This pattern can be observed during evolution of many complications, including metabolic acidosis, pneumonia, acute flaccid paralysis (involving the inter-costal muscles) or brain damage, where there may be an intial compensatory rise in respiratory rate followed by a fall when the body decompensates.
The greater frequency of small-sized beneficial mutations [12], the L-shaped distribution of mutations fixed throughout evolution [13], the existence of fitness equilibriums [14], and the absence of intrinsically beneficial or intrinsically deleterious mutations have all been observed during laboratory evolution, and all conform to the conditions set forth under FGM.
Many such examples have been observed during laboratory evolution, whereby organisms have evolved to narrow or shift their range of preferred temperatures [ 4], carbon sources [ 5, 6], host organisms [ 7], or even laboratory water supply [ 8].
Mutations that cyclically appear have been observed during the evolution of other phage, although usually as a result of iterative passages between different environmental conditions (for example, see [ 25]).
Variant lineages have previously been observed during the natural or directed evolution of other phenotypes, including the evolution of drug-resistant HIV-1 [ 20], the evolution of φX174 bacteriophage with altered host ranges and thermal optima [ 21], and the evolution of ribozymes that could cleave a novel substrate [ 22].
For example, on Si (111) neither this type of transition nor the Au clusters or the wiggly Au nanostructures were observed during the evolution of the self-assembled Au droplets while varying the Ta between 50°C and 850°C [34], but very high density dome-shaped Au droplets were observed throughout the temperature range.
In control berries, a constant decrease of titratable acidity, well correlated with both malic and tartaric acid degradation, was observed during ripening evolution.
A recent study showed that an increased activity of xylose isomerase was observed during adaptive evolution, which in part contributed to efficient xylose assimilation [ 8].
Interestingly, loss of major TE families was observed during the evolution of the sarcopterygian lineage, with a particularly strong reduction in TE diversity in birds and mammals.
A significant improvement in ethanol yield from 0.32 to 0.41 g g-1 on consumed sugars was observed during the evolution and as a consequence, there was a gradual decrease in biomass yield on consumed sugars.
