The findings showed that small-scale evolution in beak size and shape can occur in less than a year, far faster than previously had been believed for long-lived animals like birds.
This definition encompasses small-scale evolution (changes in gene — or more precisely and technically, allele — frequency in a population from one generation to the next) and large-scale evolution (the descent of different species from a common ancestor over many generations).
The sextet is, therefore, the smallest unit of evolution in overlapping genes.
As the precision of both estimators requires the true effective population size to be relatively small, their use is currently limited to scenarios in conservation biology and perhaps studies of the ecology and evolution in small populations.
Concerted evolution via interlocus gene conversion is increasingly recognized as a major feature of evolution in small multigene families (e.g., [ 37, 47- 49]).
However, the difference between the true founder and our approximation will be small compared to the evolution in the many years of follow-up after the first sample.
Positive coefficients for population sizes of 1 and 10 indicated that evolution in small populations is strongly associated with increased ΔmtDNA prevalence (P = 0.004 and 0.001, respectively, table 3).
It is possible that long-term evolution in small N e, exacerbated by the androdioecious reproductive mode of this species, might render natural selection at the population level too weak to effectively combat ΔmtDNA accumulation in C. briggsae.
The Passiflora clade has a similar age as E. ensifera, namely ca. 11 my, and its diversification apparently resulted from rapid evolution in small isolated populations in the high Andes [ 10].
In each of these three cases, there seems to be faster evolution in smaller populations, as would be predicted based on the nearly neutral model.
