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Hybridisation and gene flow can have both deleterious and adaptive consequences for natural populations and species. To better understand the extent of hybridisation in nature and the balance between its beneficial and deleterious outcomes in a changing environment, information on naturally hybridising nonmodel organisms is needed. This requires the characterisation of the structure and extent of natural hybrid zones. Here, we study natural populations of five keystone mound-building wood ant species in the Formica rufa group across Finland. No genomic studies across the species group exist, and the extent of hybridisation and genomic differentiation in sympatry is unknown. Combining genome-wide and morphological data, we demonstrate more extensive hybridisation than was previously detected between all five species in Finland. Specifically, we reveal a mosaic hybrid zone between Formica aquilonia, F. rufa and F. polyctena, comprising further generation hybrid populations. Despite this, we find that F. rufa, F. aquilonia, F. lugubris and F. pratensis form distinct gene pools in Finland. We also find that hybrids occupy warmer microhabitats than the nonadmixed populations of cold-adapted F. aquilonia, and suggest that warm winters and springs, in particular, may benefit hybrids over F. aquilonia, the most abundant F. rufa group species in Finland. In summary, our results indicate that extensive hybridisation may create adaptive potential that could promote wood ant persistence in a changing climate. Additionally, they highlight the potentially significant ecological and evolutionary consequences of extensive mosaic hybrid zones, within which independent hybrid populations face an array of ecological and intrinsic selection pressures.

Contains fulltext : 282305.pdf (Publisher’s version ) (Open Access), Aim: To describe variation in task shifting from GPs to practice assistants/nurses in 34 countries and to explain differences by analysing associations with characteristics of the GPs and their practices and features of the health care systems. Background: Redistribution of tasks and responsibilities in primary care are driven by changes in demand, such as the growing number of patients with chronic conditions, and workforce developments, including staff shortage. The need to manage an expanding range of services has led to adaptations in the skill-mix of primary care teams. These developments are hampered by barriers between professional domains. Methods: Data were collected between 2011 and 2013 through a cross-sectional survey among approximately 7,200 general practitioners (GPs) in 34 countries. Task shifting is measured through a composite score of GPs' self-reported shifting of tasks. Independent variables at GP and practice level are as follows: innovativeness; part-time working; availability of staff; location and population of the practice. Country-level independent variables are as follows: demand for and supply of care, nurse prescribing, and professionalisation of practice assistants/nurses. Multilevel analysis is used to account for clustering of GPs in countries. Findings: Countries vary in the degree of task shifting. Regarding GP and practice characteristics, use of electronic health records and availability of support staff in the practice are positively associated with task shifting and GPs' working hours negatively, in line with our hypotheses. Age of the GPs is, contrary to our hypothesis, positively related to task shifting. These variables explain 11% of the variance at GP level. Two country variables are related to task shifting: a lower percentage of practices without support staff in a country and nurse prescribing rights coincide with more task shifting. The percentage of practices without support staff has the strongest relationship, expla

The application of demographic history modelling and inference to the study of divergence between species has become a cornerstone of speciation genomics. Speciation histories are usually reconstructed by analysing single populations from each species, assuming that the inferred population history represents the actual speciation history. However, this assumption may not be met when species diverge with gene flow, for example, when secondary contact may be confined to specific geographic regions. Here, we tested whether divergence histories inferred from heterospecific populations may vary depending on their geographic locations, using the two wood ant species Formica polyctena and F. aquilonia. We performed whole-genome resequencing of 20 individuals sampled in multiple locations across the European ranges of both species. Then, we reconstructed the histories of distinct heterospecific population pairs using a coalescent-based approach. Our analyses always supported a scenario of divergence with gene flow, suggesting that divergence started in the Pleistocene (c. 500 kya) and occurred with continuous asymmetrical gene flow from F. aquilonia to F. polyctena until a recent time, when migration became negligible (2–19 kya). However, we found support for contemporary gene flow in a sympatric pair from Finland, where the species hybridise, but no signature of recent bidirectional gene flow elsewhere. Overall, our results suggest that divergence histories reconstructed from a few individuals may be applicable at the species level. Nonetheless, the geographical context of populations chosen to represent their species should be taken into account, as it may affect estimates of migration rates between species when gene flow is spatially heterogeneous.