The early Aurignacian dispersal of modern humans into westernmost Eurasia.

Documenting the first appearance of modern humans in a given region is key to understanding the dispersal process and the replacement or assimilation of indigenous human populations such as the Neanderthals. The Iberian Peninsula was the last refuge of Neanderthal populations as modern humans advanced across Eurasia. Here we present evidence of an early Aurignacian occupation at Lapa do Picareiro in central Portugal. Diagnostic artifacts were found in a sealed stratigraphic layer dated 41.1 to 38.1 ka cal BP, documenting a modern human presence on the western margin of Iberia ∼5,000 years earlier than previously known. The data indicate a rapid modern human dispersal across southern Europe, reaching the westernmost edge where Neanderthals were thought to persist. The results support the notion of a mosaic process of modern human dispersal and replacement of indigenous Neanderthal populations.

Lead isotopes in silver reveal earliest Phoenician quest for metals in the west Mediterranean.

When and why did the Phoenicians initiate long-term connections between the Levant and western Europe? This is one of the most hotly debated questions in ancient Mediterranean history and cultural research. In this study, we use silver to answer this question, presenting the largest dataset of chemical and isotopic analyses of silver items from silver hoards found in Phoenician homeland sites. Intertwining lead isotope analysis of silver items with precise archaeological context and chronology, we provide analytical evidence for the onset of Phoenician westward expansion. We suggest that the quest for silver instigated a long, exploratory phase, first in Anatolia (Asia Minor) and Sardinia, and subsequently in the Iberian Peninsula. This phase preceded the establishment of sustainable, flourishing Phoenician colonies in the West by over a century. In so doing, our results buttress the "precolonization" theory, accord it a firm chronological framework, and demonstrate that the quest for silver (and probably other metals) was an incentive for Phoenician westward expansion. Furthermore, our results show that the Phoenicians introduced innovative silver production methods to historic Europe.

Human Genomic Diversity Where the Mediterranean Joins the Atlantic.

Throughout the past few years, a lively debate emerged about the timing and magnitude of the human migrations between the Iberian Peninsula and the Maghreb. Several pieces of evidence, including archaeological, anthropological, historical, and genetic data, have pointed to a complex and intermingled evolutionary history in the western Mediterranean area. To study to what extent connections across the Strait of Gibraltar and surrounding areas have shaped the present-day genomic diversity of its populations, we have performed a screening of 2.5 million single-nucleotide polymorphisms in 142 samples from southern Spain, southern Portugal, and Morocco. We built comprehensive data sets of the studied area and we implemented multistep bioinformatic approaches to assess population structure, demographic histories, and admixture dynamics. Both local and global ancestry inference showed an internal substructure in the Iberian Peninsula, mainly linked to a differential African ancestry. Western Iberia, from southern Portugal to Galicia, constituted an independent cluster within Iberia characterized by an enriched African genomic input. Migration time modeling showed recent historic dates for the admixture events occurring both in Iberia and in the North of Africa. However, an integrative vision of both paleogenomic and modern DNA data allowed us to detect chronological transitions and population turnovers that could be the result of transcontinental migrations dating back from Neolithic times. The present contribution aimed to fill the gaps in the modern human genomic record of a key geographic area, where the Mediterranean and the Atlantic come together.

Alarming decline of freshwater trigger species in western Mediterranean key biodiversity areas.

Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species that trigger either the vulnerability and or the irreplaceability criterion and thus identify a site as a KBA). However, to our knowledge, many of these KBAs have not been validated. Therefore, classical surveys of the taxa used to identify freshwater KBAs (fishes, molluscs, odonates, and aquatic plants) were conducted in Douro (Iberian Peninsula) and Sebou (Morocco) River basins in the Mediterranean Biodiversity Hotspot. Environmental DNA analyses were undertaken in the Moroccan KBAs. There was a mismatch between the supposed and actual presence of trigger species. None of the trigger species were found in 43% and 50% of all KBAs surveyed in the Douro and Sebou basins, respectively. Shortcomings of freshwater KBA identification relate to flawed or lack of distribution data for trigger species. This situation results from a misleading initial identification of KBAs based on poor (or even inaccurate) ecological information or due to increased human disturbance between initial KBA identification and the present. To improve identification of future freshwater KBAs, we suggest selecting trigger species with a more conservative approach; use of local expert knowledge and digital data (to assess habitat quality, species distribution, and potential threats); consideration of the subcatchment when delineating KBAs boundaries; thoughtful consideration of terrestrial special areas for conservation limits; and periodic field validation.

Alarming decline of freshwater trigger species in western Mediterranean Key Biodiversity Areas Resumen La identificación de las áreas clave de biodiversidad (ACB) fue iniciada por la Unión Internacional para la Conservación de la Naturaleza en 2004 con el objetivo de sobreponerse a los sesgos taxonómicos en la selección de áreas importantes para la conservación, incluyendo los ecosistemas de agua dulce. Desde entonces, varias ACB han sido identificadas principalmente con base en la presencia de especies desencadenantes (es decir, especies que desencadenan el criterio de vulnerabilidad o de carácter irremplazable y por lo tanto identifican a un sitio como una ACB). Sin embargo, a nuestro conocimiento, muchas de estas ACB no han sido validadas. Por lo tanto, los censos clásicos de taxones utilizados para identificar las ACB de agua dulce (peces, moluscos, odonatos y plantas acuáticas) fueron realizados en las cuencas de los ríos Duero (Península Ibérica) y Sebou (Marruecos) en el Punto Caliente de Biodiversidad del Mediterráneo. Realizamos análisis de ADN ambiental en las ACB de Marruecos. Hubo una discrepancia entre la supuesta presencia y la actual presencia de especies desencadenantes. Ninguna de las especies desencadenantes se encontró en 43% y 50% de las ACB censadas en las cuencas del Duero y del Sebou, respectivamente. Las deficiencias en la identificación de las ACB de agua dulce están relacionadas con la carencia de datos o datos erróneos sobre la distribución de las especies desencadenantes. Esta situación resulta en una identificación inicial engañosa de las ACB con base en información ecológica deficiente (o incluso incorrecta) o también puede deberse al incremento en las perturbaciones humanas ocurridas entre la identificación de la ACB y el presente. Para mejorar la identificación de ACB de agua dulce en el futuro, sugerimos que la selección de especies desencadenantes se realice con un enfoque más conservador; que se usen el conocimiento local de los expertos y los datos digitales (para evaluar la calidad del hábitat, la distribución de las especies y las amenazas potenciales); que se consideren las subcuencas cuando se delimiten las fronteras de las ACB; que se consideren cuidadosamente las áreas de especies terrestres para los límites de conservación; y que se realicen validaciones periódicas de campo.

Four millennia of Iberian biomolecular prehistory illustrate the impact of prehistoric migrations at the far end of Eurasia.

Population genomic studies of ancient human remains have shown how modern-day European population structure has been shaped by a number of prehistoric migrations. The Neolithization of Europe has been associated with large-scale migrations from Anatolia, which was followed by migrations of herders from the Pontic steppe at the onset of the Bronze Age. Southwestern Europe was one of the last parts of the continent reached by these migrations, and modern-day populations from this region show intriguing similarities to the initial Neolithic migrants. Partly due to climatic conditions that are unfavorable for DNA preservation, regional studies on the Mediterranean remain challenging. Here, we present genome-wide sequence data from 13 individuals combined with stable isotope analysis from the north and south of Iberia covering a four-millennial temporal transect (7,500-3,500 BP). Early Iberian farmers and Early Central European farmers exhibit significant genetic differences, suggesting two independent fronts of the Neolithic expansion. The first Neolithic migrants that arrived in Iberia had low levels of genetic diversity, potentially reflecting a small number of individuals; this diversity gradually increased over time from mixing with local hunter-gatherers and potential population expansion. The impact of post-Neolithic migrations on Iberia was much smaller than for the rest of the continent, showing little external influence from the Neolithic to the Bronze Age. Paleodietary reconstruction shows that these populations have a remarkable degree of dietary homogeneity across space and time, suggesting a strong reliance on terrestrial food resources despite changing culture and genetic make-up.

Finding Amica in the Archives: Navigating a Path between Strategic Collaboration and Independent Research.

This article is a call for US-based historians to consider participating in strategic collaboration with fellow academics in their field. Out of a series of lucky encounters in person and with documentary collections, the authors, both archival historians, created a generous and expansive collaboration both in research and writing. Galvanized by the shift in working conditions occasioned by the coronavirus, the authors map out how the field in the United States should change to accommodate and reward such collaboration.

On the censorship of Tycho Brahe's books in Iberia.

It is known that throughout the seventeenth century the world system proposed by Tycho Brahe (1546-1601) assumed a preponderant position in the Iberian cosmological debate, according to many opinions the one showing the best agreement to empirical evidence. Moreover, the Tychonian model (or variants thereof) did not present the difficulties of apparent contradiction with scriptures, as the heliocentric system of Nicolaus Copernicus (1473-1543) did, since it kept the earth fixed at the centre of the world. However, Tycho, as a Lutheran author, was targeted by the Inquisition. Passages of various works of the Danish astronomer were included in the Spanish Indices of 1632, 1640 and 1707, although the formal condemnation of the Roman Inquisition never materialized. In the network of the Society of Jesus a seemingly informal censorship also circulated, apparently based on Tridentine determinations, published in 1651 in the influential work of Giambattista Riccioli (1598-1671) Almagestum novum. In this paper I will discuss the scope, effects and limitations of the censorship of Tycho's scientific books in Portugal and Spain, through the analysis of several annotated copies, preserved manly in Iberian libraries, with a special attention to books with a well-established provenance in past Jesuit colleges.

Consequences of breed formation on patterns of genomic diversity and differentiation: the case of highly diverse peripheral Iberian cattle.

BACKGROUND: Iberian primitive breeds exhibit a remarkable phenotypic diversity over a very limited geographical space. While genomic data are accumulating for most commercial cattle, it is still lacking for these primitive breeds. Whole genome data is key to understand the consequences of historic breed formation and the putative role of earlier admixture events in the observed diversity patterns. RESULTS: We sequenced 48 genomes belonging to eight Iberian native breeds and found that the individual breeds are genetically very distinct with FST values ranging from 4 to 16% and have levels of nucleotide diversity similar or larger than those of their European counterparts, namely Jersey and Holstein. All eight breeds display significant gene flow or admixture from African taurine cattle and include mtDNA and Y-chromosome haplotypes from multiple origins. Furthermore, we detected a very low differentiation of chromosome X relative to autosomes within all analyzed taurine breeds, potentially reflecting male-biased gene flow. CONCLUSIONS: Our results show that an overall complex history of admixture resulted in unexpectedly high levels of genomic diversity for breeds with seemingly limited geographic ranges that are distantly located from the main domestication center for taurine cattle in the Near East. This is likely to result from a combination of trading traditions and breeding practices in Mediterranean countries. We also found that the levels of differentiation of autosomes vs sex chromosomes across all studied taurine and indicine breeds are likely to have been affected by widespread breeding practices associated with male-biased gene flow.

A western route of prehistoric human migration from Africa into the Iberian Peninsula.

Being at the western fringe of Europe, Iberia had a peculiar prehistory and a complex pattern of Neolithization. A few studies, all based on modern populations, reported the presence of DNA of likely African origin in this region, generally concluding it was the result of recent gene flow, probably during the Islamic period. Here, we provide evidence of much older gene flow from Africa to Iberia by sequencing whole genomes from four human remains from northern Portugal and southern Spain dated around 4000 years BP (from the Middle Neolithic to the Bronze Age). We found one of them to carry an unequivocal sub-Saharan mitogenome of most probably West or West-Central African origin, to our knowledge never reported before in prehistoric remains outside Africa. Our analyses of ancient nuclear genomes show small but significant levels of sub-Saharan African affinity in several ancient Iberian samples, which indicates that what we detected was not an occasional individual phenomenon, but an admixture event recognizable at the population level. We interpret this result as evidence of an early migration process from Africa into the Iberian Peninsula through a western route, possibly across the Strait of Gibraltar.

Did the Romans introduce the Egyptian mongoose (Herpestes ichneumon) into the Iberian Peninsula?

New finds of bones of the Egyptian Mongoose (Herpestes ichneumon), one from Portugal and one from Spain, were directly 14C dated to the first century AD. While the Portuguese specimen was found without connection to the Chalcolithic occupation of the Pedra Furada cave where it was recovered, the Spanish find, collected in the city of Mérida, comes from a ritual pit that also contained three human and 40 dog burials. The finds reported here show that the Egyptian mongoose, contrary to the traditional and predominant view, did not first arrive in the Iberian Peninsula during the Muslim occupation of Iberia. Instead, our findings are consistent with the hypothesis that the species was first introduced by the Romans, or at least sometime during the Roman occupation of Hispania. Therefore, radiocarbon dating of new archaeological finds of bones of the Egyptian Mongoose (Herpestes ichneumon) in the Iberian Peninsula push back the confirmed presence of the species in the region by approximately eight centuries, as the previously oldest dated record is from the ninth century. With these new dates, there are now a total of four 14C dated specimens of Egyptian mongooses from the Iberian Peninsula, and all of these dates fall within the last 2000 years. This offers support for the hypothesis that the presence of the species in Iberia is due to historical introductions and is at odds with a scenario of natural sweepstake dispersal across the Straits of Gibraltar in the Late Pleistocene (126,000-11,700 years ago), recently proposed based on genetic data.

Haemosporidian parasites missed the boat during the introduction of common waxbills (Estrilda astrild) in Iberia.

Exotic species can experience fast expansion in new environments, especially if they left their pathogens behind (Enemy Release hypothesis) or brought novel pathogens to the native competitors (Novel Weapon hypothesis). Common waxbills (Estrilda astrild) are native to sub-Saharan Africa and invaded west Iberia since the 1960s. Past haemosporidian parasite surveys at four locations in Portugal showed that waxbills can be infected with parasites, though with very low prevalence. However, it is not known if this pattern generalizes across their distribution range, or if there are geographic differences in parasite prevalence. It is also not discussed if this is a case of Enemy Release, as opposed to waxbills being also little parasitized in their native range. We screened 617 waxbills in 23 sites in Portugal and detected nine parasite lineages, most of them only known to the Palearctic. Only ten individuals were parasitized, and there was no significant geographical pattern on the prevalence. Overall, this population shows very low prevalence of haemosporidians (1.6% prevalence), which contrasts with significantly higher prevalence in native grounds, as compiled from the literature. These data support Enemy Release as the most likely hypothesis, which may have been important for their success as an exotic species.

Hydrological change in Southern Europe responding to increasing North Atlantic overturning during Greenland Stadial 1.

Greenland Stadial 1 (GS-1) was the last of a long series of severe cooling episodes in the Northern Hemisphere during the last glacial period. Numerous North Atlantic and European records reveal the intense environmental impact of that stadial, whose origin is attributed to an intense weakening of the Atlantic Meridional Overturning Circulation in response to freshening of the North Atlantic. Recent high-resolution studies of European lakes revealed a mid-GS-1 transition in the climatic regimes. The geographical extension of such atmospheric changes and their potential coupling with ocean dynamics still remains unclear. Here we use a subdecadally resolved stalagmite record from the Northern Iberian Peninsula to further investigate the timing and forcing of this transition. A solid interpretation of the environmental changes detected in this new, accurately dated, stalagmite record is based on a parallel cave monitoring exercise. This record reveals a gradual transition from dry to wet conditions starting at 12,500 y before 2000 A.D. in parallel to a progressive warming of the subtropical Atlantic Ocean. The observed atmospheric changes are proposed to be led by a progressive resumption of the North Atlantic convection and highlight the complex regional signature of GS-1, very distinctive from previous stadial events.

A rock engraving made by Neanderthals in Gibraltar.

The production of purposely made painted or engraved designs on cave walls--a means of recording and transmitting symbolic codes in a durable manner--is recognized as a major cognitive step in human evolution. Considered exclusive to modern humans, this behavior has been used to argue in favor of significant cognitive differences between our direct ancestors and contemporary archaic hominins, including the Neanderthals. Here we present the first known example of an abstract pattern engraved by Neanderthals, from Gorham's Cave in Gibraltar. It consists of a deeply impressed cross-hatching carved into the bedrock of the cave that has remained covered by an undisturbed archaeological level containing Mousterian artifacts made by Neanderthals and is older than 39 cal kyr BP. Geochemical analysis of the epigenetic coating over the engravings and experimental replication show that the engraving was made before accumulation of the archaeological layers, and that most of the lines composing the design were made by repeatedly and carefully passing a pointed lithic tool into the grooves, excluding the possibility of an unintentional or utilitarian origin (e.g., food or fur processing). This discovery demonstrates the capacity of the Neanderthals for abstract thought and expression through the use of geometric forms.

Study on environmental indices and heat tolerance tests in hair sheep.

The ability to predict the effects of climatic factors on animals and their adaptability is important for livestock production. The aim of the present study was to analyze whether existing indices are suitable for evaluating heat stress in Santa Ines and Morada Nova sheep, which are locally adapted hair sheep breeds from northeastern Brazil, and if the limits used to classify thermal stress are suitable for these breeds. Therefore, climatic, physiological, and physical parameters, as well as thermographic images, were collected in 26 sheep, 1 1/2 years old, from two genetic groups (Santa Ines 12 males and 4 females; Morada Nov. 7 males and 3 females) for 3 days in both morning (4:00 a.m.) and afternoon (2:00 p.m.) with six repetitions, totalizing 156 repetitions. Statistical analysis included correlations and broken-line regressions. Iberia and Benezra indices were the tolerance tests that best correlated with the assessed parameters. High correlations between environmental indices and rectal or skin surface temperatures was observed, which indicates that these indices can be used for Santa Ines and Morada Nova sheep raised in central Brazil. However, some indicative values of thermal discomfort are different from the existing classification. Therefore, in order to classify appropriately, the model used needs to be carefully studied, because these classifying values can vary according to the species and model. Further research is necessary to establish indicators of thermal stress for sheep breeds raised in the region.

Cenozoic tectonic and climatic events in southern Iberian Peninsula: Implications for the evolutionary history of freshwater fish of the genus Squalius (Actinopterygii, Cyprinidae).

Southern Iberian freshwater ecosystems located at the border between the European and African plates represent a tectonically complex region spanning several geological ages, from the uplifting of the Betic Mountains in the Serravalian-Tortonian periods to the present. This area has also been subjected to the influence of changing climate conditions since the Middle-Upper Pliocene when seasonal weather patterns were established. Consequently, the ichthyofauna of southern Iberia is an interesting model system for analyzing the influence of Cenozoic tectonic and climatic events on its evolutionary history. The cyprinids Squalius malacitanus and Squalius pyrenaicus are allopatrically distributed in southern Iberia and their evolutionary history may have been defined by Cenozoic tectonic and climatic events. We analyzed MT-CYB (510 specimens) and RAG1 (140 specimens) genes of both species to reconstruct phylogenetic relationships and to estimate divergence times and ancestral distribution ranges of the species and their populations. We also assessed their levels of genetic structure and diversity as well as the amount of gene flow between populations. To investigate recent paleogeographical and climatic factors in southern Iberia, we modeled changes-through-time in sea level from the LGM to the present. Phylogenetic, geographic and population structure analyses revealed two well-supported species (S. malacitanus and S. pyrenaicus) in southern Iberia and two subclades (Atlantic and Mediterranean) within S. malacitanus. The origin of S. malacitanus and the separation of its Atlantic and Mediterranean populations occurred during the Serravalian-Tortonian and Miocene-Pliocene periods, respectively. These divergence events occurred in the Middle Pliocene and Pleistocene in S. pyrenaicus. In both species, Atlantic basins possessed populations with higher genetic diversity than Mediterranean, which may be explained by the Janda Lagoon. The isolation of S. malacitanus was earlier and related to the rising of the Betic Mountains. Divergence of its Atlantic and Mediterranean populations was associated with the creation of the freshwater systems of southern Iberia close to the Gibraltar Strait. The presence of S. pyrenaicus in southern Iberia may be the result of recent colonization associated with river capture, as demonstrated our biogeographic reconstruction.

Direct U-series analysis of the Lezetxiki humerus reveals a Middle Pleistocene age for human remains in the Basque Country (northern Iberia).

In 1964, a human humerus was found in a sedimentary deposit in Lezetxiki Cave (Basque Country, northern Iberia). The first studies on the stratigraphy, associated mammal faunal remains and lithic implements placed the deposits containing the humerus into the Riss glacial stage. Direct chronometric evidence has so far been missing, and the previous chronostratigraphic framework and faunal dating gave inconsistent results. Here we report laser ablation U-series analyses on the humerus yielding a minimum age of 164 ± 9 ka, corresponding to MIS 6. This is the only direct dating analysis of the Lezetxiki humerus and confirms a Middle Pleistocene age for this hominin fossil. Morphometric analyses suggest that the Lezetxiki humerus has close affinities to other Middle Pleistocene archaic hominins, such as those from La Sima de los Huesos at Atapuerca. This emphasizes the significance of the Lezetxiki fossil within the populations that predate the Neanderthals in south-western Europe. It is thus an important key fossil for the understanding of human evolution in Europe during the Middle Pleistocene, a time period when a great morphological diversity is observed but whose phylogenetic meaning is not yet fully understood.

Demographic differences between funerary caves and megalithic graves of northern Spanish Late Neolithic/Early Chalcolithic.

OBJECTIVES: The study focuses on the estimation of demographic parameters of Late Neolithic/Early Chalcolithic (mid 4th-early 3rd millenniums cal. BC) burial sites from the La Rioja region (Ebro valley, northern Spain) to identify demographic characteristics. MATERIALS AND METHODS: The human remains come from three caves (Las Yurdinas II, Peña Larga, and La Peña de Marañón) and three megalithic graves (Alto de la Huesera, San Martín, and Peña Guerra II). The total skeletal sample consists of a minimum of 261 individuals, 149 being buried in caves and 112 in megalithic graves. Data based on age and sex estimation are analyzed using abridged life tables, mortality rates, and sex ratios. RESULTS: A systematic bias against children under 5 years of age is detected both in caves (5 q0 = 187.92%) and megalithic graves (5 q0 = 71.43%) but also against some juveniles and adults compared with population models, though a statistically significant greater lack of infants is worth noting in the megaliths (t-test, P = 0.012). Moreover, a significant divergence in sex ratios (χ(2) , P = 0.002) is also identified between site types, clearly prioritizing women in caves (sex ratio = 0.45) and men in megalithic graves (sex ratio = 1.33). CONCLUSIONS: This evidence is interpreted as the result of different selective burial patterns. The mortuary variability could lie behind intragroup differential status relationships, though the hypothesis of two populations performing distinct funerary practices in a small region cannot be rejected at the present state of the research. Am J Phys Anthropol 160:284-297, 2016. © 2016 Wiley Periodicals, Inc.

Gene flow from North Africa contributes to differential human genetic diversity in southern Europe.

Human genetic diversity in southern Europe is higher than in other regions of the continent. This difference has been attributed to postglacial expansions, the demic diffusion of agriculture from the Near East, and gene flow from Africa. Using SNP data from 2,099 individuals in 43 populations, we show that estimates of recent shared ancestry between Europe and Africa are substantially increased when gene flow from North Africans, rather than Sub-Saharan Africans, is considered. The gradient of North African ancestry accounts for previous observations of low levels of sharing with Sub-Saharan Africa and is independent of recent gene flow from the Near East. The source of genetic diversity in southern Europe has important biomedical implications; we find that most disease risk alleles from genome-wide association studies follow expected patterns of divergence between Europe and North Africa, with the principal exception of multiple sclerosis.

Direct estimates of natural selection in Iberia indicate calcium absorption was not the only driver of lactase persistence in Europe.

Lactase persistence (LP) is a genetically determined trait whereby the enzyme lactase is expressed throughout adult life. Lactase is necessary for the digestion of lactose--the main carbohydrate in milk--and its production is downregulated after the weaning period in most humans and all other mammals studied. Several sources of evidence indicate that LP has evolved independently, in different parts of the world over the last 10,000 years, and has been subject to strong natural selection in dairying populations. In Europeans, LP is strongly associated with, and probably caused by, a single C to T mutation 13,910 bp upstream of the lactase (LCT) gene (-13,910*T). Despite a considerable body of research, the reasons why LP should provide such a strong selective advantage remain poorly understood. In this study, we examine one of the most widely cited hypotheses for selection on LP--that fresh milk consumption supplemented the poor vitamin D and calcium status of northern Europe's early farmers (the calcium assimilation hypothesis). We do this by testing for natural selection on -13,910*T using ancient DNA data from the skeletal remains of eight late Neolithic Iberian individuals, whom we would not expect to have poor vitamin D and calcium status because of relatively high incident UVB light levels. None of the eight samples successfully typed in the study had the derived T-allele. In addition, we reanalyze published data from French Neolithic remains to both test for population continuity and further examine the evolution of LP in the region. Using simulations that accommodate genetic drift, natural selection, uncertainty in calibrated radiocarbon dates, and sampling error, we find that natural selection is still required to explain the observed increase in allele frequency. We conclude that the calcium assimilation hypothesis is insufficient to explain the spread of LP in Europe.

Revisiting the Iberian honey bee (Apis mellifera iberiensis) contact zone: maternal and genome-wide nuclear variations provide support for secondary contact from historical refugia.

Dissecting diversity patterns of organisms endemic to Iberia has been truly challenging for a variety of taxa, and the Iberian honey bee is no exception. Surveys of genetic variation in the Iberian honey bee are among the most extensive for any honey bee subspecies. From these, differential and complex patterns of diversity have emerged, which have yet to be fully resolved. Here, we used a genome-wide data set of 309 neutrally tested single nucleotide polymorphisms (SNPs), scattered across the 16 honey bee chromosomes, which were genotyped in 711 haploid males. These SNPs were analysed along with an intergenic locus of the mtDNA, to reveal historical patterns of population structure across the entire range of the Iberian honey bee. Overall, patterns of population structure inferred from nuclear loci by multiple clustering approaches and geographic cline analysis were consistent with two major clusters forming a well-defined cline that bisects Iberia along a northeastern-southwestern axis, a pattern that remarkably parallels that of the mtDNA. While a mechanism of primary intergradation or isolation by distance could explain the observed clinal variation, our results are more consistent with an alternative model of secondary contact between divergent populations previously isolated in glacial refugia, as proposed for a growing list of other Iberian taxa. Despite current intense honey bee management, human-mediated processes have seemingly played a minor role in shaping Iberian honey bee genetic structure. This study highlights the complexity of the Iberian honey bee patterns and reinforces the importance of Iberia as a reservoir of Apis mellifera diversity.