Restricted Gene Flow Research Articles

Genetic diversity and population structure of Moroccan Botrytis spp. strains, causing chocolate spot disease in faba bean

Chocolate spot (Botrytis spp.) is one of the most important foliar diseases limiting the yield and seed quality of faba bean (Vicia faba L.) worldwide. Knowledge of the population structure of the pathogen is key to developing appropriate breeding strategies for disease management. This study aims to assess the genetic diversity and population structure of 75 Botrytis spp. isolates collected from seven major faba bean growing regions in Morocco. Genetic diversity was assessed using 30 Sequence Related Amplified Polymorphism (SRAP) primer combinations. Eight primer-combinations generated 118 polymorphic alleles and had discriminated between different isolates with an average PIC value of 0.28. The Moroccan Botrytis spp. populations presented a high genetic diversity that was more distributed within populations (99%) than among populations. Population structure analysis revealed that the genetic diversity was not linked to geographic locations, indicating limited geographic delimitation and significant gene flow. The data will be useful to improve the faba bean breeding program to develop effective resistant cultivars. To our knowledge, this is the first study carried out on the genetic variability of Botrytis spp. Isolates from faba bean In Morocco.

Genetic Diversity on a Rare Terrestrial Orchid, Habenaria linearifolia in South Korea: Implications for Conservation Offered by Genome-Wide Single Nucleotide Polymorphisms.

Monitoring intraspecific diversity offers invaluable insights on conservation practices as the variation is the product of species evolution. Accordingly, the role of population genetic diversity has drawn great attention over the last century responding to the biodiversity loss induced by a series of anthropogenic changes. Orchids are one of the most diverse, yet ironically most rapidly disappearing plant groups due to the specialized habitat preferences. Thus, population-level genetic diversity studies may offer a powerful tool for orchid conservation programs. Using the 3 restriction site-associated DNA (3RAD) approach, 2,734 genome-wide single nucleotide polymorphisms (SNPs) were isolated. With the 2,734 SNPs, we investigated genetic diversity and population structure on 72 individuals of Habenaria linearifolia and Habenaria cruciformis in South Korea. Overall, the genetic diversity was well maintained in South Korean Habenaria, but high FST values were estimated suggesting large population diversification with limited gene flow. Bayesian assignment analysis revealed a morphologically cryptic diversity pattern in Jeju Island populations, which might serve as an evolutionarily significant unit.

Genetic structure of the endemic Dipterocarpus condorensis revealed by microsatellite markers.

Anthropogenic disturbances in tropical forests often affect the genetic diversity of a species. Dipterocarpus condorensis is an endangered species in the tropical forests of south-eastern Vietnam, both from its over-exploitation and habitat loss. Therefore, knowledge of population genetic diversity and population structure is essential for identifying the species conservation measures. In the present study, we evaluated genetic diversity and population structure using nine microsatellites for 183 individual trees from eight populations, representing the distribution range of D. condorensis in Vietnam. Two clustering approaches (Bayesian analysis and discriminant analysis of principal components) revealed that all studied individuals clustered into three genetic groups, which were related to gene flow across the range of D. condorensis in the lowland tropical forests of south-eastern Vietnam. Limited gene flow was implicated in anthropogenic disturbance. Genetic differentiation among populations was relatively low (the Weir and Cockerham index of 0.122 and the Hedrick index of 0.149) and showed significant differentiation. The genetic variability of the populations was low (HO = 0.298 and HE = 0.324), which suggested the negative effects of habitat degradation and over-exploitation. Our studies also determined that D. condorensis populations can have undergone recent bottlenecks. We recommend conservation activities for this species based on these results.

Ancient DNA and deep population structure in sub-Saharan African foragers

Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa1–4. Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations3,5. Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80–20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch.

Population Genetic Structure and Biodiversity Conservation of a Relict and Medicinal Subshrub Capparis spinosa in Arid Central Asia

As a Tertiary Tethyan relict, Capparis spinosa is a typical wind-preventing and sand-fixing deciduous subshrub in arid central Asia. Due to its medicinal and energy value, this species is at risk of potential threat from human overexploitation, habitat destruction and resource depletion. In this study, our purpose was to evaluate the conservation strategies of C. spinosa according to its genetic structure characteristics and genetic diversity pattern among 37 natural distributional populations. Based on genomic SNP data generated from dd-RAD sequencing, genetic diversity analysis, principal component analysis, maximum likelihood phylogenetic trees and ADMIXTURE clustering, the significant population structure and differentiation were explored. The results showed the following: (1) Six distinct lineages were identified corresponding to geographic locations, and various levels of genetic diversity existed among the lineages for the natural habitat heterogeneity or human interferences; (2) The lineage divergences were influenced by isolation by distances, vicariance and restricted gene flow under complex topographic and climatic conditions. Finally, for the preservation of the genetic integrity of C. spinosa, we suggest that conservation units should be established corresponding to different geographic groups, and that attention should be paid to isolated and peripheral populations that are experiencing biodiversity loss. Simultaneously, monitoring and reducing anthropogenic disturbances in addition to rationally and sustainably utilizing wild resources would be beneficial to guarantee population resilience and evolutionary potential of this xerophyte in response to future environmental changes.

Structured phylogeography and restricted gene flow among populations of Fairy Tern (Sternula nereis) across Australasia: implications for the endangered New Zealand population

The Fairy Tern Sternula nereis is an Australasian tern that breeds in Australia, New Caledonia and New Zealand, with the last having the smallest breeding population, listed as ‘Threatened – Nationally Critical’ by the New Zealand Department of Conservation. Here, we investigate the genetic relatedness and level of endemism (gene flow) of the New Zealand Fairy Tern S. n. davisae population compared with the larger breeding populations in Australia, S. n. nereis, and New Caledonia, S. n. exsul, using the NADH subunit 2 (ND2) region of the mitochondrial DNA. We found that the three main populations (n = 86) were genetically distinct, with a different fixed haplotype restricted to New Zealand (n = 15) and New Caledonia (n = 16), and that the estimated gene flow was low to zero, indicating no interbreeding between the populations. The current genetic evidence is consistent with observations of morphological and behavioural differences among the populations, and we suggest continued independent management of the population in New Zealand and further surveys and independent management of the New Caledonia population.

Assessing Population Genetic Status for Designing Plant Translocations

Assisted gene flow interventions such as plant translocations are valuable complementary techniques to habitat restoration. Bringing new genetic variants can contribute to increasing genetic diversity and evolutionary resilience, counteract inbreeding depression and improve plant fitness through heterosis. Large, highly genetically variable populations are usually recommended as sources for translocation. Unfortunately, many critically endangered species only occur as small populations, which are expected to show low genetic variation, high inbreeding level, paucity of compatible mates in self-incompatible species, and increased genetic divergence. Therefore, assessment of population genetic status is required for an appropriate choice of the source populations. In this paper, we exemplify the different analyses relevant for genetic evaluation of populations combining both molecular (plastid and nuclear) markers and fitness-related quantitative traits. We assessed the genetic status of the adult generation and their seed progeny (the potential translocation founders) of small populations of Campanula glomerata (Campanulaceae), a self-incompatible insect-pollinated herbaceous species critically endangered in Belgium. Only a few small populations remain, so that the species has been part of a restoration project of calcareous grasslands implementing plant translocations. In particular, we estimated genetic diversity, inbreeding levels, genetic structure in adults and their seed progeny, recent bottlenecks, clonal extent in adults, contemporary gene flow, effective population size (Ne), and parentage, sibship and seed progeny fitness variation. Small populations of C. glomerata presented high genetic diversity, and extensive contemporary pollen flow within populations, with multiple parentage among seed progenies, and so could be good seed source candidates for translocations. As populations are differentiated from each other, mixing the sources will not only optimize the number of variants and of compatible mates in translocated populations, but also representativeness of species regional genetic diversity. Genetic diversity is no immediate threat to population persistence, but small Ne, restricted among-population gene flow, and evidence of processes leading to genetic erosion, inbreeding and inbreeding depression in the seed progeny require management measures to counteract these trends and stochastic vulnerability. Habitat restoration facilitating recruitment, flowering and pollination, reconnecting populations by biological corridors or stepping stones, and creating new populations through translocations in protected areas are particularly recommended.

Phylogeography of the Neotropical sciurid Guerlinguetus brasiliensis (Rodentia: Sciuridae)

Abstract The Brazilian squirrel Guerlinguetus brasiliensis is the only sciurid species occurring in the Atlantic Forest. We investigated the geographical distribution of the genetic diversity of this sciurid species across the Central Corridor of the Atlantic Forest, using two mitochondrial markers and one nuclear marker. We also inferred the demographic history and estimated the present and past habitat suitability for the species. We found strong mitochondrial DNA structure, possibly with both the Doce River and the valley of Paraíba do Sul River restricting gene flow between populations. The demography and ecological niche modelling highlighted a shared evolutionary history amongst several forest-dependent species in the Atlantic Forest. A pattern of isolation by distance was also found, revealing the low mobility and/or dispersal capacity of the species. Further data are required to disentangle exactly how past and/or recent habitat changes have affected population-level genetic diversity of G. brasiliensis.

The role of mitonuclear incompatibilities in allopatric speciation.

Aerobic metabolism in eukaryotic cells requires extensive interactions between products of the nuclear and mitochondrial genomes. Rapid evolution of the mitochondrial genome, including fixation of both adaptive and deleterious mutations, creates intrinsic selection pressures favoring nuclear gene mutations that maintain mitochondrial function. As this process occurs independently in allopatry, the resulting divergence between conspecific populations can subsequently be manifest in mitonuclear incompatibilities in inter-population hybrids. Such incompatibilities, mitonuclear versions of Bateson-Dobzhansky-Muller incompatibilities that form the standard model for allopatric speciation, can potentially restrict gene flow between populations, ultimately resulting in varying degrees of reproductive isolation. The potential role of mitonuclear incompatibilities in speciation is further enhanced where mtDNA substitution rates are elevated compared to the nuclear genome and where population structure maintains allopatry for adequate time to evolve multiple mitonuclear incompatibilities. However, the fact that mitochondrial introgression occurs across species boundaries has raised questions regarding the efficacy of mitonuclear incompatibilities in reducing gene flow. Several scenarios now appear to satisfactorily explain this phenomenon, including cases where differences in mtDNA genetic load may drive introgression or where co-introgression of coadapted nuclear genes may support the function of introgressed mtDNA. Although asymmetries in reproductive isolation between taxa are consistent with mitonuclear incompatibilities, interactions between autosomes and sex chromosomes yield similar predictions that are difficult to disentangle. With regard to establishing reproductive isolation while in allopatry, existing studies clearly suggest that mitonuclear incompatibilities can contribute to the evolution of barriers to gene flow. However, there is to date relatively little definitive evidence supporting a primary role for mitonuclear incompatibilities in the speciation process.

Molecular ecology of a shallow water shrimp, Acetes sibogae sibogae Hansen 1919: Evidence for strongly limited gene flow across the western Pacific

AbstractThe shallow water shrimp Acetes sibogae sibogae is an ecological and economically important organism in the Asian region. We assessed the genetic diversity and population structure of this species based on samples obtained from eight sites in Japan, the Philippines and Indonesia. Nucleotide sequence analyses were performed based on PCR‐amplified mitochondrial DNA fragments comprising the control region and part of the 12S rRNA gene. In total, 656 bp nucleotide sequences were obtained from 377 individuals. The results show a low haplotype diversity value in shrimp from the Kokuba‐gawa River (0.5) in Japan and intermediate values (0.79–0.99) in other populations. While nucleotide diversity estimates in all sampled localities were lower (0.17%–0.86%) than those reported in other crustaceans, analysis of molecular variance revealed significant genetic differentiation (p < .001) among all sites. Furthermore, the mean fixation index estimate was very high (FST: 0.27), indicating that dispersal potential among sites was low and gene flow, therefore, was restricted. The mismatch distribution of pairwise differences between haplotypes indicated that A. s. sibogae did not fit a sudden population expansion model. Overall, the present study indicates that wild stocks of A. s. sibogae on Okinawa‐jima Island and the Philippine and Indonesian Archipelagos should be assigned high importance for conservation management of this species because adapted genotypes have significant evolutionary potential during environmental changes.[Correction added on 5th February 2022, after first online publication: Values have been corrected in the Abstract section.]

Strong spatial population structure shapes the temporal coevolutionary dynamics of costly female preference and male display

Female mating preferences for exaggerated male display traits are commonplace. Yet, comprehensive understanding of the evolution and persistence of costly female preference through indirect (Fisherian) selection in finite populations requires some explanation for the persistence of additive genetic variance (V a) underlying sexual traits, given that directional preference is expected to deplete V a in display and hence halt preference evolution. However, the degree to which V a, and hence preference‐display coevolution, may be prolonged by spatially variable sexual selection arising solely from limited gene flow and genetic drift within spatially structured populations has not been examined. Our genetically and spatially explicit model shows that spatial population structure arising in an ecologically homogeneous environment can facilitate evolution and long‐term persistence of costly preference given small subpopulations and low dispersal probabilities. Here, genetic drift initially creates spatial variation in female preference, leading to persistence of V a in display through “migration‐bias” of genotypes maladapted to emerging local sexual selection, thus fueling coevolution of costly preference and display. However, costs of sexual selection increased the probability of subpopulation extinction, limiting persistence of high preference‐display genotypes. Understanding long‐term dynamics of sexual selection systems therefore requires joint consideration of coevolution of sexual traits and metapopulation dynamics.

Genetic continuity of Indo-Iranian speakers since the Iron Age in southern Central Asia

Since prehistoric times, southern Central Asia has been at the crossroads of the movement of people, culture, and goods. Today, the Central Asian populations are divided into two cultural and linguistic groups: the Indo-Iranian and the Turko-Mongolian groups. Previous genetic studies unveiled that migrations from East Asia contributed to the spread of Turko-Mongolian populations in Central Asia and the partial replacement of the Indo-Iranian populations. However, little is known about the origin of the latters. To shed light on this, we compare the genetic data on two current-day Indo-Iranian populations — Yaghnobis and Tajiks — with genome-wide data from published ancient individuals. The present Indo-Iranian populations from Central Asia display a strong genetic continuity with Iron Age samples from Turkmenistan and Tajikistan. We model Yaghnobis as a mixture of 93% Iron Age individual from Turkmenistan and 7% from Baikal. For the Tajiks, we observe a higher Baikal ancestry and an additional admixture event with a South Asian population. Our results, therefore, suggest that in addition to a complex history, Central Asia shows a remarkable genetic continuity since the Iron Age, with only limited gene flow.

Weak population spatial genetic structure and low infraspecific specificity for fungal partners in the rare mycoheterotrophic orchid Epipogium aphyllum

Some plants abandoned photosynthesis and developed full dependency on fungi for nutrition. Most of the so-called mycoheterotrophic plants exhibit high specificity towards their fungal partners. We tested whether natural rarity of mycoheterotrophic plants and usual small and fluctuating population size make their populations more prone to genetic differentiation caused by restricted gene flow and/or genetic drift. We also tested whether these genetic characteristics might in turn shape divergent fungal preferences. We studied the mycoheterotrophic orchid Epipogium aphyllum, addressing the joint issues of genetic structure of its populations over Europe and possible consequences for mycorrhizal specificity within the associated fungal taxa. Out of 27 sampled E. aphyllum populations, nine were included for genetic diversity assessment using nine nuclear microsatellites and plastid DNA. Population genetic structure was inferred based on the total number of populations. Individuals from 17 locations were included into analysis of genetic identity of mycorrhizal fungi of E. aphyllum based on barcoding by nuclear ribosomal DNA. Epipogium aphyllum populations revealed high genetic diversity (uHe = 0.562) and low genetic differentiation over vast distances (FST = 0.106 for nuclear microsatellites and FST = 0.156 for plastid DNA). Bayesian clustering analyses identified only two genetic clusters, with a high degree of admixture. Epipogium aphyllum genets arise from panmixia and display locally variable, but relatively high production of ramets, as shown by a low value of rarefied genotypic richness (Rr = 0.265). Epipogium aphyllum genotype control over partner selection was negligible as (1) we found ramets from a single genetic individual associated with up to 68% of the known Inocybe spp. associating with the plant species, (2) and partner identity did not show any geographic structure. The absence of mosaicism in the mycorrhizal specificity over Europe may be linked to preferential allogamous habit of E. aphyllum and significant gene flow, which tend to promote host generalism.

Comparative population genomics reveals glacial cycles to drive diversifications in tropical montane birds (Aves, Timaliidae)

Many bird species are specialized to live in the broadleaved, evergreen forests in the mountain regions in Southeast Asia. These mountain habitats are not continuously distributed as the different mountain areas are separated by lowlands, which has restricted gene flow and thus contributed to the high biological diversity in this region. The degree of connectivity between mountain areas has fluctuated with the Pleistocene glacial cycles, being largest during the glaciations when the mountain forests spread to lower elevations. Here we study how the intermittent periods of restricted gene flow and connectivity between the populations of five montane species of babblers (Aves, Timaliidae) in Vietnam may be traced in their genomes. The results suggest that the babbler species in the Central Highlands have been isolated from their sister-populations in northern Vietnam for between ca. 585 and 380 ky. For two species with populations in both the Central Highlands and the Da Lat region, we found that these split at more or less the same time (440–340 kya). We also found a significant statistical correlation between the time of the splits of these populations and the lowest altitude at which they are known to occur (no similar correlation was found with the geographic distances between populations). The populations in northern Vietnam show higher genetic variation than their counterparts in South-Central Vietnam, supporting the postulate that smaller populations may have lower genetic variation than larger. In accordance with this, we found the lowest genetic variation in the two species with the smallest populations in the Central Highlands. These two populations also show low levels of genomic heterozygosity. Our results show that the south-central populations of the studied babbler species are genetically distinct from their sister-populations in northern Vietnam, providing additional argument for the long-term protection of the evergreen mountain forests in Southeast Asia.

Phylogeographic Structure within the Fiddler Crabs Leptuca thayeri and Uca maracoani (Brachyura, Ocypodidae) along the Tropical West Atlantic.

Most fiddler crabs have an extended planktonic larval phase, potentially maintaining gene flow among widely separated populations, in the absence of marine barriers. Such marine barriers could be long coastal stretches without suitable habitat, freshwater plumes caused by large river mouths, or strong currents. Typically, fiddler crabs inhabit mangrove habitats, and as mangroves tend to have a patchy distribution, it is important to gather information on the connectivity between neighboring mangroves and recognize local endemisms. To detect potential genetic differentiation among mangrove-dwelling populations of Leptuca thayeri and Uca maracoani along several thousand kilometers of a tropical coastline, mtDNA sequences of different populations from Brazil and two Caribbean islands were analyzed and compared. As shown in previous studies with fiddler crabs, Brazilian populations are genetically indiscernible, and our data suggest the absence of long-standing gene flow barriers in the two studied species along the Brazilian coast. This includes both sides of the postulated biogeographic barriers corresponding to the split of the Central South Equatorial Current and to the Amazon River freshwater plume. In contrast, conspecific individuals from the Greater Antilles carried different haplotypes, suggesting a biogeographical barrier between Brazil and the Caribbean, apparently having limited gene flow between both regions for extended time periods.

First insight of genetic diversity, phylogeographic relationships, and population structure of marine sponge Chondrosia reniformis from the eastern and western Mediterranean coasts of Tunisia.

Despite the strategic localization of Tunisia in the Mediterranean Sea, no phylogeographic study on sponges has been investigated along its shores. The demosponge Chondrosia reniformis, descript only morphologically along Tunisian coasts, was chosen to estimate the influence of natural oceanographic and biogeographic barriers on its genetic differentiation and its Phylogeography. The cytochrome oxidase subunit I (COI) gene was amplified and analyzed for 70 Mediterranean Chondrosia reniformis, collected from eight localities in Tunisia. Polymorphism results revealed high values of haplotype diversity (H d) and very low nucleotide diversity (π). Thus, these results suggest that our sponge populations of C. reniformis may have undergone a bottleneck followed by rapid demographic expansion. This suggestion is strongly confirmed by the results of neutrality tests and “mismatch distribution.” The important number of haplotypes between localities and the high genetic differentiation (F st ranged from 0.590 to 0.788) of the current C. reniformis populations could be maintained by the limited gene flow Nm (0.10–0.18). Both haplotype Network and the biogeographic analysis showed a structured distribution according to the geographic origin. C. reniformis populations are subdivided into two major clades: Western and Eastern Mediterranean. This pattern seems to be associated with the well‐known discontinuous biogeographic area: the Siculo‐Tunisian Strait, which separates two water bodies circulating with different hydrological, physical, and chemical characteristics. The short dispersal of pelagic larvae of C. reniformis and the marine bio‐geographic barrier created high differentiation among populations. Additionally, it is noteworthy to mention that the “Mahres/Kerkennah” group diverged from Eastern groups in a single sub‐clade. This result was expected, the region Mahres/Kerkennah, presented a particular marine environment.

New records of hybridisation in Australian Fairy-wrens Malurus spp.

Ornithologists have long been fascinated by avian hybrids and this interest has increased in recent years with advances in our understanding of the potential evolutionary consequences of hybridisation. To date there are only four published records of hybridisation between currently recognised species in the Australian fairy-wrens Malurus spp., including one involving limited gene flow between two closely related species. Here we present three new records of hybridisation among Australian fairy-wrens and provide further information on a previous report.

Exploring the Pocillopora cryptic diversity: a new genetic lineage in the Western Indian Ocean or remnants from an ancient one?

Cryptic species and lineages have been widely reported during the last decades, particularly in the marine realm. Misidentifications and ignoring species complexes imply many consequences, notably biasing biodiversity and connectivity assessments, which in turn mislead our understanding of ecosystems and impact the effective design and management of conservation plans. Focusing on the Indo-Pacific coral genus Pocillopora, playing key roles in reef ecosystems as one of the main bio-constructors, we report the first Pocillopora PSH16 (ORF53; sensu Gélin et al. 2017) colonies (N = 19) in the Western Indian Ocean (Nosy Tanikely, Madagascar), 6000 km further from its current distribution. Colonies were identified according to their mitochondrial open reading frame (ORF) haplotype and Bayesian assignment tests based on 13-microsatellite genotypes. Additionally, we performed genetic structure and diversity analyses with sympatric colonies from other Pocillopora species and Pocillopora PSH16 colonies from the tropical southwestern Pacific, revealing (1) a weak clonal richness, (2) a weak genetic diversity and (3) a relative isolation for the newly reported PSH16 colonies. These colonies thus represent either a new, distinct and uncommon, genetic lineage or isolated remnants of a wider one. In any case, unless specific management measures are implemented, their long-term maintenance seems compromised due to restricted gene flow within a restricted pool of genes.

Editorial 2022

Editorial 2022

Evaluating the legacy of multiple introductions of American martens on spatiotemporal patterns of genetic diversity

AbstractSpecies reintroductions are successful when established populations maintain both demographic stability and genetic diversity. Such a result may be obtained by ensuring both structural habitat connectivity and genetic connectivity among reintroduced and remnant populations. Nevertheless, prezygotic barriers such as assortative mating can prevent the flow of genetic material between populations, even when migration between populations is high. Limited gene flow may be particularly relevant for reintroductions that were sourced either from captive-bred populations or from disparate locations in the wild. American martens (Martes americana) have been reintroduced repeatedly in the Upper Midwestern United States in an effort to establish self-sustaining populations. We quantified levels of genetic diversity within and spatial genetic variance among four marten populations during two time periods separated by 10 years. Spatially informed and naïve discriminant analysis of principal components were used to assign individuals to populations. Results indicate that heterozygosity declined and inbreeding coefficients increased between the two collection periods, while genetic structure among populations also increased. Data are consistent with assortative mating contributing to reapportioning of genetic variation. Population assignment tests show that migration among populations is apparent, but admixture (based on cluster membership probabilities) is low and declined over time. Specifically, martens may be successfully dispersing between populations but a lack of admixture indicates a lack of reproductive contributions to genetic diversity by migrants. Because marten reintroductions in this region are well-documented and well-monitored, lessons can be derived from results to inform future reintroductions. We encourage a careful balance of supplementing genetic diversity via augmentation while avoiding translocation of animals from disparate populations that may result in reproductive isolation of migrants. In combination with the maintenance of a functionally connected landscape, this strategy would maximize the likelihood of a successful reintroduction in terms both of demography and genetics.