Human-mediated Translocations Research Articles

Translocations, rising populations, and phylogeographic consequences: genomic implications for conservation of introduced Aoudad (Ammotragus lervia) in the southwestern United States

Abstract Over the last century, Texas has been inundated with exotic ungulates, with as many as 67 species represented by captive and free-ranging populations. One of the most successful species to have established free-ranging populations is the Aoudad (Ammotragus lervia). Herein, we expand on previous genetic studies in Aoudad by including new genomic profiles based on double-digest restriction site-associated DNA sequencing methods with the intent of better understanding the effects of >70 years of human-mediated translocations, population expansion, and gene flow among populations. Using a range of 4,338 to 5,529 single-nucleotide polymorphisms obtained from 73 individuals that potentially represented A. l. blainei, A. l. lervia, and A. l. sahariensis, we measured genetic patterns of diversity and connectivity between source populations from California and New Mexico and resultant aoudad populations in Texas. Principal component analyses identified phylogeographically structured populations across Texas. Further, we identified a signature of isolation by distance among Texas populations. To assess geographic regions that facilitated or blocked gene flow between populations, we used estimation of effective migration surfaces, which indicated 3 barriers to movement between populations as well as connectivity among populations in close proximity. Comparison of mtDNA haplogroups and nuclear genotypes among the 3 examined subspecies were discordant, indicating that the current subspecific taxonomic classification needs refinement. Given the vulnerable status of Aoudad in their native range of northern Africa and the exponential population growth and potential competition with native ungulates in Texas, we propose that efforts to manage non-native Aoudad should strive to maintain and preserve unique genetic units while minimizing competition and other detriments to native species in Texas. Conservation efforts are especially important given the vulnerable status of Aoudad within their native range of northern Africa.

Phylogeographic Relationships Reveal the Origin of an Introduced Population of the Dalmatian Algyroides (Reptilia: Lacertidae) into Southern Italy

The genetic structure and dispersal dynamics of reptile populations are profoundly influenced by natural processes and human activities. While natural dispersal is shaped by species’ characteristics and paleogeographical features, human-mediated translocations have become increasingly prevalent, posing ecological challenges. Mitochondrial genetic markers have been pivotal in untangling invasion pathways for various species. Our study focuses on the Dalmatian Algyroides, Algyroides nigropunctatus (Duméril & Bibron, 1839), a lizard species endemic to the Balkan Peninsula, where recent observations in the Apulian region of Italy suggest an introduced population. Genetic analyses employing two mtDNA markers (16S and ND4 genes) elucidate the phylogenetic relationships of the Dalmatian Algyroides and trace the geographic origin of the introduced population. Our findings reveal areas in western Greece and southwestern Albania as the most probable areas of the source population, while we identify two previously undetected geographical lineages in the native range, highlighting the complex evolutionary history of the species in the region. Additionally, indications of potential glacial refugia and post-glacial dispersal patterns shed more light on the species’ demographic dynamics.

Anthropogenic events and responses to environmental stress are shaping the genomes of Ethiopian indigenous goats

Anthropological and biophysical processes have shaped livestock genomes over Millenia and can explain their current geographic distribution and genetic divergence. We analyzed 57 Ethiopian indigenous domestic goat genomes alongside 67 equivalents of east, west, and north-west African, European, South Asian, Middle East, and wild Bezoar goats. Cluster, ADMIXTURE (K = 4) and phylogenetic analysis revealed four genetic groups comprising African, European, South Asian, and wild Bezoar goats. The Middle Eastern goats had an admixed genome of these four genetic groups. At K = 5, the West African Dwarf and Moroccan goats were separated from East African goats demonstrating a likely historical legacy of goat arrival and dispersal into Africa via the coastal Mediterranean Sea and the Horn of Africa. FST, XP-EHH, and Hp analysis revealed signatures of selection in Ethiopian goats overlaying genes for thermo-sensitivity, oxidative stress response, high-altitude hypoxic adaptation, reproductive fitness, pathogen defence, immunity, pigmentation, DNA repair, modulation of renal function and integrated fluid and electrolyte homeostasis. Notable examples include TRPV1 (a nociception gene); PTPMT1 (a critical hypoxia survival gene); RETREG (a regulator of reticulophagy during starvation), and WNK4 (a molecular switch for osmoregulation). These results suggest that human-mediated translocations and adaptation to contrasting environments are shaping indigenous African goat genomes.

Phylogeography of Dolichophis Populations in the Aegean Region (Squamata: Colubridae) with Taxonomic Remarks

In this study, we investigate the phylogeographic patterns of Dolichophis species in the Aegean region, aiming to elucidate their genetic diversity and putative historical colonisation routes through mitochondrial and nuclear DNA data. Our findings revealed distinct phylogeographic patterns: D. caspius exhibited a higher level of haplotypes within two shallow mitochondrial lineages, contrasting with D. jugularis, which displayed lower genetic variability in the area. Additionally, we identified evidence showing possible human-mediated historical translocation of D. caspius populations to Karpathos from the Balkans mainland. The mitochondrial variability in D. jugularis remained relatively uniform across southwestern Anatolia and Dodecanese, except for Rhodes Island. The evidence from mitochondrial and nuclear data confirming the previously described morphological differentiation of the Rhodes snakes, and thus the name D. j. zinneri Cattaneo, 2012, described on the island, could be applied to this isolated population. This result addresses the first genetic view on the long-standing taxonomic uncertainties regarding the subspecies status of Rhodes D. jugularis. Our results also raise questions regarding possible historical hybridisations between D. caspius and D. jugularis in the Dodecanese islands, prompting the need for further investigation using extensive field studies and genomic approaches. Ultimately, the Aegean islands, particularly Kos and Rhodes, seem to be important sites for the evolution of these colubrid snakes and their historical dynamics.

The 10,000-year biocultural history of fallow deer and its implications for conservation policy

Over the last 10,000 y, humans have manipulated fallow deer populations with varying outcomes. Persian fallow deer (Dama mesopotamica) are now endangered. European fallow deer (Dama dama) are globally widespread and are simultaneously considered wild, domestic, endangered, invasive and are even the national animal of Barbuda and Antigua. Despite their close association with people, there is no consensus regarding their natural ranges or the timing and circumstances of their human-mediated translocations and extirpations. Our mitochondrial analyses of modern and archaeological specimens revealed two distinct clades of European fallow deer present in Anatolia and the Balkans. Zooarchaeological evidence suggests these regions were their sole glacial refugia. By combining biomolecular analyses with archaeological and textual evidence, we chart the declining distribution of Persian fallow deer and demonstrate that humans repeatedly translocated European fallow deer, sourced from the most geographically distant populations. Deer taken to Neolithic Chios and Rhodes derived not from nearby Anatolia, but from the Balkans. Though fallow deer were translocated throughout the Mediterranean as part of their association with the Greco-Roman goddesses Artemis and Diana, deer taken to Roman Mallorca were not locally available Dama dama, but Dama mesopotamica. Romans also initially introduced fallow deer to Northern Europe but the species became extinct and was reintroduced in the medieval period, this time from Anatolia. European colonial powers then transported deer populations across the globe. The biocultural histories of fallow deer challenge preconceptions about the divisions between wild and domestic species and provide information that should underpin modern management strategies.

Sustained ecological impacts of invasive crayfish following claw injury

ABSTRACT Human activities have significantly accelerated the translocation of species outside their native range with severe consequences for global biodiversity. Freshwater crayfish are a particularly successful group of invasive species, as exemplified by the increasingly widespread marbled crayfish Procambarus virginalis Lyko, 2017. A significant portion of crayfish populations has regenerating or missing claws. At the same time, claws play important roles in crayfish feeding and intraspecific interactions, altering their ability to invade new areas and impact native communities. Here, using functional response analyses, we combined laboratory experiments and modeling to investigate whether the number of claws on marbled crayfish modulates its ecological impact (focusing on predation rate) as well as its intraspecific interactions via population dynamic modeling. We found that the number of claws did not affect the marbled crayfish’s functional response type (hyperbolic type II), attack rates, or handling times when preying on chironomid larvae. Rates of partial prey consumption were overall low (<2%), and claw number had a significant effect on the partial consumption rate of prey, which tended to increase with the number of claws and prey density. The presence of multiple intraspecific predators influenced marbled crayfish non-trophic behavior, with antagonistic effects prevalent between crayfish pairs regardless of claw status. Moreover, the impact of multiple predators was prey density-dependent, with the highest levels of antagonism shown at the lowest prey density across crayfish groups. Our findings indicate that the ecological influence of invasive crayfish remains unchanged by the number of claws, highlighting the escalating, context-independent threat these species pose to freshwater ecosystems.

Bioclimatic and local drivers modulating the expansion of an introduced temperate reptile in a subtropical island

Extensive human-mediated translocation of species from their native ranges to alien environments is a trademark of the Anthropocene. Particularly in island ecosystems, established non-native species often have highly detrimental impacts on native taxa and thus the study of the drivers mediating the establishment and expansion of introduced species in areas outside their native range is crucial to delineate timely and effective mitigation measures. Species distribution models (SDMs) are widely used in invasion biology and offer great potential for the assessment of invasion risk and the identification of areas likely to be colonized by expanding alien species. Within reptiles, Gekkonidae is the second family with most introductions globally, a reflection of the group’s capacity to survive long distance dispersal events. The temperate Moorish gecko ( Tarentola mauritanica ) is native to the Mediterranean basin but has established alien populations in multiple localities throughout the word. It was first reported in the subtropical island of Madeira in 1993 and over the last three decades has colonized a substantial section of the island’s south coast. Here, we use Madeira Island as a case study to investigate the interplay between bioclimatic and local scale variables on the occurrence of T. mauritanica in areas outside its native range. We found that the species favors areas with high temperatures during the coldest month, low mean temperatures during the wettest quarter, low annual values of precipitation, and high precipitation during the driest quarter. This translates to an obvious preference for areas with more Mediterranean-like climates which in Madeira are primarily located in the south and south-eastern sections of the island. Additionally, our models predicted that some areas of the northern coast of Madeira offer suitable conditions for the gecko, although no observations have yet been recorded. Tarentola mauritanica is expanding its range in Madeira and has already colonized the nearby island of Porto Santo. It is paramount that more research is devoted to understanding the impact of this alien gecko on the island’s native species and ecosystems, and in particular on its endemic-rich arthropod communities. • The temperate gecko seeks for native-range conditions to prevail in the subtropics. • South and south-east areas of Madeira are particularly suitable for T. mauritanica. • SDMs revealed that T. mauritanica is likely to continue expanding its distribution. • Research on the potential impacts of T. mauritanica on native taxa is needed.

Population genetic structure of the Natterjack toad (Epidalea calamita) in Ireland: implications for conservation management

Molecular methods can play a crucial role in species management and conservation. Despite the usefulness of genetic approaches, they are often not explicitly included as part of species recovery plans and conservation practises. The Natterjack toad (Epidalea calamita) is regionally Red-Listed as Endangered in Ireland. The species is declining and is now present at just seven sites within a highly restricted range. This study used 13 highly polymorphic microsatellite markers to analyse the population genetic diversity and structure. Genetic diversity was high with expected heterozygosity between 0.55 and 0.61 and allelic richness between 4.77 and 5.92. Effective population sizes were small (Ne < 100 individuals), but not abnormal for pond breeding amphibians. However, there was no evidence of historical or contemporary genetic bottlenecks or high levels of inbreeding. We identified a positive relationship between Ne and breeding pond surface area, suggesting that environmental factors are a key determinant of population size. Significant genetic structuring was detected throughout the species’ range, and we identified four genetic entities that should be considered in the species’ conservation strategies. Management should focus on preventing further population declines and future loss of genetic diversity overall and within genetic entities while maintaining adequate local effective population size through site-specific protection, human-mediated translocations and head-start programs. The apparent high levels of genetic variation give hope for the conservation of Ireland’s rarest amphibian if appropriately protected and managed.

Fresh start after rough rides: understanding patterns of genetic differentiation upon human-mediated translocations

Fresh start after rough rides: understanding patterns of genetic differentiation upon human-mediated translocations

Human exposure to larvae of processionary moths in France: study of symptomatic cases registered by the French poison control centres between 2012 and 2019

Context Contact with the setae of larvae (caterpillars) of pine or oak processionary moths could induce urticarial or allergic reactions in humans. These species are present in France and presently expanding towards highly populated areas due to climate change and/or human-mediated translocations. We aimed to describe the symptomatic cases of exposure to processionary larvae in France. Methods We conducted a retrospective study of symptomatic cases of exposure to processionary larvae registered by the French poison control centres between 1 January 2012 and 31 July 2019. We reviewed all medical records coded with the agent “larvae”. Results Of the 1274 included cases, 59% and 27% corresponded to pine and oak processionary larvae, respectively; the 14% remaining cases concerned unspecified processionary larvae. While the annual number of cases due to pine processionary larvae fluctuated during the study period, cases associated with oak processionary larvae increased steadily. Most of the annual cases occurred between January and May for pine processionary larvae, and April and August for oak processionary larvae (with a peak in March or June, respectively). Among the 1022 cases for which information was available, the sex ratio was 1.2 and the median age was 11 years old. Skin symptoms were reported by 96,3% of the cases, such as pruritus or urticaria. The severity was mild in 96.3% of cases, moderate in 3.5%, and severe in 0.2% (two cases). Ocular or oral exposures led more frequently to severe symptoms than dermal ones (respectively 31% and 18% vs. 2% of cases, p < 10−3). Conclusion Since processionary moth larvae exposure is a growing health concern, which can cause severe injuries particularly after ocular or oral exposures, the population, and the professionals should be informed of existing recommendations to avoid exposure and measures to be taken after being exposed.

Global population genetic structure and demographic trajectories of the black soldier fly, Hermetia illucens

BackgroundThe black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents.ResultsWe identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data revealed genetic hotspots in central South America and successive northwards range expansions within the indigenous ranges of the Americas. Colonisations and naturalisations of largely unique genetic profiles occurred on all non-native continents, either preceded by demographically independent founder events from various single sources or involving admixture scenarios. A decisive primarily admixed Polynesian bridgehead population serially colonised the entire Australasian region and its secondarily admixed descendants successively mediated invasions into Africa and Europe. Conversely, captive populations from several continents traced back to a single North American origin and exhibit considerably reduced genetic diversity, although some farmed strains carry distinct genetic signatures. We highlight genetic footprints characteristic of progressing domestication due to increasing socio-economic importance of H. illucens, and ongoing introgression between domesticated strains globally traded for large-scale farming and wild populations in some regions.ConclusionsWe document the dynamic population genetic history of a cosmopolitan dipteran of South American origin shaped by striking geographic patterns. These reflect both ancient dispersal routes, and stochastic and heterogeneous anthropogenic introductions during the last century leading to pronounced diversification of worldwide structure of H. illucens. Upon the recent advent of its agronomic commercialisation, however, current human-mediated translocations of the black soldier fly largely involve genetically highly uniform domesticated strains, which meanwhile threaten the genetic integrity of differentiated unique local resources through introgression. Our in-depth reconstruction of the contemporary and historical demographic trajectories of H. illucens emphasises benchmarking potential for applied future research on this emerging model of the prospering insect-livestock sector.

Extinct insular oryzomyine rice rats (Rodentia: Sigmodontinae) from the Grenada Bank, southern Caribbean.

The Lesser Antillean island chain in the eastern Caribbean formerly supported a diverse rodent fauna including multiple endemic genera of oryzomyine rice rats. The Caribbean rice rats are now all extinct, with most island populations known only from Holocene palaeontological and zooarchaeological material and with many remaining taxonomically undescribed. Rice rat material is reported from several pre-Columbian Ceramic Age (late Holocene) archaeological sites on the Grenada Bank, including sites on Grenada and Carriacou, but the taxonomic identity and diversity of the Grenada Bank rice rats has remained uncertain. We provide a morphology-based description of rice rats from Grenada and Carriacou, and analyze their phylogenetic and biogeographical affinities to other Caribbean and mainland Neotropical oryzomyines. We recognize two taxa from the Grenada Bank: we describe the new species Megalomys camerhogne from Pearls (Grenada), representing the largest-bodied member of the extinct endemic Caribbean genus Megalomys, and we refer smaller-bodied oryzomyine material from Pearls and Sabazan (Carriacou) to the widespread extant Neotropical species Zygodontomys brevicauda. Body size variation within Megalomys correlates with island bank area and might thus reflect historical rather than modern biogeography. Zygodontomys specimens from the Grenada Bank fall within the upper end of size variation in extant populations and may constitute an example of 'island gigantism', but it is possible that occurrence of this widespread species on the Grenada Bank might reflect prehistoric human-mediated translocation. We predict further endemic Caribbean rice rat taxa remain to be discovered, including a possible species of Megalomys on the neighbouring island of St. Vincent.

Genomic consequences of human-mediated translocations in margin populations of an endangered amphibian.

Due to their isolated and often fragmented nature, range margin populations are especially vulnerable to rapid environmental change. To maintain genetic diversity and adaptive potential, gene flow from disjunct populations might therefore be crucial to their survival. Translocations are often proposed as a mitigation strategy to increase genetic diversity in threatened populations. However, this also includes the risk of losing locally adapted alleles through genetic swamping. Human‐mediated translocations of southern lineage specimens into northern German populations of the endangered European fire‐bellied toad (Bombina bombina) provide an unexpected experimental set‐up to test the genetic consequences of an intraspecific introgression from central population individuals into populations at the species range margin. Here, we utilize complete mitochondrial genomes and transcriptome nuclear data to reveal the full genetic extent of this translocation and the consequences it may have for these populations. We uncover signs of introgression in four out of the five northern populations investigated, including a number of introgressed alleles ubiquitous in all recipient populations, suggesting a possible adaptive advantage. Introgressed alleles dominate at the MTCH2 locus, associated with obesity/fat tissue in humans, and the DSP locus, essential for the proper development of epidermal skin in amphibians. Furthermore, we found loci where local alleles were retained in the introgressed populations, suggesting their relevance for local adaptation. Finally, comparisons of genetic diversity between introgressed and nonintrogressed northern German populations revealed an increase in genetic diversity in all German individuals belonging to introgressed populations, supporting the idea of a beneficial transfer of genetic variation from Austria into North Germany.

No genetic signature of glacial refugia in current European fallow deer (Dama dama dama L., 1758) populations: a comment on Baker et al. (2017)

Genetic data are crucial for making inferences about the evolutionary history of species and deriving guidelines for conservation strategies. In conservation genetics studies, each step should be critically evaluated, from sampling strategy to data quality assessment and analytical methods: potential issues and biases should be considered, reproducibility should be guaranteed and the results of different analyses should be critically evaluated. By incorporating all these steps, we re-analysed data from Baker et al. (Heredity 119:16–26, 2017): our results led to conclusions that contradict the ones reached by the authors, which were based on weak support and biased analyses. European fallow deer current genetic makeup most likely derives from extensive human-mediated translocations. The genetic expectations of glacial refugia hypothesis cannot be found in current European fallow deer populations.

Alien and cryptogenic Foraminifera in the Mediterranean Sea: A revision of taxa as part of the EU 2020 Marine Strategy Framework Directive

The human-mediated translocation of marine alien species beyond their natural ranges started as early as people began navigating the sea and is of growing concern to nature conservation. The Mediterranean Sea is among the most severely affected areas by biological invasions, a phenomenon that has been fostered by the opening and recent extension of the Suez Canal, the transport and release of ballast water, aquaculture and aquarium trade, ichthyochory and other active or passive dispersal mechanisms. The increase of marine invasions has stimulated considerable research, but for some important groups, in particular microorganisms, data are still limited. In this paper we have reviewed the current status of marine alien foraminifera in the Mediterranean Sea. Our survey includes a comrephensive taxonomic revision of previously recognized alien taxa, and new information obtained from the fossil record and from molecular studies. Our survey and reexamination of alien benthic foraminifera yielded a total of 43 validly recognized species and two species of cryptogenic taxa and reduces the number of previous recordings. The revised list includes both larger symbiont-bearing and smaller benthic foraminifera, including 16 hyaline-perforate, 3 agglutinated and 24 porcelaneous taxa. The vast majority of alien foraminifera recorded so far have become established in the Eastern and Central Mediterranean Sea, indicative for translocation and introduction via the Suez Canal pathway. Only one species, Amphistegina lobifera, causes significant ecological impacts and fulfills the criteria to be considered as an invasive alien. This species is a prolific carbonate producer, and displays extreme forms of ecosystem invasibility with capabilities to reduce native diversity and species richness. The proliferation and rates of recently observed range extensions, track contemporary sea surface temperature increases, provide strong support for previous species distribution models, and corroborate findings that rising water temperatures, global climate change and the extension of climate belts are major drivers fueling the latitudinal range expansion of larger symbiont-bearing and smaller epiphytic foraminifera. Intensified efforts to study alien foraminifera on a molecular level, in dated cores and in ballast water are required to trace their source of origin, to identify vectors of introduction and to verify their status as true aliens.

Biogeographic problem-solving reveals the Late Pleistocene translocation of a short-faced bear to the California Channel Islands

An accurate understanding of biodiversity of the past is critical for contextualizing biodiversity patterns and trends in the present. Emerging techniques are refining our ability to decipher otherwise cryptic human-mediated species translocations across the Quaternary, yet these techniques are often used in isolation, rather than part of an interdisciplinary hypothesis-testing toolkit, limiting their scope and application. Here we illustrate the use of such an integrative approach and report the occurrence of North America’s largest terrestrial mammalian carnivore, the short-faced bear, Arctodus simus, from Daisy Cave (CA-SMI-261), an important early human occupation site on the California Channel Islands. We identified the specimen by corroborating morphological, protein, and mitogenomic lines of evidence, and evaluated the potential natural and anthropogenic mechanisms of its transport and deposition. While representing just a single specimen, our combination of techniques opened a window into the behavior of an enigmatic species, suggesting that A. simus was a wide-ranging scavenger utilizing terrestrial and marine carcasses. This discovery highlights the utility of bridging archaeological and paleontological datasets to disentangle complex biogeographic scenarios and reveal unexpected biodiversity for island systems worldwide.

The future of endangered crayfish in light of protected areas and habitat fragmentation

The long-term survival of a species requires, among other things, gene flow between populations. Approaches for the evaluation of fragmentation in the frame of freshwater habitats consider only a small amount of the information that combined demography and geography are currently able to provide. This study addresses two species of Austropotamobius crayfish in the light of population genetics, spatial ecology and protected areas of the Carpathians. Advancing the classical approaches, we defined ecological distances upon the rasterised river network as a surrogate of habitat resistance to migration, quantifying the deviations from the species´ suitability range for a set of relevant geospatial variables in each cell of the network. Molecular analyses revealed the populations of the two Austropotamobius crayfish species are clearly distinct, lacking hybridisation. Comparing pairs of populations, we found, in some cases, a strong disagreement regarding genetic and ecological distances, potentially due to human-mediated translocations or the geophysical phenomena of regressive erosion, which may have led to unexpected colonisation routes. Protected areas were found to offer appropriate local habitat conditions but failed to ensure connectivity. The methodology applied in this study allowed us to quantify the contribution of each geospatial (environmental) variable to the overall effect of fragmentation, and we found that water quality was the most important variable. A multilevel approach proved to reveal a better understanding of drivers behind the distribution patterns, which can lead to more adequate conservation measures.

Genetic structure and divergence of tench Tinca tinca European populations.

The tench Tinca tinca is a freshwater species with human-mediated translocations, aquaculture interest and limited information on its genetic structure. mtDNA sequencing analysis of control region and two genes in 50 individuals from five European populations identified two phylogroups, with greater variability than that reported until now, and a hybridization zone in the Danube River region. Restriction analyses of additional samples reveal the complicated genetic structure characteristics of tench's wild and translocated populations, supporting future breeding practices.

Genetic divergence and evidence of human-mediated translocation of two-fingered sloths (Choloepus hoffmanni) in Costa Rica.

Sloths are notoriously slow and consequently have limited dispersal ability, which makes them particularly vulnerable to the effects of habitat fragmentation and degradation. Sloths in Costa Rica are considered of conservation concern due to habitat loss, livestock production and increasing urbanization. Reintroductions from rescue centres are commonplace across the country, yet their genetic diversity and population structure are unknown, and there is currently little consideration of the genetic background prior to intervention or releases. We used microsatellite analysis to undertake the first exploratory investigation into sloth population genetics in Costa Rica. Using data from 98 two‐fingered sloths (Choloepus hoffmanni) from four different geographic regions, we determined the presence of four potential genetic groups, three of them with minimal population structuring despite the limited dispersal ability and presence of physical barriers. Sloths from the North appear to represent a highly distinct population that we propose may require management as a discrete unit for conservation. We stress the need for additional analyses to better understand the genetic structure and diversity of North andWest regions and suggest that rescue facilities in Costa Rica should consider the genetic background of rehabilitated sloths when planning future reintroductions. Our results also highlight the threat posed by physical isolation due to widespread urbanization and agriculture expansion for a species with a weak dispersal ability.

Trade and stowaways: molecular evidence for human-mediated translocation of eastern skinks into the western Mediterranean

Abstract Human movements in the regions surrounding the Mediterranean Sea have caused a great impact in the composition of terrestrial fauna due to the introductions of several allochthonous species, intentionally or not. Reptiles are one of the groups where this anthropic impact is most evident, owing to the extensive intra-Mediterranean dispersals of recent chronologies. Chalcides ocellatus is a widespread skink with a natural distribution that covers almost the entire Mediterranean Basin. Two hypotheses have been proposed to explain its origin: natural dispersions and human translocations. Previous molecular data suggest the occurrence of a recent dispersal phenomenon across the Mediterranean Sea. In this study we present the first record of this species in the Iberian Peninsula, in Serra del Molar (South-east Spain). We combined molecular analyses and archaeological records to study the origin of this population. The molecular results indicate that the population is phylogenetically closely related to specimens from north-eastern Egypt and southern Red Sea. We suggest that the species arrived at the Iberian Peninsula most likely through human-mediated dispersal by using the trade routes. Between the Iron to Middle Ages, even now, the region surrounding Serra del Molar has been the destination of human groups and commercial goods of Egyptian origins, in which Chalcides ocellatus could have arrived as stowaways. The regional geomorphological evolution would have restricted its expansion out of Serra del Molar. These findings provide new data about the impact of human movements on faunal introductions and present new information relating to mechanisms of long-distance translocations.