This could represent a case of a unique adaptive peak or a case of various peaks of equivalent fitness, spread over a rugged landscape, and potentially connected between them.
The essential difference between neutral genetic drift and adaptive evolution is that in the former case mutations that have no substantial effect on fitness spread stochastically in a population, while in the latter case mutations spread because they are beneficial and so favored by selection.
Once a resistant virus with high fitness spreads in the population, the relatively rare de novo development of resistance in other people can be completely neglected because it is out-weighted by the multiplication of the virus in the population.
Since the broadcast, pole dancing for fitness has spread through China.
Then, parents who really do care about their childrens' welfare, i.e., who are 'real' altruists, will have a higher inclusive fitness, hence spread more of their genes, than parents who only pretend to care, or who do not care.
Male killing endosymbionts without explicit fitness compensation spread as a group selected trait into a metapopulation.
The ability of these viruses to sustain their fitness and spread among persons should be considered when shaping future strategies for treating and preventing seasonal and pandemic influenza.
These P. infestans examples illustrate how pathogen populations can experience rapid turnover as new genotypes with greater fitness emerge, spread, out-compete and replace earlier genotypes.
As concern about Strava's fitness tracking spreads like a contagion, thanks to the apparent exposure of U.S. military bases, there are good reasons for the general user to be concerned about the privacy of the popular healthy living app and its competitors.
Polyandry has repeatedly been discussed as a powerful strategy to increase fitness by spreading the risk of low quality matings, as well as to increase the genetic diversity among offspring [ 42, 46].
The spa itself, which is opened to nonguests, does not feel much like an escape, and has an awkward setup: the facilities — the 10 treatment rooms, the nail and hair salon and a small fitness center — are spread out along the public corridor of the hotel's main building.
