This field attempts to account for evolution in terms of changes in gene and genotype frequencies within populations and the processes that convert the variation with populations into more or less permanent variation between species.
Further evidence of evolution as a basic model was biology's goals of understanding "what creates, maintains, and leads to the loss of genetic variation with populations" (Charles) and "trying to predict changes in allele frequency over time" (Gregor).
We are progressing from genome-wide association studies (GWASs), involving 10 single nucleotide polymorphisms (SNPs) and providing insight into common gene variations with population frequency >5%, to whole-exon sequencing of 1.5% of the genome, finding rare and low frequency elements, to whole genome sequencing, allowing an understanding of regulatory as well as coding sequences.
Li et al. (2000) detected 13 QTLs for FLL, FLW, FLA and length-width ratio (LWR), explained 8.7% ~ 18.5% of phenotypic variation, with DH population from a cross of Zhaiye Qing 8 and Jingxi 17.
A future study over multiple years would be required to determine if genetic variation was associated with population density variation.
The potential for evolution in response to new stresses, including invasives and climate change, depends on within-population genetic variation, which could be reduced by the widespread use of releases with limited variation compared with populations mixtures from within seed zones.
We contrasted this variation with selected populations worldwide, with the view of placing southeastern Bantu-speakers in the context of global genetic diversity.
Selection for adaptation to different altitudes appears to be the main factor that has determined the observed clinal variation, along with population-size effects.
Because all of these populations occupy regions that were glaciated during the Pleistocene and show reduced levels of neutral genetic variation compared with populations from the centre of the range (Griffin and Willi 2014), we suggest that a history of population bottlenecks is a plausible explanation for at least part of the observed heterosis.
When samples were grouped according to host, results were similar with variation within populations (57.96%) greater than that observed for populations within groups (36.42%).
