Concept: Continental Europe
Fine-scale genetic variation between human populations is interesting as a signature of historical demographic events and because of its potential for confounding disease studies. We use haplotype-based statistical methods to analyse genome-wide single nucleotide polymorphism (SNP) data from a carefully chosen geographically diverse sample of 2,039 individuals from the United Kingdom. This reveals a rich and detailed pattern of genetic differentiation with remarkable concordance between genetic clusters and geography. The regional genetic differentiation and differing patterns of shared ancestry with 6,209 individuals from across Europe carry clear signals of historical demographic events. We estimate the genetic contribution to southeastern England from Anglo-Saxon migrations to be under half, and identify the regions not carrying genetic material from these migrations. We suggest significant pre-Roman but post-Mesolithic movement into southeastern England from continental Europe, and show that in non-Saxon parts of the United Kingdom, there exist genetically differentiated subgroups rather than a general ‘Celtic’ population.
In this paper, we use a robust inversion algorithm, which we have tested in many regional studies, to obtain the first global model of Curie-point depth (GCDM) from magnetic anomaly inversion based on fractal magnetization. Statistically, the oceanic Curie depth mean is smaller than the continental one, but continental Curie depths are almost bimodal, showing shallow Curie points in some old cratons. Oceanic Curie depths show modifications by hydrothermal circulations in young oceanic lithosphere and thermal perturbations in old oceanic lithosphere. Oceanic Curie depths also show strong dependence on the spreading rate along active spreading centers. Curie depths and heat flow are correlated, following optimal theoretical curves of average thermal conductivities K = ~2.0 W(m°C)(-1) for the ocean and K = ~2.5 W(m°C)(-1) for the continent. The calculated heat flow from Curie depths and large-interval gridding of measured heat flow all indicate that the global heat flow average is about 70.0 mW/m(2), leading to a global heat loss ranging from ~34.6 to 36.6 TW.
- Proceedings of the National Academy of Sciences of the United States of America
- Published almost 6 years ago
There is a long-standing controversy between two models of the Neolithic transition. The demic model assumes that the Neolithic range expansion was mainly due to the spread of populations, and the cultural model considers that it was essentially due to the spread of ideas. Here we integrate the demic and cultural models in a unified framework. We show that cultural diffusion explains ∼40% of the spread rate of the Neolithic transition in Europe, as implied by archaeological data. Thus, cultural diffusion cannot be neglected, but demic diffusion was the most important mechanism in this major historical process at the continental scale. This quantitative approach can be useful also in regional analysis, the description of Neolithic transitions in other continents, and models of many human spread phenomena.
- Proceedings of the National Academy of Sciences of the United States of America
- Published about 3 years ago
Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins.
Whilst vastly understudied, pathogens of non-native species (NNS) are increasingly recognised as important threats to native wildlife. This study builds upon recent recommendations for improved screening for pathogens in NNS by focusing on populations of Gammarus roeselii in Chojna, north-western Poland. At this location, and in other parts of continental Europe, G. roeselii is considered a well-established and relatively ‘low-impact’ invader, with little understanding about its underlying pathogen profile and even less on potential spill-over of these pathogens to native species.
Cultural transmission can increase the flexibility of behavior, such as bird song. Nevertheless, this flexibility often appears to be constrained, sometimes by preferences for learning certain traits over others, a phenomenon known as “biased” learning or transmission . The sequential colonization of the Atlantic Islands by the chaffinch (Fringilla coelebs)  provides a unique model system in which to investigate how the variability of a cultural trait has evolved. We used novel computational methods to analyze chaffinch song from twelve island and continental populations and to infer patterns of evolution in song structure. We found that variability of the subunits within songs (“syllables”) differed moderately between populations but was not predicted by whether the population was continental or not. In contrast, we found that the sequencing of syllables within songs (“syntax”) was less structured in island than continental populations and in fact decreased significantly after each colonization. Syntactical structure was very clear in the mainland European populations but was almost entirely absent in the most recently colonized island, Gran Canaria. Our results suggest that colonization leads to the progressive loss of a species-specific feature of song, syntactical structure.
The vulnerability of deafblind people is considered axiomatic; they are seen not only as a vulnerable group but also as one of the most vulnerable. This paper aims to synthesise existing knowledge to determine what is known about such vulnerability. A comprehensive literature search was undertaken between April 2013 and May 2014. The review method was informed by systematic review principles. An approach based on a ‘hierarchy of evidence’ would have reduced the amount of literature reviewed significantly, to the point where synthesis would not be possible. Included material was appraised and an interpretative rather than aggregative approach to synthesis adopted. Drawing on principles of critical interpretive synthesis, rather than being a determiner of whether material should be included or excluded, a critique of the literature is offered within the synthesis. Twenty-eight references were identified for inclusion, originating from the UK, USA, Australia, Continental Europe and the Nordic Countries. No empirical studies specifically examining the experience of vulnerability of deafblind people were found. However, deafblind people describe feelings of vulnerability in studies exploring their experiences more generally, and in personal accounts of living with the impairment. Literature produced by practitioners and specialist organisations also explores the topic. Deafblind people are identified as a population ‘at risk’ of various adverse outcomes, particularly when compared to the non-deafblind majority, and deafblind people describe being and feeling vulnerable in various situations. The literature largely relates to negative outcomes and includes significantly less exploration of positive risk taking, coping capacity and resilience. Deafblind people do not appear to describe themselves as being vulnerable as a permanent state, suggesting a need for greater exploration of the experience among all sections of this heterogeneous population, with consideration of the concepts of resilience and coping capacity.
Despite the significance of marine habitat-forming organisms, little is known about their large-scale distribution and abundance in deeper waters, where they are difficult to access. Such information is necessary to develop sound conservation and management strategies. Kelps are main habitat-formers in temperate reefs worldwide; however, these habitats are highly sensitive to environmental change. The kelp Ecklonia radiate is the major habitat-forming organism on subtidal reefs in temperate Australia. Here, we provide large-scale ecological data encompassing the latitudinal distribution along the continent of these kelp forests, which is a necessary first step towards quantitative inferences about the effects of climatic change and other stressors on these valuable habitats. We used the Autonomous Underwater Vehicle (AUV) facility of Australia’s Integrated Marine Observing System (IMOS) to survey 157,000 m2 of seabed, of which ca 13,000 m2 were used to quantify kelp covers at multiple spatial scales (10-100 m to 100-1,000 km) and depths (15-60 m) across several regions ca 2-6° latitude apart along the East and West coast of Australia. We investigated the large-scale geographic variation in distribution and abundance of deep-water kelp (>15 m depth) and their relationships with physical variables. Kelp cover generally increased with latitude despite great variability at smaller spatial scales. Maximum depth of kelp occurrence was 40-50 m. Kelp latitudinal distribution along the continent was most strongly related to water temperature and substratum availability. This extensive survey data, coupled with ongoing AUV missions, will allow for the detection of long-term shifts in the distribution and abundance of habitat-forming kelp and the organisms they support on a continental scale, and provide information necessary for successful implementation and management of conservation reserves.
Canine babesiosis is a parasitic disease caused by apicomplexan protozoa of the genus Babesia, with Babesia canis being a pathogenic and widespread species in mainland Europe. The United Kingdom has thought to have been free of endemic B. canis infection, despite its vector, Dermacentor reticulatus being present in endemic foci. The winter of 2015/2016 saw the establishment of the first recording of a known endemic foci of B. canis in the UK. Since this outbreak in Harlow and subsequent cases in Romford later in 2016, information has been gathered regarding the population of Dermacentor ticks in Harlow and awareness of the disease promoted among Veterinary professionals and pet owners. This letter describes what is known about the two clusters of cases seen in 2016 and the distribution of D. reticulatus in the UK. A further untraveled case in the UK in 2017 close proximity to the 2016 cases is also described, as well as the lessons this outbreak brings in terms of managing other vector-borne disease.
Contrary to other parts of the continent, little information is available regarding semen quality among subjects from central and eastern Europe.