Individuals with shared genetic ancestry tend to be more genetically similar. Genetic ancestry-The genealogical paths through which an individual inherits DNA from specific ancestors in a reference population. Genetic cline-A gradual change of allele frequencies over a specified geographic area. Population bottleneck-An event that drastically reduces the effective size of a population, leading to increased genetic drift.
Haplotype-A set of linked genetic variants that are coinherited.
#PINPOINT MAPPING SERIAL#
Serial founder effect-The successive loss of genetic variation when populations are sequentially founded by a small number of individuals. Out-of-Africa (OOA) model -Hypothesis that anatomically modern humans evolved in Africa and subsequently peopled the rest of the world.
Population structure-Systematic differences in allele frequencies between subpopulations.Īdmixture-The interbreeding of individuals from two or more subpopulations that were isolated for a relatively short evolutionary time. N e determines the strength of genetic drift acting on a population. Linkage disequilibrium (LD)-The nonrandom association of two alleles at different loci.Įffective population size ( N e)-The number of breeding individuals in an idealized randomly mating population. Finally, we explore the biomedical implications of population structure in Africa on health and disease and call for more ethically conducted studies of genetic variation in Africa. Third, we highlight how natural selection has shaped patterns of genetic variation across the continent, noting that gene flow provides a potent source of adaptive variation and that selective pressures vary across Africa. Furthermore, the genomic signatures of more recent admixture can be found in the Cape Peninsula and throughout the African diaspora. This includes gene flow between different click-speaking Khoe-San populations, the stepwise spread of pastoralism from eastern to southern Africa, multiple migrations of Bantu speakers across the continent, as well as admixture from the Middle East and Europe into the Sahel region and North Africa. Second, we describe the genetic legacies of admixture events that have occurred during the past 10,000 years. First, we give a brief overview of genetic variation in Africa and examine deep population structure within Africa, including the evidence of ancient introgression from archaic “ghost” populations. Each of these historical vignettes paints a recurring picture of population divergence followed by secondary contact. In this review, we view population genetics through the lens of admixture, highlighting how multiple demographic events have shaped African genomes. Importantly, African genomes are heterogeneous: They contain mixtures of multiple ancestries, each of which have experienced different evolutionary histories. I have always been and continue to be pleased with the PinPointR Įspecially now as I know the limits to which it can go.As the ancestral homeland of our species, Africa contains elevated levels of genetic diversity and substantial population structure. However, I would not encourage anyone to do the same. That are heavier and bulkier, and I don’t feel they would have held up as well under the same impact. One reason I chose the PinPointR was its compact size and weight, and I attribute the lack of damage to these characteristics. The same results as before, so despite its tumble, all was good. Retracing previous searches at home yielded Switching on and testing operation, all seemed good. There was slight cosmetic damage to the case and handle assembly, but nothing a quick clean couldn’t fix. Much to my surprise, the wheels were intact, there was no damage to the spokes or rims, and the alignment was It was time to give the PinPointR a going over to try and work out what the likely repair cost would be. Fearing the worst and trying to collect my tools from across the intersection, I picked everything up and back in the Ute to check when I got home. I then caught a glimpse of the radar rolling down the road, whichĬame to rest in the street side culvert. Looking back through the rearview mirror, I could see the street light reflecting off the open door of the canopy. While driving and rounding a sharp bend, I heardĪ loud bang like I’d hit something. Heading home one evening after a long day on-site, I had inadvertently forgotten to lock the doors on the canopy of the Ute where I store my equipment, including the GPR.
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