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The relative impact of selection, chance and history will determine the predictability of evolution. There is a lack of empirical research on this subject, particularly in sexual organisms. Here we use experimental evolution to test the predictability of evolution. We analyse the real-time evolution of Drosophila subobscura populations derived from contrasting European latitudes placed in a novel laboratory environment. Each natural population was sampled twice within a three-year interval. We study evolutionary responses at both phenotypic (life-history, morphological and physiological traits) and karyotypic levels for around 30 generations of laboratory culture. Our results show (1) repeatable historical effects between years in the initial state, at both phenotypic and karyotypic levels; (2) predictable phenotypic evolution with general convergence except for body size; and (3) unpredictable karyotypic evolution. We conclude that the predictability of evolution is contingent on the trait and level of organization, highlighting the importance of studying multiple biological levels with respect to evolutionary patterns.

Introduction: Sexually transmitted infections (STIs) continue to occur at high levels. According to the WHO, each year there are an estimated 374 million new infections with syphilis, gonorrhea, chlamydia, and trichomoniasis. STIs are associated with an increased risk of acquiring HIV infection. Migrants are reportedly highly affected by STIs. Objectives: This study aims to characterize factors associated with STIs in a population of HIV-positive migrants living in Portugal. Methodology: This is a cross-sectional observational study of 265 newly diagnosed HIV-1 positive migrants, who were defined as individuals born outside Portugal. This group of people were part of the BESTHOPE study that was developed in 17 Portuguese hospitals between September 2014 and December 2019, and included information collected through sociodemographic and behavioral questionnaires filled in by the migrant patients, clinical questionnaires filled in by the clinicians and HIV-1 genomic sequences generated through resistance testing (Sanger sequencing). A multivariable statistical analysis was used to analyze the association between sociodemographic characteristics, sexual behaviors, HIV testing and sexual infections. Results: Most HIV-1 positive individuals included in the study were men (66.8%) and aged between 25 and 44 years old (59.9%). Men had a higher proportion of STIs when compared to women (40.4% vs. 14.0%) and the majority of men reported homosexual contacts (52.0%). Most men reported having had two or more occasional sexual partners in the previous year (88.8%) and 50.9% reported always using condoms with occasional partners, while 13.2% never used it. For regular partners, only 29.5% of the women reported using condoms, compared to 47.3% of men. Other risk behaviors for acquiring HIV, such as tattooing and performing invasive medical procedures, were more prevalent in men (38.0% and 46.2%, respectively), when compared to women (30.4% and 45.1% respectively) and 4.7% of men reported having already shared injectable materials, with no data for comparison in the case for women. Additionally, 23.9% of women reported having had a blood transfusion while only 10.3% of men reported having had this medical procedure. Meanwhile, 30.9% of the individuals reported having been diagnosed with some type of STI in the last 12 months. In addition, 43.3% of individuals that answered a question about hepatitis reported to be infected with hepatitis B, while 13.0% reported having hepatitis C infection. According to the multivariable analysis, the only transmission route was significantly associated with reports of previous STI infection: men who have sex with men (MSM) were 70% more likely to have been diagnosed with an STI in the past 12 months compared to the heterosexual route. Conclusion: HIV-1 infected men were more likely to report previous STIs than women. On the other hand, most migrant women had a regular sexual partner and never or only sometimes used condoms. This somewhat discrepant findings suggest that gender inequalities may make women unable to negotiate safe sexual practices, resulting in increased susceptibility to infection. However, since migrant women report less STIs, we cannot exclude that these STIs may remain undiagnosed. The implementation of safer sex awareness campaigns for condom use and screening for STIs in women is crucial. On the other hand, health education campaigns for STI knowledge need to be implemented for both MSM and women and their partners. [ABSTRACT FROM AUTHOR]

Ongoing climate change is expected to cause an increase in temperature and a reduction of precipitation levels in the Mediterranean region, which might cause changes in many species distributions. These effects negatively influence species gene pools, decreasing genetic variability and adaptive potential. Here, we use mitochondrial DNA and RADseq to analyse population genetic structure and genetic diversity of the bumblebee species Bombus terrestris (subspecies Bombus terrestris lusitanicus), in the Iberian Peninsula. Although this subspecies shows a panmictic pattern of population structure across Iberia and beyond, we found differentiation between subspecies B. t. lusitanicus and B. t. africanus , probably caused by the existence of barriers to gene flow between Iberia and North Africa. Furthermore, the results revealed that the Iberian Peninsula harbours a large fraction of B. terrestris intraspecific genetic variation, with the highest number of mitochondrial haplotypes found when compared with any other region in Europe studied so far, suggesting a potential role for the Iberian Peninsula as a glacial refugium. Our findings strengthen the idea that Iberia is a very important source of diversity for the global genetic pool of this species, because rare alleles might play a role in population resilience against human- or climate-mediated changes. [ABSTRACT FROM AUTHOR]

Human‐mediated introductions of species may have profound impacts on native ecosystems. One potential impact with largely unforeseen consequences is the potential admixture of introduced with autochthonous species through hybridization. Throughout the world, bumblebees have been deliberately introduced for crop pollination with known negative impacts on native pollinators. Given the likely allochthonous origin of commercial bumblebees used in Portugal (subspecies Bombus terrestris terrestris and B. t. dalmatinus), our aim was to assess their putative introgression with the native Iberian subspecies B. terrestris lusitanicus. We analysed one mitochondrial gene, cytochrome c oxidase subunit I (COX1) and genomic data involving thousands of genome‐wide restriction‐site‐associated DNA markers (RAD‐seq). In the mitochondrial COX1 analyses, we detected one relatively common haplotype in commercial bumblebees, also present in wild samples collected nearby the greenhouses where the commercial hives are used. In the RAD‐seq analysis, we found a clear genetic differentiation between native and commercial lineages. Furthermore, we detected candidate hybrids in the wild, as well as putatively escaped commercial bumblebees, some of which being potentially fertile males. Although we cannot assess directly the fitness effects of introgressed alleles, there is a risk of maladaptive allele introgression to the local bumblebee subspecies, which can negatively impact autochthon populations. One immediate recommendation to farmers is for the proper disposal of hive boxes, after their use in greenhouses, so as to minimize the risk of escapees contaminating native populations. On the other hand, the feasibility of using local subspecies B. t. lusitanicus, preferably with local production, should be evaluated. [ABSTRACT FROM AUTHOR]

Experimental evolution is a powerful tool to understand the adaptive potential of populations under environmental change. Here, we study the importance of the historical genetic background in the outcome of evolution at the genomewide level. Using the natural clinal variation of Drosophila subobscura, we sampled populations from two contrasting latitudes (Adraga, Portugal and Groningen, Netherlands) and introduced them in a new common environment in the laboratory. We characterized the genome-wide temporal changes underlying the evolutionary dynamics of these populations, which had previously shown fast convergence at the phenotypic level, but not at chromosomal inversion frequencies. We found that initially differentiated populations did not converge either at genome-wide level or at candidate SNPs with signs of selection. In contrast, populations from Portugal showed convergence to the control population that derived from the same geographical origin and had been long-established in the laboratory. Candidate SNPs showed a variety of different allele frequency change patterns across generations, indicative of an underlying polygenic basis. We did not detect strong linkage around candidate SNPs, but rather a small but longranging effect. In conclusion, we found that history played a major role in genomic variation and evolution, with initially differentiated populations reaching the same adaptive outcome through different genetic routes. [ABSTRACT FROM AUTHOR]

The tiger-fly Coenosia attenuata is a globally widespread predatory fly which is not only associated with greenhouse crops, but also occurs in open fields. It is a potential control agent against some of the more common pests in these crops. Assessing the genetic structure and gene flow patterns may be important for planning crop protection strategies and for understanding the historical processes that led to the present distribution of genetic lineages within this species. In the present study, the phylogeographical patterns of this species, based on mitochondrial cytochrome oxidase I and nuclear white and elongation factor-1α genes, are described, revealing relatively low genetic diversity and weak genetic structure associated with a recent and sudden population expansion of the species. The geographical distribution of mitochondrial haplotypes indicates the Mediterranean as the most likely region of origin of the species. Some dispersal patterns of the species are also revaled, including at least three independent colonizations of North and South America: one from Middle East to North America with a strong bottleneck event, another from Europe to South America ( Chile), with both likely to be a result of unintentional introduction, and a third one of still undetermined origin to South America ( Ecuador). © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114, 308-326. [ABSTRACT FROM AUTHOR]

Philaenus spumarius is a widespread insect species in the Holarctic region. Here, by focusing on the mtDNA gene COI but also using the COII and Cyt b genes and the nuclear gene EF-1α, we tried to explain how and when its current biogeographic pattern evolved by providing time estimates of the main demographic and evolutionary events and investigating its colonization patterns in and out of Eurasia. Evidence of recent divergence and expansion events at less than 0.5 Ma ago indicate that climate fluctuations in the Mid-Late Pleistocene were important in shaping the current phylogeographic pattern of the species. Data support a first split and differentiation of P. spumarius into two main mitochondrial lineages: the “western”, in the Mediterranean region and the “eastern”, in Anatolia/Caucasus. It also supports a following differentiation of the “western” lineage into two sub-lineages: the “western-Mediterranean”, in Iberia and the “eastern-Mediterranean” in the Balkans. The recent pattern seems to result from postglacial range expansion from Iberia and Caucasus/Anatolia, thus not following one of the four common paradigms. Unexpected patterns of recent gene-flow events between Mediterranean peninsulas, a close relationship between Iberia and North Africa, as well as high levels of genetic diversity being maintained in northern Europe were found. The mitochondrial pattern does not exactly match to the nuclear pattern suggesting that the current biogeographic pattern of P. spumarius may be the result of both secondary admixture and incomplete lineage sorting. The hypothesis of recent colonization of North America from both western and northern Europe is corroborated by our data and probably resulted from accidental human translocations. A probable British origin for the populations of the Azores and New Zealand was revealed, however, for the Azores the distribution of populations in high altitude native forests is somewhat puzzling and may imply a natural colonization of the archipelago. [ABSTRACT FROM AUTHOR]

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DNA barcodes have great potential to assist in species identification, especially when high taxonomical expertise is required. We investigated the utility of the 5′ mitochondrial cytochrome c oxidase I ( COI) region to discriminate between 13 European cicada species. These included all nine species currently recognized under the genus Tettigettalna, from which seven are endemic to the southern Iberian Peninsula. These cicadas have species-specific male calling songs but are morphologically very similar. Mean COI divergence between congeners ranged from 0.4% to 10.6%, but this gene was proven insufficient to determine species limits within genus Tettigettalna because a barcoding gap was absent for several of its species, that is, the highest intraspecific distance exceeded the lowest interspecific distance. The genetic data conflicted with current taxonomic classification for T. argentata and T. mariae. Neighbour-joining and Bayesian analyses revealed that T. argentata is geographically structured (clades North and South) and might constitute a species complex together with T. aneabi and T. mariae. The latter diverges very little from the southern clade of T. argentata and shares with it its most common haplotype. T. mariae is often in sympatry with T. argentata but it remains unclear whether introgression or incomplete lineage sorting may be responsible for the sharing of haplotypes. T. helianthemi and T. defauti also show high intraspecific variation that might signal hidden cryptic diversity. These taxonomic conflicts must be re-evaluated with further studies using additional genes and extensive morphological and acoustic analyses. [ABSTRACT FROM AUTHOR]

The occurrence of polyandry in Planococcus citri, presumed by earlier observations of mating behavior, was confirmed using microsatellite genotyping of pools of over 400 eggs resulting from controlled crosses of one female with two males. The genetic contribution of both mated males was confirmed in 13 out of 43 crosses. In three crosses it was possible to determine that only the first male fertilized the eggs, which may be due to sperm competition or unviable sperm supply. The microsatellite analysis also allowed the confirmation of aspects of the chromosomal inheritance detected previously in cytogenetic studies in Planococcus citri, namely that only one of the alleles is transmitted by the male, indicating that the males are functionally haploid, supporting the observation of Paternal Genome Elimination (PGE) in these insects. [ABSTRACT FROM AUTHOR]

The small cicada Tettigettalnajosei (Boulard, 1982) was until recently only known from southern Portugal and was considered endemic to this country. Fieldwork in 2013 led to the first record of the species in Spain, expanding its known eastern range to Andalusia. The northern limits remain poorly defined but it appears that the distribution of Tettigettalnajosei is restricted to the south Atlantic coastline in the Iberian Peninsula, with the highest densities found in Algarve. Some notes on behaviour and genetic variation of Tettigettalnajosei are also given.