History of Adaptation / Ancient Genomes to Modern Humans

Much, much more! Full article: http://www.nature.com/articles/nrg.2017.65?WT.feed_name=subjects_biological-sciences

Harnessing ancient genomes to study the history of human adaptation

Stephanie Marciniak1& George H. Perry1, 2, 3, / Nature Reviews Genetics 18, 659–674 (201 Published online:

Abstract / The past several years have witnessed an explosion of successful ancient human genome-sequencing projects, with genomic-scale ancient DNA data sets now available for more than 1,100 ancient human and archaic hominin (for example, Neandertal) individuals. Recent ‘evolution in action’ analyses have started using these data sets to identify and track the spatiotemporal trajectories of genetic variants associated with human adaptations to novel and changing environments, agricultural lifestyles, and introduced or co-evolving pathogens. Together with evidence of adaptive introgression of genetic variants from archaic hominins to humans and emerging ancient genome data sets for domesticated animals and plants, these studies provide novel insights into human evolution and the evolutionary consequences of human behaviour that go well beyond those that can be obtained from modern genomic data or the fossil and archaeological records alone.

Main / Reconstructing the history of human biological adaptation has fascinated scientists (and many others) for more than 150 years1,2. How did humans evolve in response to the new environments they encountered while expanding across the globe3? Did prehistoric human populations adapt biologically to cultural changes such as the dietary shifts associated with agriculture4? Do our past adaptations have consequences for health and medicine today, especially given the extent to which some modern human environments and diets differ from those of the past?

With the human reference genome as a cornerstone and benefiting from advances in genotyping and sequencing technology, evolutionary population genetic analyses have greatly aided the study of human biological adaptation. That is, on the basis of patterns of genetic variation observed among living people, researchers can identify genome regions that contain putative ‘signatures’ of past positive natural selection5,6. If the functional consequences of candidate genetic variants can be determined using genotype–phenotype association studies7 or animal or cell model experiments8,9, then the plausibility of past adaptation can be evaluated with the comparative method — that is, by asking whether a phenotype evolves repeatedly and independently under similar environmental pressures10 — or by using other, similarly indirect, approaches.

By contrast, analyses of ‘time-stamped’ ancient DNA data can provide more direct evidence of past human adaptation by facilitating precise ‘evolution in action’ tracking of genetic variants before, during and following selection events11,12. Excitingly, recent major advances in ancient DNA and sequencing methods (Box 1) have facilitated a shift in this field from the analysis of mitochondrial genomes for a small number of individuals to the generation of genome-wide data sets (whole nuclear genome, exome, or genome-wide single-nucleotide polymorphism (SNP) data) at the scale of large populations13,14. In fact, ancient genomes are now available for >1,100 archaic hominins and anatomically modern humans (Fig. 1a) representing time periods from the Middle Pleistocene (430,000 years before present (BP)) to the early 20th century (Fig. 1b; Table 1). Importantly for our understanding of human evolution, analyses of these data sets can provide high-resolution snapshots of the adaptive histories of genetically mediated behaviour, metabolism, soft tissue and other non-skeletal phenotypes not preserved in the fossil or archaeological records.

much more…

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Hollywood adaptations: Shakespeare’s A Midsummer Night’s Dream, LOL.

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