Jenny Hagenblad

Crop wild relatives (CWR) are wild plant taxa that are closely related to crops and other cultivated species. The importance of conserving CWR genetic diversity as a valuable source of variation for plant breeding has been regularly brought forward, and knowledge about the distribution of genetic diversity within and among natural populations can aid in efficient conservation and increased availability of CWR genetic resources. Within the Nordic countries (Iceland, Norway, Denmark, Sweden and Finland), the European wild strawberry, Fragaria vesca L., has been recognized as a CWR of priority. However, information about the distribution of its within- and among-population genetic diversity in the Nordic countries is limited. In total, 180 individuals from twelve populations covering the majority of the Nordic range of F. vesca were genotyped with 14 microsatellite markers. Overall, populations had high inbreeding coefficient F _IS values, although a large variation was observed across the region. In agreement with expectations, populations from higher latitudes tended to have less genetic diversity and a higher presence of genetically identical individuals, possibly the result of clonal propagation. The analysis of molecular variance (AMOVA) showed that genetic diversity was primarily distributed among populations within countries, supporting a regional conservation approach. Analysis of the geographic distribution of the genetic diversity with STRUCTURE and principal component analyses and calculation of pairwise F _ST values revealed that the studied individuals formed clusters which partially, but not completely, corresponded to the geographical origin of the populations. The inclusion of multiple individuals per populations allowed geographic clustering to be detected on a finer scale than previously described. Ex situ conservation of F. vesca is recommended mainly to improve availability of these genetic resources for research and breeding and based on the within- and among-population distribution of genetic diversity, prioritizations are suggested.

Aim: Widespread species encounter a range of variable climates that can lead to intraspecific trait clines. Such clines can be the result of phenotypic plasticity, genetic differences, or both. Although latitude often explains a large part of trait variation, it is crucial to investigate the underlying environmental variables to understand current and future trait responses. Cross‐continental comparisons of species that are native on multiple continents provide a rarely used approach that can help identify the environmental drivers of intraspecific trait clines. Location: Europe and North America. Time Period: 2021–2023. Major Taxa Studied: Milium effusum L. (Poaceae). Methods: To quantify the influence of environmental gradients on functional traits across geographical regions that vary in climate, we sampled M. effusum seeds from 23 European and 14 North American populations and transplanted them in a common garden. We measured 10 vegetative, reproductive, and phenological traits. We used 30‐year averages of 19 bioclimatic variables, while accounting for the latitudinal and elevational position of the population origins, to compare the trait‐environment relationships between continents. Results: Our results showed that European populations occupy a broader climatic range than North American populations. Differences between continents were found in most of the traits as well as in the multivariate trait space. The traits were affected more by bioclimatic variables than by latitude or elevation. While flowering, leaf thickness, specific leaf area, and reproductive height showed parallel clines to the environment between continents, vegetative height and biomass showed contrasting clines. Main Conclusions: Environmental influences from population origins revealed parallel clines between the continents for functional traits, suggesting shared selective pressures, while contrasting clines for plant size indicated different evolutionary trajectories, potential bottlenecks, or interactions with unknown ecological factors. This study highlights the complex interplay of genetic, environmental, and evolutionary factors in shaping phenotypic variation in native species across continents.

Urban areas can support diverse communities of plants and animals. Yet, urbanisation can affect functionally important species traits, potentially impacting population dynamics. The saproxylic beetle Elater ferrugineus L. is associated with large trees and is often used as an indicator of species‐rich saproxylic communities. It is an important target for conservation and it is listed as a near‐threatened species on the European Red List. Few studies have quantified the impact of urbanisation on the ecology and intraspecific variation in functional traits of arthropods, other than pollinators. We studied how the local abundance of E. ferrugineus and functionally important response traits (e.g., width of the pronotum, length of the elytron and wing, wing area, body mass and wingload) changed along urbanisation gradients in eight European cities using pheromone traps installed on large solitary trees. We analysed the effects of the surrounding built‐up area and tree cover on our response variables while accounting for potential confounding effects due to tree size and the availability of microhabitats. Urbanisation had a strong negative effect on the local abundance of E. ferrugineus , while the amount of tree cover had a positive influence. We found no significant impact of urbanisation on the functional traits of this species, except for a significantly higher wingload in city centres. Our results provide a better understanding of the ecological processes impacting this saproxylic beetle and underpin the importance of future research on urbanisation's impact on arthropods.

The current global crisis of biodiversity loss calls for urgent conservation actions for many species, not the least wild species related to crop plants. These crop wild relatives are considered harbouring genetic diversity of major importance for future crop plant improvement, e.g. adaptation to climate change. Hence, their conservation needs to be a priority. To ensure the long-term conservation and to maximize the utility value of these species, it is important that as much of their genetic diversity as possible is conserved. Thus, the distribution of intraspecific diversity must be taken into consideration when planning conservation efforts. Caraway, Carum carvi L., has been cultivated since medieval times and is today one of the most important spice crops worldwide. In order to identify populations that would be of particular interest for in situ and ex situ conservation and for use in plant breeding we evaluated the geographic distribution of intraspecific diversity in populations of Carum carvi in the Nordic region (Iceland, Denmark, Norway, Sweden and Finland). Using a genotyping by sequencing approach, we genotyped 198 individuals from 16 Nordic populations. The amount of intrapopulation genetic diversity was similar among populations (mean H_e = 0.29), and the diversity was structured in an east–westerly manner, probably reflecting colonisation patterns associated with different glacial refugia. In addition, some populations likely have a history shaped by human interventions. The results have important conservation implications and based on the outcome of this study, populations of conservation priority are suggested.

The human colonization of the Canary Islands represents the sole known expansion of Berber communities into the Atlantic Ocean and is an example of marine dispersal carried out by an African population. While this island colonization shows similarities to the populating of other islands across the world, several questions still need to be answered before this case can be included in wider debates regarding patterns of initial colonization and human settlement, human–environment interactions, and the emergence of island identities. Specifically, the chronology of the first human settlement of the Canary Islands remains disputed due to differing estimates of the timing of its first colonization. This absence of a consensus has resulted in divergent hypotheses regarding the motivations that led early settlers to migrate to the islands, e.g., ecological or demographic. Distinct motivations would imply differences in the strategies and dynamics of colonization; thus, identifying them is crucial to understanding how these populations developed in such environments. In response, the current study assembles a comprehensive dataset of the most reliable radiocarbon dates, which were used for building Bayesian models of colonization. The findings suggest that i) the Romans most likely discovered the islands around the 1st century BCE; ii) Berber groups from western North Africa first set foot on one of the islands closest to the African mainland sometime between the 1st and 3rd centuries CE; iii) Roman and Berber societies did not live simultaneously in the Canary Islands; and iv) the Berber people rapidly spread throughout the archipelago.

Introduction: In situ and ex situ conservation are the two main approaches for preserving genetic diversity. The advantages and disadvantages of the two approaches have been discussed but their genetic effects have not been fully evaluated.Methods: In this study we investigate the effects of the two conservation approaches on genetic diversity in red clover. Seed samples collected from wild populations in Sweden and Norway in 1980, their subsequent generations created during seed regeneration at the gene bank and samples recollected from the same location as the original samples, were analyzed with microsatellite markers, alongside reference samples from cultivars.Results: Overall, there was a differentiation between cultivars and the wild material and between wild material from Sweden and Norway. In general, the original collections clustered together with the later generations of the same accession in the gene bank, and with the recollected samples from the same location, and the level of diversity remained the same among samples of the same accession. Limited gene flow from cultivated varieties to the wild populations was detected; however, some wild individuals are likely to be escapees or affected by gene flow.Discussion: In conclusion, there were examples of genetic changes within individual accessions both in situ and ex situ, as is also to be expected in any living population. However, we observed only limited genetic changes in both in situ and ex situ conservation over the generations included in this study and with the relatively large populations used in the ex situ conservation in the gene bank at NordGen.