci (He) and population size (N) in Dolichopoda populations. Experimental values are plotted against theoretical curves calculated at different mutation rates (10

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