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Invasive species are one of the greatest threats to biodiversity, with endemic species on islands being at particular risk. Management programs can help to minimize these impacts, but such programs are most successful when they are well-informed. In the Galapagos Islands, Ecuador, a recently introduced avian parasitic fly, Philornis downsi, has had strong negative effects on the survival of multiple endemic bird species, including several species of Darwin’s finches. The fly now populates most of the major islands within the Archipelago and the need to better understand the population structure and connectivity patterns of this invasive fly has become increasingly apparent as various management efforts are being considered. Here, we use genomic and phylogenetic approaches to estimate population structure and connectivity for P. downsi collected from five islands within the Galapagos Islands and several sites in mainland Ecuador, which is the presumptive origin of the invasive population. Genomic data showed very little genetic differentiation between island populations of P. downsi relative to the mainland. Phylogenetic analyses, which used more conservative genetic markers than the genomics approach, showed that island and mainland populations of flies were highly related. Our study provides some of the first results using genetic data to quantify differentiation among mainland and island populations of P. downsi. In addition, our study found very little genetic differentiation between island populations of flies, suggesting that there may be considerable gene flow among islands; however, further sampling is needed to determine the extent to which this could be occurring. As management techniques aimed at controlling the impact of this parasite on endemic bird populations are being considered, our study provides important insights into the history of P. downsi’s invasion to the Galapagos Islands and current population connectivity patterns.

The yellow paper wasp, Polistes versicolor (Olivier) was first recorded in the Galapagos archipelago in 1988. Its life cycle and ecological impacts were studied on two islands 11 yr after it was first discovered. This invasive wasp adapted quickly and was found in most environments. Colony counts and adult wasp monitoring showed a strong preference for drier habitats. Nest activities were seasonally synchronized, nest building followed the rains in the hot season (typically January–May), when insect prey increases, and peaked as temperature and rains started to decline. Next, the number of adult wasps peaked during the cool season when there is barely any rain in the drier zones. In Galapagos, almost half of the prey loads of P. versicolor were lepidopteran larvae, but wasps also carried spiders, beetles, and flies back to the colonies. An estimated average of 329 mg of fresh insect prey was consumed per day for an average colony of 120–150 wasp larvae. The wasps preyed upon native and introduced insects, but likely also affect insectivorous vertebrates as competitors for food. Wasps may also compete with native pollinators as they regularly visited flowers to collect nectar, and have been recorded visiting at least 93 plant species in Galapagos, including 66 endemic and native plants. Colonies were attacked by a predatory moth, Taygete sphecophila (Meyrick) (Lepidoptera: Autostichidae), but colony development was not arrested. High wasp numbers also affect the activities of residents and tourists. A management program for this invasive species in the archipelago is essential.

The German wasp (Vespula germanica) is a highly successful invader on a global scale. These wasps were first observed in the Western Cape region in South Africa in 1972, and they have the potential to expand their range and cause significant damage to the native biodiversity. Our study used nuclear (DNA microsatellites) and mitochondrial DNA (mtDNA) from 42 wasp colonies to analyse the population genetics of V. germanica in their invaded South African range. We sequenced three mitochondrial genes; cytochrome c oxidase I, cytochrome b and cytochrome c oxidase II. We found six mtDNA haplotypes present in South Africa. Although only a single fertilized queen is sufficient for the establishment of a wasp nest, the probability of a single introduced queen to successfully establish a nest and a population is very small. If multiple queens were introduced at the same time, the probability for more than one haplotype being transferred to the new population increases. Therefore, the true number of queen introductions occurred in South Africa can be inferred to be between two and six. We examined nine microsatellite loci and found weak-to-no genetic sub-structuring, likely due to high dispersal rates. We concluded that German wasps in South Africa maintain a homogenous population with movement of individuals between localities.

Wasps of the genus Vespula are social insects that have become major pests and predators in their introduced range. Viruses present in these wasps have been studied in the context of spillover from honey bees, yet we lack an understanding of the endogenous virome of wasps as potential reservoirs of novel emerging infectious diseases. We describe the characterization of 68 novel and nine previously identified virus sequences found in transcriptomes of Vespula vulgaris in colonies sampled from their native range (Belgium) and an invasive range (New Zealand). Many viruses present in the samples were from the Picorna-like virus family (38%). We identified one Luteo-like virus, Vespula vulgaris Luteo-like virus 1, present in the three life stages examined in all colonies from both locations, suggesting this virus is a highly prevalent and persistent infection in wasp colonies. Additionally, we identified a novel Iflavirus with similarity to a recently identified Moku virus, a known wasp and honey bee pathogen. Experimental infection of honey bees with this novel Vespula vulgaris Moku-like virus resulted in an active infection. The high viral diversity present in these invasive wasps is a likely indication that their polyphagous diet is a rich source of viral infections., publishedVersion

�� 2019, International Union for the Study of Social Insects (IUSSI). Introduced social wasps (Vespula spp.) are a pest in many parts of the world. Recently, a mite species (Pneumolaelaps niutirani) was described and associated with disease symptoms in wasps. The mite does not appear to directly parasitise the wasps, but has been observed in high abundance, feeding on exudates from the mouths of larvae. We investigated the viral and fungal pathogens community in these mites and wasps. We found known viruses including Moku virus in both wasps and mites. Moku virus replicated in mites, likely indicating parasitism. Deformed wing virus, commonly found in wasps, was also detected in mite samples. Furthermore, the presence of putative viral transcripts related to 38 distinct viruses, including seven viruses previously isolated from arthropods, indicated that there may be many more viruses associated with the mite that are potentially shared with Vespula wasps. We also found generalist entomopathogenic fungus Aspergillus to infect both mites and wasps. Twelve distinct Aspergillus species were observed, all of which were found in wasp larvae from nests displaying symptoms of disease, with only one species in larvae from apparently healthy nests. Aspergillus novofumigatus was the most common of these species observed in wasps. Six Aspergillus species, including A. novofumigatus were detected in mites. Aspergillus loads were significantly higher in larvae from diseased nests. Our exploratory study indicates that mites can harbour both viruses and fungi that infect wasps, providing avenues of research into biological control using mites as infection vectors.

CRISPR gene drives have potential for widespread and cost-efficient pest control, but are highly controversial. We examined a potential gene drive targeting spermatogenesis to control the invasive common wasp (Vespula vulgaris) in New Zealand. Vespula wasps are haplodiploid. Their life cycle makes gene drive production challenging, as nests are initiated by single fertilized queens in spring followed by several cohorts of sterile female workers and the production of reproductives in autumn. We show that different spermatogenesis genes have different levels of variation between introduced and native ranges, enabling a potential ‘precision drive’ that could target the reduced genetic diversity and genotypes within the invaded range. In vitro testing showed guide-RNA target specificity and efficacy that was dependent on the gene target within Vespula, but no cross-reactivity in other Hymenoptera. Mathematical modelling incorporating the genetic and life history traits of Vespula wasps identified characteristics for a male sterility drive to achieve population control. There was a trade-off between drive infiltration and impact: a drive causing complete male sterility would not spread, while partial sterility could be effective in limiting population size if the homing rate is high. Our results indicate that gene drives may offer viable suppression for wasps and other haplodiploid pests.

Invasive species cause severe ecological and economic impacts in their introduced ranges. Vespula wasps, native to Eurasia, are a major threat to New Zealand native ecosystems. Understanding factors that influence the success of wasp invasion is pivotal for the development of control strategies. Here, we compare genetic diversity and structure of Vespula germanica and Vespula vulgaris between regions of their native and introduced ranges using microsatellite markers. Our study found lower diversity and lack of genetic structure for both invasive Vespula species within New Zealand. The significant reduction in allelic richness, gene diversity and effective population size illustrate a major bottleneck in New Zealand V. germanica and V. vulgaris populations. Strong signatures of population structure were found for both Vespula species with two clusters being identified as optimal k, approximately corresponding to the native and the invaded ranges. Our results highlight the fact that the lack of genetic diversity does not impede successful invasions in V. germanica and V. vulgaris and encourage further research into mechanisms that promote the success of invasive social insects. Overall, this study provides insights into the genetics of invasive Vespula wasps that can be useful for the development of efficient management strategies.

Permethrin is increasingly used for parasite control in bird nests, including nests of threatened passerines. We present the first formal evaluation of the effects of continued permethrin exposure on the reproductive success and liver function of a passerine, the zebra finch (Taeniopygia guttata), for two generations. We experimentally treated all nest material with a 1% permethrin solution or a water control and provided the material to breeding finches for nest building. The success of two consecutive clutches produced by the parental generation and one clutch produced by first-generation birds were tracked. Finches in the first generation were able to reproduce and fledge offspring after permethrin exposure, ruling out infertility. Permethrin treatment had no statistically significant effect on the number of eggs laid, number of days from clutch initiation to hatching, egg hatch rate, fledgling mass or nestling sex ratio in either generation. However, treating nest material with permethrin significantly increased the number of hatchlings in the first generation and decreased fledgling success in the second generation. Body mass for hatchlings exposed to permethrin was lower than for control hatchlings in both generations, but only statistically significant for the second generation. For both generations, an interaction between permethrin treatment and age significantly affected nestling growth. Permethrin treatment had no effect on liver function for any generation. Permethrin was detected inside 6 of 21 exposed, non-embryonated eggs (28.5% incidence; range: 693–4781 ng of permethrin per gram of dry egg mass). Overall, results from exposing adults, eggs and nestlings across generations to permethrin-treated nest material suggest negative effects on finch breeding success, but not on liver function. For threatened bird conservation, the judicious application of this insecticide to control parasites in nests can result in lower nestling mortality compared to when no treatment is applied. Thus, permethrin treatment benefits may outweigh its sub-lethal effects.

We studied the population genetics of one population sample of hybrid Mallard x Grey Ducks and their lice in New Zealand. We aimed to document the relationship between ectoparasite load and host phenotype, and test for an association between the mtDNA diversity of the lice and their hosts, which is predicted based on maternal care. We found three feather lice species previously described for these hosts: Anaticola crassicornis (wing louse), Anatoecus dentatus (head louse), and Trinoton querquedulae (body louse). No new or rare lice species were uncovered. Most ducks in our sample were more Mallard-like than Grey Duck-like hybrids for the five colour and plumage traits examined. We confirm that based solely on phenotypic characters it is difficult to distinguish between Mallards, hybrids and Grey Ducks. We detected no association between the number of lice and host phenotype for two of the three louse species (while controlling for bird size). However, the Grey Duck-like hybrids had fewer head lice (A. dentatus) than their Mallard-like counterparts. Only three of the 40 hosts had mtDNA haplotypes that characterise Grey Ducks. We present the first genetic data of Anaticola crassicornis, Anatoecus dentatus and Trinoton querquedulae from New Zealand waterfowl. We found that the lice mtDNA had greater sequence diversity than the homologous gene for the ducks. A mitochondrial phylogeny for A. crassicornis collected from hosts worldwide has been previously published, and we added our novel data to infer evolutionary relationships among worldwide populations of this louse. None of the three lice species showed a close association of parasite and host mtDNA lineage despite lack of paternal care in these duck species. Keywords: Anatidae, Chewing lice, Ectoparasites, Hybrids, mtDNA, New Zealand, Transmission, Waterfowl

The survival of parasites is threatened directly by environmental alteration and indirectly by all the threats acting upon their hosts, facing coextinction. The fate of Darwin's finches and their native ectoparasites in the Galapagos Islands is uncertain because of an introduced avian parasitic fly, Philornis downsi, which could potentially drive them to extinction. We documented all known native ectoparasites of Darwin's finches. Thirteen species have been found: nine feather mites, three feather lice and one nest mite. No ticks or fleas have been recorded from them yet. Management options being considered to control P. downsi include the use of the insecticide permethrin in bird nests which would not only kill the invasive fly larvae but the birds’ native ectoparasites too. Parasites should be targeted for conservation in a manner equal to that of their hosts. We recommend steps to consider if permethrin-treated cotton stations are to be deployed in the Galapagos archipelago to manage P. downsi.

The North American signal crayfish (Pacifastacus leniusculus) has been present in Scotland since at least 1995 and the species is now known to be present in a number of catchments. Once established, few opportunities for containment exist and eradication can often be impossible to achieve. However, in small, isolated water bodies, the application of a non-crayfish-specific biocide has provided the opportunity to remove this species permanently. In July 2011, signal crayfish were discovered in a flooded quarry pond at Ballachulish in the Scottish Highlands. This is an isolated site located ~100 km from the nearest known population and it is likely that the population was established as the result of a deliberate release of these animals 10 years previously. Experience gained from using the eradication technique at other sites in the UK led to the site being treated with a natural pyrethrum biocide (Pyblast®) in June 2012. Post treatment monitoring from 2012–2017 indicates that eradication has been successful. Monitoring of native species affected by the biocide suggests that both invertebrates and amphibians quickly recolonised the quarry pond. Eradication of crayfish using biocide is only feasible in water bodies where the entire population of crayfish can be exposed to a lethal dose and the impact on non-target species can be accepted. The technique is not appropriate for large, connected water bodies, although it may be possible to treat short stretches of canals where biocide exposure can be controlled and isolated populations of crayfish can be effectively treated.

The declining-population paradigm holds that small populations are particularly vulnerable to anthropogenic influences such as habitat destruction, pollution and species introductions. While the effects of particular stressors, such as parasitism, may be unimportant in a large, healthy population, they can be serious and even devastating in situations characterized by a restricted geographic range, or by fragmented or reduced population sizes. We apply this idea to nest parasitism of threatened Neotropical bird species that exist in small populations, focusing on dipteran nest parasites in the genus Philornis. We review the literature on Philornis parasitism exerting negative pressure on bird populations that have become small and isolated due to human actions and present a new case of Philornis parasitism of a threatened hummingbird species. Our aim is to raise awareness about the exacerbating effect that nest parasites can have on small and declining bird populations; especially when biological information is scarce. The five reviewed cases involve two species of Darwin?s Finches in the Galápagos Islands attacked by the invasive P. downsi, two species of hawks on islands in the Caribbean attacked by the native P. pici and P. obscura, and the Yellow Cardinal (Gubernatrix cristata) in southern South America attacked by an unknown Philornis species. We also present new documentation of parasitism of a threatened hummingbird species in mainland Ecuador by an unidentified Philornis species. We recommend more field studies to determine the presence of nest parasites in bird populations worldwide to improve understanding how nest parasites affect bird fitness and population viability and to allow time to act in advance if needed. Parasitism by Philornis may represent a severe mortality factor in most already threatened bird species, putting them at greater risk of extinction. Therefore, parasitism management should be included in all threatened species recovery plans. Fil: Bulgarella, Mariana. Victoria University Of Wellington; Fil: Quiroga, Martin Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina Fil: Heimpel, George E.. University of Minnesota; Estados Unidos

Parasite host range can be influenced by physiological, behavioral, and ecological factors. Combining data sets on host-parasite associations with phylogenetic information of the hosts and the parasites involved can generate evolutionary hypotheses about the selective forces shaping host range. Here, we analyzed associations between the nest-parasitic flies in the genus Philornis and their host birds on Trinidad. Four of ten Philornis species were only reared from one species of bird. Of the parasite species with more than one host bird species, P. falsificus was the least specific and P. deceptivus the most specific attacking only Passeriformes. Philornis flies in Trinidad thus include both specialists and generalists, with varying degrees of specificity within the generalists. We used three quantities to more formally compare the host range of Philornis flies: the number of bird species attacked by each species of Philornis, a phylogenetically informed host specificity index (Poulin and Mouillot's S TD), and a branch length-based S TD. We then assessed the phylogenetic signal of these measures of host range for 29 bird species. None of these measures showed significant phylogenetic signal, suggesting that clades of Philornis did not differ significantly in their ability to exploit hosts. We also calculated two quantities of parasite species load for the birds - the parasite species richness, and a variant of the S TD index based on nodes rather than on taxonomic levels - and assessed the signal of these measures on the bird phylogeny. We did not find significant phylogenetic signal for the parasite species load or the node-based S TD index. Finally, we calculated the parasite associations for all bird pairs using the Jaccard index and regressed these similarity values against the number of nodes in the phylogeny separating bird pairs. This analysis showed that Philornis on Trinidad tend to feed on closely related bird species more often than expected by chance.

Philornis downsi (Dodge and Aitken) is a bird-parasitic muscid fly native to mainland South America that recently invaded the Galapagos Islands where it is parasitizing Darwin's finches and other land birds. This parasite was previously known only from Argentina, Brazil, and Trinidad and Tobago. The first report of P. downsi from mainland Ecuador is provided, supporting the hypothesis that the invasion route of P. downsi from its native range to the Galapagos Islands includes mainland Ecuador. Four different morphologies of pupal exuviae, which belong to different fly species, were uncovered. Dipteran puparia were found in 20% of naturally occurring nests collected in 2013 and in 27% of nests in 2014 at the two sites in western Ecuador. P. downsi accounted for 74% and 40% of the puparia in 2013 and 2014, respectively. Two new bird host species for the genus Philornis were recorded: the streak-headed woodcreeper (Lepidocolaptes souleyetii) and the fasciated wren (Campylorhynchus fasciatus). The le...

Populations of the same species inhabiting distinct localities experience different ecological and climatic pressures that might result in differentiation in traits, particularly those related to temperature. We compared metabolic rate (and its thermal sensitivity), growth rate, and body size among nine high- and low-elevation populations of the Wellington tree weta, Hemideina crassidens, distributed from 9 to 1171 m a.s.l across New Zealand. Our results did not indicate elevational compensation in metabolic rates (metabolic cold adaptation). Cold acclimation decreased metabolic rate compared to warm-acclimated individuals from both high- and low-elevation populations. However, we did find countergradient variation in growth rates, with individuals from high-elevation populations growing faster and to a larger final size than individuals from low-elevation populations. Females grew faster to a larger size than males, although as adults their metabolic rates did not differ significantly. The combined physiological and morphological data suggest that high-elevation individuals grow quickly and achieve larger size while maintaining metabolic rates at levels not significantly different from low-elevation individuals. Thus, morphological differentiation among tree weta populations, in concert with genetic variation, might provide the material required for adaptation to changing conditions.

Social wasps are a major pest in many countries around the world. Pathogens may influence wasp populations and could provide an option for population management via biological control. We investigated the pathology of nests of apparently healthy common wasps, Vespula vulgaris, with nests apparently suffering disease. First, next-generation sequencing and metatranscriptomic analysis were used to examine pathogen presence. The transcriptome of healthy and diseased V. vulgaris showed 27 known microbial phylotypes. Four of these were observed in diseased larvae alone (Aspergillus fumigatus, Moellerella wisconsensis, Moku virus, and the microsporidian Vavraia culicis). Kashmir Bee Virus (KBV) was found to be present in both healthy and diseased larvae. Moellerella wisconsensis is a human pathogen that was potentially misidentified in our wasps by the MEGAN analysis: it is more likely to be the related bacteria Hafnia alvei that is known to infect social insects. The closest identification to the putative pathogen identified as Vavraia culicis was likely to be another microsporidian Nosema vulgaris. PCR and subsequent Sanger sequencing using published or our own designed primers, confirmed the identity of Moellerella sp. (which may be Hafnia alvei), Aspergillus sp., KBV, Moku virus and Nosema. Secondly, we used an infection study by homogenising diseased wasp larvae and feeding them to entire nests of larvae in the laboratory. Three nests transinfected with diseased larvae all died within 19 days. No pathogen that we monitored, however, had a significantly higher prevalence in diseased than in healthy larvae. RT-qPCR analysis indicated that pathogen infections were significantly correlated, such as between KBV and Aspergillus sp. Social wasps clearly suffer from an array of pathogens, which may lead to the collapse of nests and larval death.

Aim Species’ responses to climate change are likely to depend on their ability to overcome abiotic constraints as well as on the suite of species with which they interact. Responses to past climate change leave genetic signatures of range expansions and shifts, allowing inferences to be made about species’ distributions in the past, which can improve our ability to predict the future. We tested a hypothesis of ongoing range shifting associated with climate change and involving interactions of two species inferred to exclude each other via competition. Location New Zealand. Methods The distributions of two tree weta species (Hemideina crassidens and H. thoracica) were mapped using locality records. We inferred the likely modern distribution of each species in the absence of congeneric competitors with the software Maxent. Range interaction between the two species on an elevational gradient was quantified by transect sampling. Patterns of genetic diversity were investigated using mitochondrial DNA, and hypotheses of range shifts were tested with population genetic metrics. Results The realized ranges of H. thoracica and H. crassidens were narrower than their potential ranges, probably due to competitive interactions. Upper and lower elevational limits on Mount Taranaki over 15 years revealed expansion up the mountain for H. thoracica and a matching contraction of the low elevation limits of the range of H. crassidens. The observed nucleotide diversity in H. thoracica was consistent with a species that persisted in northern areas during Pleistocene glacial periods, from where it expanded at warmer times. In contrast, a two-tailed distribution of nucleotide diversity in H. crassidens was as expected for a species that expanded northwards during glacials and southwards during interglacials.

Sheldgeese of the genus Chloephaga are waterfowl (Anatidae) endemic to mainland South America and the Falkland Islands (Malvinas). Continental populations of three species C. picta, C. poliocephala, and C. rubidiceps breed in Patagonia and Tierra del Fuego and migrate northwards to winter in central Argentina and Chile. These continental populations have declined by > 50% in the past 30 years due to direct hunting to control crop damage and by the introduction of the grey fox Dusicyon griseus to their breeding grounds in Tierra del Fuego. The continental population of C. rubidiceps is critically endangered, estimated to be < 1,000 individuals. While no historic population size estimates exist for C. rubidiceps in its wintering grounds, the breeding population in Tierra del Fuego was estimated to number several thousand individuals in the 1950s. In contrast, the C. rubidiceps population in the Falkland Islands (Malvinas) is non-migratory and stable with > 42,000 individuals, as is the Falkland Islands (Malvinas) population of C. picta leucoptera with > 138,000 individuals. Here we use sequence data from the mitochondrial DNA control region to quantify genetic divergence between insular and continental populations of these two species of sheldgeese. Chloephaga rubidiceps and C. picta showed significant intraspecific differentiation of 1.0% and 0.6%, respectively. In both cases, mainland and insular populations were reciprocally monophyletic and did not share mtDNA haplotypes. These results suggest that the insular and continental populations of C. rubidiceps and C. picta are genetically distinct and that female-mediated gene flow is restricted. We recommend a reevaluation of the threat category status of the continental C. rubidiceps population, under IUCN guidelines. It is necessary to implement urgent actions for the conservation of this critically endangered population. Fil: Bulgarella, Mariana. Massey University; Nueva Zelanda Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Di Giacomo, Adrian Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Matus, Ricardo. Centro de Rehabilitación Leñadura; Chile Fil: Blank, Viviana Claudia. Centro de Rehabilitación Leñadura; Chile Fil: Wilson, Robert E.. University of Alaska Fairbanks; Estados Unidos Fil: McCracken, Kevin G.. University of Alaska Fairbanks; Estados Unidos

Aim The Malvinas/Falkland Islands (MFI) constitute the largest archipelago inthe southern Atlantic, and harbour endemic lineages that presumably evolvedafter sea-level rise, associated with glacial periods, isolated ancestral popula-tions. We investigate the role of the MFI in isolating populations from conti-nental counterparts of two highly vagile species: the sheldgeese Chloephagapicta and Chloephaga rubidiceps.Location Patagonia and the Malvinas/Falkland Islands.Methods We sampled C. picta and C. rubidiceps on the continent and MFI.Using a reduced-representation genomic approach, we quantified the geneticdifferentiation between insular and continental populations of both species,and used coalescent-based analyses to model their demography.Results The MFI harbour independently evolving lineages of C. picta andC. rubidiceps, which diverged from their continental counterparts during theMiddle-Late Pleistocene and have since experienced negligible gene flow.Main conclusions The c. 450 km that separate the archipelago from thecontinent are sufficient to isolate populations of these putatively highly vagilespecies. Ancestral lineages may have reached the MFI refugium during glacialcycles. Without conservation measures, the drastic decline of the morphologi-cally, behaviourally and ecologically distinct continental population ofC. rubidiceps,to< 1000 individuals, may lead to the extinction of an indepen-dently evolving taxon. Fil: Kopuchian, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Campagna, Leonardo. Cornell University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Di Giacomo, Adrian Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Wilson, Robert E.. University Of Alaska; Estados Unidos Fil: Bulgarella, Mariana. University of Minnesota; Estados Unidos Fil: Petracci, Pablo. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Grupo de Estudios en Conservación y Manejo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mazar Barnett, Juan. Asociación de Ornitología del Plata; Argentina Fil: Matus, Ricardo. Centro de Rehabilitación de aves Leñadura; Chile Fil: Blank, Olivia. Centro de Rehabilitación de aves Leñadura; Chile Fil: McCracken, Kevin G.. University Of Alaska; Estados Unidos

We examined the genetic structuring of rengarenga (Arthropodium cirratum; Asparagaceae), an endemic New Zealand coastal herb, using nuclear microsatellite markers. This species was brought into cultivation by Māori within the last 700-800 years for its edible roots and was transplanted beyond its natural distribution as part of its cultivation. We found very high levels of genetic structuring in the natural populations (FST = 0.84), indicating low levels of gene flow. Reduced genetic diversity was found in the translocated populations, suggesting a large loss of genetic diversity early in the domestication process. The data indicates that rengarenga was brought into cultivation independently at least three times, with the sources of these introductions located within a narrow area encompassing about 250km of coastline. Hybridization was inferred between A. cirratum and the closely related A. bifurcatum, despite A. birfucatum not occurring in the vicinity.

We studied the phylogenetic relationships of four duck genera endemic to South America: Brazilian teal Amazonetta brasiliensis, spectacled duck Speculanas specularis, crested duck Lophonetta specularioides, and four species of steamer ducks Tachyerespatachonicus, T. leucocephalus, T. pteneres, T. brachypterus. Genetic divergence within and among species was compared using population-level sampling of the mitochondrial DNA (mtDNA) control region, supplemented with three additional mtDNA genes and six independent nuclear loci from one individual of each species and a variety of outgroup taxa. The monophyly of these four morphologically divergent South American genera was strongly supported. Within this clade, Amazonetta and Speculanas were supported as sister species in all analyses, but different gene regions yielded conflicting or ambiguous results for Lophonetta and Tachyeres. This lack of resolution resulted from little informative variation in nuclear loci and high levels of homoplasy in the mtDNA control region. Control region sequences from the four Tachyeres species fell into two distinct clades. In one clade, T. patachonicus and T. leucocephalus share a set of closely related haplotypes (≤0.6% sequence divergence); while no identical haplotypes were shared between species, the control region phylogeny was insufficiently resolved to either support or reject reciprocal monophyly. The second clade, ~1.7% divergent from the first, comprised haplotypes of the Falkland Islands species T. brachypterus and a captive individual of T. pteneres. These distinctive South American ducks likely experienced two bouts of rapid diversification, thus making analysis of their phylogenetic relationships difficult. Incomplete lineage sorting, founder effects, and perhaps introgression likely have contributed to obscuring the relationships among steamer ducks.

Premise of the study: Microsatellite markers were developed for Arthropodium cirratum (Asparagaceae) to study population genetic structure and translocation of this species. These markers were tested for cross-amplification in two other Arthropodium species. Methods and Results: Sixteen microsatellite markers were developed from a genomic library and tested in three populations of A. cirratum. The loci exhibited one to five alleles per locus, with private alleles present in each of the populations. Cross-amplification tests in the two other New Zealand Arthropodium species revealed that many of the loci amplify and demonstrate polymorphism in A. bifurcatum. Conclusions: These markers will be useful for determining genetic structure in A. cirratum and for determining the origins of translocated populations of this species.

Hypoxia is one of the most important factors affecting survival at high altitude, and the major hemoglobin protein is a likely target of selection. We compared population genetic structure in the alphaA and betaA hemoglobin subunits (HBA2 and HBB) of five paired lowland and highland populations of Andean dabbling ducks to unlinked reference loci. In the hemoglobin genes, parallel amino acid replacements were overrepresented in highland lineages, and one to five derived substitutions occurred at external solvent-accessible positions on the alpha and beta subunits, at alpha(1)beta(1) intersubunit contacts, or in close proximity to inositolpentaphosphate (IPP) binding sites. Coalescent analyses incorporating the stochasticity of drift and mutation indicated that hemoglobin alleles were less likely to be transferred between highland and lowland populations than unlinked alleles at five other loci. Amino acid replacements that were overrepresented in the highlands were rarely found within lowland populations, suggesting that alleles segregating at high frequency in the highlands may be maladaptive in the lowlands and vice versa. Most highland populations are probably nonmigratory and locally adapted to the Altiplano, but gene flow for several species may be sufficiently high to retard divergence at unlinked loci. Heterozygosity was elevated in the alphaA or betaA subunits of highland populations exhibiting high gene flow between the southern lowlands and the highlands and in highland species that disperse seasonally downslope to midelevation environments from the central Andean plateau. However, elevated heterozygosity occurred more frequently in the alphaA subunit but not simultaneously in both subunits, suggesting that selection may be more constrained by epistasis in the betaA subunit. Concordant patterns among multiple species with different evolutionary histories and depths of historical divergence and gene flow suggest that the major hemoglobin genes of these five dabbling duck species have evolved adaptively in response to high-altitude hypoxia in the Andes.