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SARS-CoV-2 epidemics quickly propagated worldwide, sorting virus genomic variants in newly established propagules of infections. Stochasticity in transmission within and between countries or an actual selective advantage could explain the global high frequency reached by some genomic variants. Using statistical analyses, demographic reconstructions, and molecular dynamics simulations , we show that the globally invasive G614 spike variant i) underwent a significant demographic expansion in most countries not explained by stochastic effects nor by overrepresentation in clinical samples; ii) increases the spike S1/S2 furin-like site conformational plasticity (short-range effect), and iii) modifies the internal motion of the receptor-binding domain affecting its cross-connection with other functional domains (long-range effect). Our results support the hypothesis of a selective advantage at the basis of the spread of the G614 variant, which we suggest may be due to structural modification of the spike protein at the S1/S2 proteolytic site, and provides structural information to guide the design of variant-specific drugs.

Although predictable in its areas of occurrence, many aspects of humpback whale migration are still poorly understood. Nuclear DNA analysis has revealed a low level of relatedness among whales using the same migratory corridor, and has shown that closely related individuals tend not to travel in spatial association. Yet it still remains uncertain whether whales from different matrilineally discrete feeding stocks travel along the same migratory corridor for later mixing in common breeding waters. The western and central South Pacific Ocean is the only ocean basin where thousands of islands and reefs occur as suitable wintering habitat for humpback whales, so here their migratory behaviour may not be constrained by habitat. We analysed sex-specific and temporal distributions of 42 mitochondrial haplotypes detected in 135 humpback whales sampled off eastern Australia throughout 1 annual migration. A noticeable difference was found in haplotypic composition between northbound males and females, suggesting that the 2 sexes of any single matrilineal stock might select different and only partially overlapping migratory routes. We hypothesise that males most closely related to the N-S migrating females off eastern Australia migrate north elsewhere, perhaps past New Zealand. These findings suggest that longitudinal movements by male humpback whales are probably more extensive than currently thought, and indicate the need for reexamination of genetic data from humpback whales in the South Pacific, disaggregated by gender. © Inter-Research 2010 · www.int-res.com.

In this essay we explore questions on how to increase the visibility and utility of genetic information for biodiversity managers and policy makers. This is discussed in the light of Aichi CBD Target 13, which for the first time impels signatories to minimise genetic erosion and safeguard genetic diversity. Drawing on qualitative results from a questionnaire sent to European conservation professionals by the ConGRESS Framework 7 Support Action (http://www.congressgenetics.eu), we summarise our preliminary findings on the attitudes and experiences of European conservation professionals in using genetics. We then discuss the implications of these findings for academics involved in conservation genetics and suggest that a much closer partnership between academic conservation geneticists and conservation practitioners is necessary if the full potential of genetic tools in conservation is to be realised.

Organisms provide some of the most sensitive indicators of climate change and evolutionary responses are becoming apparent in species with short generation times. Large datasets on genetic polymorphism that can provide an historical benchmark against which to test for recent evolutionary responses are very rare, but an exception is found in the brown-lipped banded snail (Cepaea nemoralis). This species is sensitive to its thermal environment and exhibits several polymorphisms of shell colour and banding pattern affecting shell albedo in the majority of populations within its native range in Europe. We tested for evolutionary changes in shell albedo that might have been driven by the warming of the climate in Europe over the last half century by compiling an historical dataset for 6,515 native populations of C. nemoralis and comparing this with new data on nearly 3,000 populations. The new data were sampled mainly in 2009 through the Evolution MegaLab, a citizen science project that engaged thousands of volunteers in 15 countries throughout Europe in the biggest such exercise ever undertaken. A known geographic cline in the frequency of the colour phenotype with the highest albedo (yellow) was shown to have persisted and a difference in colour frequency between woodland and more open habitats was confirmed, but there was no general increase in the frequency of yellow shells. This may have been because snails adapted to a warming climate through behavioural thermoregulation. By contrast, we detected an unexpected decrease in the frequency of Unbanded shells and an increase in the Mid-banded morph. Neither of these evolutionary changes appears to be a direct response to climate change, indicating that the influence of other selective agents, possibly related to changing predation pressure and habitat change with effects on micro-climate.

Comparisons between archaeological findings and allele frequencies at protein loci suggest that most genes of current Europeans descend from populations that have been expanding in Europe in the last 10,000 years, in the Neolithic period. Recent mitochondrial data have been interpreted as indicating a much older, Paleolithic ancestry. In a spatial autocorrelation study at seven hypervariable loci in Europe (four microsatellites, two larger, tandem-repeat loci, and a sequence polymorphism) broad clinal patterns of DNA variation were recognized. The observed clines closely match those described at the protein level, in agreement with a possible Near Eastern origin for the ancestral population. Separation times between populations were estimated on the basis of a stepwise mutation model. Even assuming low mutation rates and long generation times, we found no evidence for population splits older than 10,000 years, with the predictable exception of Saami (Lapps). The simplest interpretation of these results is that the current nuclear gene pool largely reflects the westward and northward expansion of a Neolithic group. This conclusion is now supported by purely genetic evidence on the levels and patterns of microsatellite diversity, rather than by correlations of biological and non-biological data. We argue that many mitochondrial lineages whose origin has been traced back to the Paleolithic period probably reached Europe at a later time.