We were surprised to also observe a fourth type of trajectory where sterile strains rise to some frequency and remain there for hundreds of generations, suggesting the action of frequency-dependent selection.
In addition, the high randomness and variation of wind power lead to frequent action of traditional frequency regulation units resulting in increased abrasion of the mechanical devices and reduced operating life.
However, under negative frequency-dependent selection, or under the joint action of negative frequency-dependent selection and heterozygote advantage, distributions of allele frequencies were less predictable: the majority of distributions were indistinguishable from neutral expectations, while the remaining runs resulted in either more even or more skewed distributions than under neutrality.
The aim of our study was to compare frequency distributions of MHC alleles in simulations that mimicked host-parasite coevolution under three scenarios: 1) simultaneous action of negative frequency-dependent selection and heterozygote advantage; 2) heterozygote advantage without negative frequency-dependent selection; and 3) negative frequency-dependent selection without heterozygote advantage.
In our model, we compared three scenarios: 1) simultaneous action of negative frequency-dependent selection and heterozygote advantage; 2) heterozygote advantage without negative frequency-dependent selection; and 3) negative frequency-dependent selection without heterozygote advantage.
Under simultaneous action of negative frequency-dependent selection and heterozygote advantage, the alleles increased in frequency just after emergence through a mutation and might stay in relatively high frequencies, up to ca. 0.65, through a few dozens of generations (e.g. "black" allele, generations 1-100).
While the divergence of allopatric species is sustained by geographic barriers, sympatric populations can split through the action of negative frequency-dependent selection, in which rare types gain a fitness advantage over types of high frequency, for example by tapping into an unused and abundant resource.
The action of negative frequency-dependent selection is contingent on the presence of trade-offs to give specialists a fitness advantage over generalists.
It remains unclear whether the mechanisms of action of high-frequency TMS and l-dopa are similar or they could be even synergic.
This makes it difficult for selection to distinguish between different phenotypes, and thus impairs the action of negative frequency-dependent selection to sustain specialization.
Therefore, the mechanism of action of high-frequency TMS depends on changes in neural activity generated in the stimulated, afferent and efferent nuclei of the BG and motor cortex [ 98].
