Artificially selected populations can be subjected to much stronger selection pressures than natural populations, thus their adaption to a new experimental environment can be considered to be a process of accelerated evolution.
Due to population growth, but also adaption of developing countries, especially China, to the western civilization, the meat demand is steadily increasing (OECD-FAO 2017).
We find that cell-cell variability, or intercellular noise, is consistently beneficial in the presence of extreme environmental fluctuations, and that it provides an efficient population-level mechanism for adaption in a deteriorating environment.
Loss or gain of genes within bacterial populations may indicate niche adaption of bacterial subpopulations [ 23].
In each of these worries about evolution, relative to population thinking, human races, and adaption hypotheses, there seems to be little or no appeal to Biblical literalism.
In real systems, one may expect that θdecreases during the adaption of the population.
Yet another recent study of adaptation in large yeast populations did not observe that the speed of adaptation decreased during adaption under conditions where multiple mutations were presumed to be pervasive, and found that variation in fitness was higher at higher Nμb, supporting the multiple mutation model of adaptation [ 9].
As noted below, HGT processes can be triggered by various different stresses including chemical exposure and contribute to the adaption of bacterial populations to changing environmental conditions.
Such studies have been performed in both selected sexual and asexual populations and have provided insights to adaption from beneficial alleles originating in the standing variation in the base population as well as appearing as new mutations during selection.
In Brown's paper, the Copy number variation elements (CNVE) appeared to be consistent with extensive population substructuring (i.e., local adaption) among zebrafish population, with 4,199 (69%) of the identified CNVEs unique to one strain and only 457 (7.5%) CNVEs are common to all four groups [ 50].
