Genetic differentiation in Eurasian Woodcock (Scolopax rusticola) from the Azores

The Eurasian Woodcock Scolopax rusticola is a widespread Palaearctic migratory wader, with purportedly sedentary populations occurring in the Macaronesian archipelago of the Azores. Here we used microsatellite markers to investigate patterns of genetic diversity and differentiation in these insular birds, and compared Azorean populations with those from mainland Europe. Azorean populations show a (non-significant) trend for reduced diversity, and low but consistent differentiation from mainland populations; evidence for widespread over-water migration (in either direction) is weak but must occasionally occur given the recovery of an Azorean ringed bird in France. It is thus likely that the Azorean populations diverged recently from their mainland counterparts, but gene flow is currently restricted.     

Mixed patterns of morphological adaptation to insularity in an aerial displaying bird,the Common Snipe Gallinago gallinago

On islands, colonizing birds may evolve behavioural and morphological adaptations to the new environment, often resulting in changes in body size and reduction or even total loss of flight. These island populations have therefore been used to test hypotheses related to adaptations for flight. However, in certain species in which flight is used not only in foraging and migration but also in mating displays, disentangling the effects of natural and social selection is difficult. Thus, sedentary populations of species that perform aerial displays (such as the Common Snipe Gallinago gallinago that breed in the Azores archipelago) may offer an opportunity to separate the effects of natural and social selection on morphology. If insular Common Snipe respond to the characteristic ecological context of oceanic islands, we expect them to differ from migratory conspecifics in body size and by having relatively smaller and more rounded wings. On the other hand, if social selection exerts a more powerful force over the morphology of this species, we expect that sedentary and migratory birds will not differ in flight‐related characters. We tested these hypotheses by comparing morphological characters measured on live Common Snipe captured in the Azores during the breeding season with those measured on migratory specimens hunted during autumn/winter in mainland Portugal. Sedentary Azorean birds were smaller and had relatively shorter tails but did not show the tendency for insular birds to possess more rounded wings as described in other taxa, including in the Azores. Bergman's rule might explain the difference in body size and shorter tails may be responsible for behavioural differences between populations. The lack of difference in wing shape might be explained by the need of the Common Snipe to perform aerial displays during courtship, suggesting an effect of social selection on the migratory strategy of this species.     

Arthropods (Acarina, Coleoptera, Siphonaptera) in nests of hoopoe (Upupa epops) in Central Europe

In 1993–1995 and 2009–2011, during investigation of reproduction biology of hoopoe, 63 nests of this species were collected after fledging of the chicks in Slovakia and Austria and their arthropod fauna was analyzed. Altogether 5,481 individuals and 34 species of mesostigmatic mites were found in 82.5% of the nests examined. The nidicolous mite Androlaelaps casalis was most abundant and frequent, representing 91.7% of all individuals. The richest in species were saprophilous mites (64.7% of all recorded species), while ectoparasites of the genera Dermanyssus and Ornithonyssus represented only 0.4% of all mites. Only 8 beetle species represented by 65 individuals were found in 18 nests. The dominant trophical group were carnivores (mainly nidicolous Gnathoncus buyssoni) with almost identical representation in (86.2%), followed by a similar representation of necrophags (10.8%). Unlike nests of other birds, the typical nidicolous species Haploglossa puncticollis and the fungivors were absent due to the dry character of studied countryside and placement of the nests in boxes situated in vineyard cottages. Only one species of fleas, Ceratophyllus gallinae — parasitizing first of all in the passeriform birds and being particularly abundant in the cavity nesting birds was recorded in hoopoe nests.     

Genetic structure of house mouse (Mus musculus Linnaeus 1758) populations in the Atlantic archipelago of the Azores: colonization and dispersal

We analyzed the genetic structure and relationships of house mouse (Mus musculus) populations in the remote Atlantic archipelago of the Azores using nuclear sequences and microsatellites. We typed Btk and Zfy2 to confirm that the subspecies Mus musculus domesticus was the predominant genome in the archipelago. Nineteen microsatellite loci (one per autosome) were typed in a total of 380 individuals from all nine Azorean islands, the neighbouring Madeiran archipelago (Madeira and Porto Santo islands), and mainland Portugal. Levels of heterozygosity were high on the islands, arguing against population bottlenecking. The Azorean house mouse populations were differentiated from the Portuguese and Madeiran populations and no evidence of recent migration between the three was obtained. Within the Azores, the Eastern, Western, and Central island groups tended to act as separate genetic units for house mice, with some exceptions. In particular, there was evidence of recent migration events among islands of the Central island group, whose populations were relatively undifferentiated. Santa Maria had genetically distinctive mice, which may relate to its colonization history. © 2013 The Linnean Society of London     

Genetic structure in insular and mainland populations of house sparrows (Passer domesticus) and their hemosporidian parasites

Small and isolated populations usually exhibit low levels of genetic variability, and thus, they are expected to have a lower capacity to adapt to changes in environmental conditions, such as exposure to pathogens and parasites. Comparing the genetic variability of selectively neutral versus functional loci allows one to assess the evolutionary history of populations and their future evolutionary potential. The genes of the major histocompatibility complex (MHC) control immune recognition of parasites, and their unusually high diversity is genes which is likely driven by parasite‐mediated balancing selection. Here, we examined diversity and differentiation of neutral microsatellite loci and functional MHC class I genes in house sparrows (Passer domesticus), living in six insular and six mainland populations, and we aimed to determine whether their diversity or differentiation correlates with the diversity and the prevalence of infection of hemosporidian parasites. We found that island bird populations tended to have lower neutral genetic variability, whereas MHC variability gene was similar between island and mainland populations. Similarly, island populations tended to show greater genetic differentiation than mainland populations, especially at microsatellite markers. The maintenance of MHC genetic diversity and its less marked structure in the island populations could be attributed to balancing‐selection. The greater MHC differentiation among populations was negatively correlated with similarity in blood parasites (prevalence and diversity of parasite strains) between populations. Even at low prevalence and small geographical scale, haemosporidian parasites might contribute to structure the variability of immune genes among populations of hosts.     

Ecomorphological patterns in the Blackcap Sylvia atricapilla: insular versus mainland populations

Capsule Blackcap Sylvia atricapilla populations from the Azores archipelago show morphological differences to continental birds which are consistent with the ‘Island Rule’.

Aims The morphology of insular vertebrates is usually the result of the evolution in their particular environment and leads to predictable morphological patterns, according to the Island Rule. We test the predictions of the Island Rule, using the Blackcap of the Azores archipelago as our model.

Methods We compared morphological variation (body size and wing shape) of populations from the nine islands of the Azores to continental birds, using multivariate indexes. Also, we looked at the relationship between these patterns and possible insular ecological drivers of morphological divergence.

Results Our findings are concordant with Island Rule predictions, as in general birds from the Azores are larger than continental populations, especially birds from the most distant islands. Wing shape also differs significantly, as Azorean Blackcaps tend to have rounder wings than continental birds with a migratory-like phenotype.

Conclusion Overall, we conclude that the observed morphological patterns in Blackcap in the Azores conform in general to the Island Rule predictions.     

Ectoparasites of northern fulmars Fulmarus glacialis (Procellariiformes: Procellariidae) from the Canadian Arctic

We studied the prevalence and intensity of infestation of ectoparasites on northern fulmars (Fulmarus glacialis L.) from a breeding colony in Arctic Canada in June–August 2003. No fleas or ticks were found on any fulmars, but three species of chewing lice (Phthiraptera) were recorded: Ischnocera: Perineus nigrolimbatus (Giebel 1874), Ischnocera: Saemundssonia occidentalis (Kellogg 1896), and Amblycera: Ancistrona vagelli (Fabricius 1787). Non-breeding birds had a higher prevalence of lice than breeding birds, and prevalence varied markedly among louse species. Our study is an important baseline for the occurrence of ectoparasites on northern fulmars in the high Arctic, a region undergoing extensive environmental change due to global warming, and an area where parasites are expected to extend ranges or increase in prevalence under changing annual temperature regimes.     

Phylogeography and molecular phylogeny of Macaronesian island Tarphius (Coleoptera: Zopheridae): why are there so few species in the Azores?

Aim We used a phylogenetic framework to examine island colonization and predictions pertaining to differentiation within Macaronesian Tarphius (Insecta, Coleoptera, Zopheridae), and explain the paucity of endemics in the Azores compared with other Macaronesian archipelagos. Specifically, we test whether low diversity in the Azores could be due to recent colonization (phylogenetic lineage youth), cryptic speciation (distinct phylogenetic entities within species) or the young geological age of the archipelago. Location Macaronesian archipelagos (Azores, Madeira and the Canary Islands), northern Portugal and Morocco. Methods Phylogenetic analyses of mitochondrial and nuclear genes of Tarphius beetles of the Azores, other Macaronesian islands and neighbouring continental areas were used to investigate the origin of island biodiversity and to compare patterns of colonization and differentiation. A comparative nucleotide substitution rate test was used to select the appropriate substitution rate to infer clade divergence times. Results Madeiran and Canarian Tarphius species were found to be more closely related to each other, while Azorean taxa grouped separately. Azorean taxa showed concordance between species and phylogenetic clades, except for species that occur on multiple islands, which segregated by island of origin. Divergence time estimates revealed that Azorean Tarphius are an old group and that the most recent intra‐island speciation event on Santa Maria, the oldest island, occurred between 3.7 and 6.1 Ma. Main conclusions Our phylogenetic approach provides new evidence to understand the impoverishment of Azorean endemics: (1) Tarphius have had a long evolutionary history within the Azores, which does not support the hypothesis of fewer radiation events due to recent colonization; (2) the current taxonomy of Azorean Tarphius does not reflect common ancestry and cryptic speciation is responsible for the underestimation of endemics; (3) intra‐island differentiation in the Azores was found only in the oldest island, supporting the idea that young geological age of the archipelago limits the number of endemics; and (4) the lack of evidence for recent intra‐island diversification in Santa Maria could also explain the paucity of Azorean endemics. Phylogenetic reconstructions of other species‐rich taxa that occur on multiple Macaronesian archipelagos will reveal whether our conclusions are taxon specific, or of a more general nature.     

Factores asociados con la presencia de endoparásitos y ectoparásitos en perros domiciliados de la zona metropolitana de Toluca,México

Introduction:

Endoparasites and ectoparasites in dogs are of global distribution. The close relationship between dogs and man implies a risk for the transmission of zoonotic parasites. Therefore, it is necessary to determine the parasites hosted by dogs in specific areas and the factors associated with their presence.

Objectives:

To identify and to estimate the prevalence of endoparasites and ectoparasites in domiciled dogs in the Metropolitan area of Toluca, México, and the prevalence of D. caninum in fleas of the genus Ctenocephalides spp.

Materials and methods:

We collected samples from 402 domiciled dogs in four reference hospitals in the area in Toluca. We diagnosed endoparasites using direct smear, flotation, and sedimentation techniques and we performed the taxonomic identification of ectoparasites. Finally, the molecular diagnosis of D. caninum in fleas was made using the polymerase chain reaction technique (PCR).

Results:

A total of 37.2% of dogs were positive for endoparasites; the genera or species identified were Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp., and Trichuris vulpis; the prevalence of ectoparasites was 13.13%. We identified fleas of the species Ctenocephalides felis, Ctenocephalides canis; only one animal was parasitized with Rhipicephalus sanguineus and another one with Trichodectes canis; the prevalence of D. caninum in fleas was 9.5%.

Conclusion:

The prevalence of endoparasites was 37.2% while that of ectoparasites was 13.1%; this is the first analysis of endoparasites and ectoparasites conducted in the same population of dogs in México together with the molecular diagnosis of D. caninum in fleas.     

Population genetic structure and conservation of the Azorean tree Prunus azorica (Rosaceae)

Prunus azorica is an endangered tree endemic to the Azores Archipelago, considered as a top priority species for conservation. Although propagation measures have been studied in detail, and a broad phylogeographic study on P. lusitanica was recently published, a detailed population genetics study devoted to Azorean taxon was lacking. To determine extant patterns of population genetic structure in P. azorica, we analysed eight populations from the five Azorean islands where the species presently occurs and the only extant individual from Flores Island. We also included samples of P. lusitanica subsp. hixa from the Canary Islands and Madeira, and of P. lusitanica subsp. lusitanica from mainland Portugal. Genotyping was undertaken for eight nuclear microsatellite polymorphic loci specifically isolated for P. azorica. Accessions of the different geographic regions were used to sequence ITS and trnL DNA regions. Regarding SSRs, the number of alleles ranged from 5 to 37 (mean = 12.6) per locus and from 2 to 64 per population (mean = 24). Our analysis showed a clear separation between samples from the Azores and those from other regions. Overall, São Miguel populations seemed to encompass the majority of the variability found within the archipelago. Regarding the Azorean populations only, the highest percentage of genetic variation was found within populations (92 %). Still, about 7 % of the variation was found among populations within islands. Expected heterozygosity ranged from values near 0 in the most depauperate populations up to 0.18. With a few exceptions, the level of differentiation between Azorean populations was generally low and gene flow was clearly above 1. Analysis of ITS sequences also detected differences between the Azores and the remaining regions but the trnL region did not reveal any variation. The genetic identity of P. azorica was recognised and thus should be preserved; however, the present results suggest that the Azorean taxon should be reinstated at the subspecies level.     

Searching for generality in the patterns of parasite abundance and distribution: Ectoparasites of a South African rodent, Rhabdomys pumilio

We studied abundance and distribution of seven ectoparasite species (fleas Chiastopsylla rossi and Dynopsyllus ellobius, a louse Polyplax arvicanthis, mites Androlaelaps fahrenholzi and Laelaps giganteus and two ticks Haemaphysalis elliptica and Hyalomma truncatum) exploiting the same populations of the rodent host Rhabdomys pumilio in South Africa. We considered three general patterns of abundance and distribution, namely (i) aggregated distribution of parasites amongst individual hosts; (ii) positive relationships between mean parasite abundance and their prevalence; and (iii) applicability of a simple epidemiological model based on mean parasite abundance and its variance to predict the observed patterns of prevalence. Our aims were to evaluate the relative role of host- versus parasite-associated factors by looking at similarity amongst different parasites in these patterns. In general, all parasites demonstrated strong similarity in each of the three patterns of abundance and distribution. However, the strength of these patterns differed amongst parasite species. We conclude that these patterns are driven mainly by hosts, but differences are caused by differences between various life-history traits of parasite species. Our results support the idea that general laws apply to parasite population ecology.     

Peopling of the Azores Islands (Portugal): data from the Y chromosome

Nine Atlantic islands with approximately five and a half centuries of demographic history constitute the Portuguese archipelago of the Azores. Despite the recent peopling history of these islands, written records regarding the specific origin and relative proportions of the first settlers are scarce and incomplete. To gain insights into the history of the peopling of the Azores and to evaluate to what extent population imports described in historical sources left their marks on the genetic constitution of the present-day populations, we analyzed 11 Y-chromosome biallelic markers in a sample of 145 unrelated individuals of Azorean ancestry. The main results of this study indicate that the genetic profile of the Azorean male population shows high affinities with that of mainland Portugal, in accordance with the general knowledge, derived from historical sources, that the Portuguese were the major contributors to the Azorean founding population. Nevertheless, genetic traces of settlers from other origins also mentioned in historical records can still be found in the present-day population. Thus typically sub-Saharan male lineages were detected in the archipelago, in contrast to what has been described for mainland Portugal. Furthermore, compared to what has been described for the mainland Portugal population, our data support a stronger influence of people of Jewish origin, as detected by an increased frequency of lineages belonging to haplogroup J.     

Out-of-Africa,human-mediated dispersal of the common cat flea,Ctenocephalides felis: The hitchhiker’s guide to world domination

The cat flea (Ctenocephalides felis) is the most common parasite of domestic cats and dogs worldwide. Due to the morphological ambiguity of C. felis and a lack of — particularly largescale — phylogenetic data, we do not know whether global C. felis populations are morphologically and genetically conserved, or whether human-mediated migration of domestic cats and dogs has resulted in homogenous global populations. To determine the ancestral origin of the species and to understand the level of global pervasion of the cat flea and related taxa, our study aimed to document the distribution and phylogenetic relationships of Ctenocephalides fleas found on cats and dogs worldwide. We investigated the potential drivers behind the establishment of regional cat flea populations using a global collection of fleas from cats and dogs across six continents. We morphologically and molecularly evaluated six out of the 14 known taxa comprising genus Ctenocephalides, including the four original C. felis subspecies (Ctenocephalides felis felis, Ctenocephalides felis strongylus, Ctenocephalides felis orientis and Ctenocephalides felis damarensis), the cosmopolitan species Ctenocephalides canis and the African species Ctenocephalides connatus. We confirm the ubiquity of the cat flea, representing 85% of all fleas collected (4357/5123). Using a multigene approach combining two mitochondrial (cox1 and cox2) and two nuclear (Histone H3 and EF-1α) gene markers, as well as a cox1 survey of 516 fleas across 56 countries, we demonstrate out-of-Africa origins for the genus Ctenocephalides and high levels of genetic diversity within C. felis. We define four bioclimatically limited C. felis clusters (Temperate, Tropical I, Tropical II and African) using maximum entropy modelling. This study defines the global distribution, African origin and phylogenetic relationships of global Ctenocephalides fleas, whilst resolving the taxonomy of the C. felis subspecies and related taxa. We show that humans have inadvertently precipitated the expansion of C. felis throughout the world, promoting diverse population structure and bioclimatic plasticity. By demonstrating the link between the global cat flea communities and their affinity for specific bioclimatic niches, we reveal the drivers behind the establishment and success of the cat flea as a global parasite.     

Mitochondrial DNA variation and population structure of the island endemic Azorean bat (Nyctalus azoreum)

The Azorean bat Nyctalus azoreum is the only endemic mammal native to the remote archipelago of the Azores. It evolved from a continental ancestor related to the Leisler's bat Nyctalus leisleri and is considered threatened because of its restricted and highly fragmented distribution. We studied the genetic variability in 159 individuals from 14 colonies sampled throughout the archipelago. Sequences of the D-loop region revealed moderate but highly structured genetic variability. Half of the 15 distinct haplotypes were restricted to a single island, but the most common was found throughout the archipelago, suggesting a single colonization event followed by limited interisland female gene flow. All N. azoreum haplotypes were closely related and formed a star-like structure typical of expanded populations. The inferred age of demographic expansions was consistent with the arrival of founder animals during the Holocene, well before the first humans inhabited the Azores. Comparisons with a population of N. leisleri from continental Portugal confirmed not only that all N. azoreum lineages were unique to the archipelago, but also that the current levels of genetic diversity were surprisingly high for an insular species. Our data imply that the Azorean bat has a high conservation value. We argue that geographical patterns of genetic structuring indicate the existence of two management units.     

Prevalence of Fleas and Gastrointestinal Parasites in Free-Roaming Cats in Central Mexico

The prevalence of fleas and gastrointestinal parasites in free-roaming and domestic cats in central Mexico was evaluated. Three hundred and fifty eight cats captured in the street or brought in by owners to the Animal Control Center Unit, a unit of State Government, from June 2010 to May 2011, were included in the study. All cats were examined for the presence of fleas and gastrointestinal worms. One-hundred and ninety (53%) cats were infested with at least one flea species. Single infestations were observed in 106 (30%) cats and mixed infestations in 84 (23%) cats. Four species of fleas were recovered: Ctenocephalides felis in 53% of the cats, C. canis in 18%, Echidnophaga gallinacea in 7% and Pulex irritans in 1%. One-hundred and sixty three (45%) cats were infected with one or more species of gastrointestinal parasites: 48 (13%) with nematodes, 145 (40%) with cestodes, and one animal presented Moniliformis moniliformis. Prevalences and mean intensity of infection were: Physaloptera praeputialis 7 and 18; T. cati 3 and 2; Ancylostoma tubaeforme 2.5 and 2; Toxascaris leonina 0.5 and 2; Dipylidium caninum 36 and 32; Taenia taeniformis 4 and 3 and Moniliformis moniliformis 0.3 and 106, respectively. There was significant association (P<0.01), between season and ectoparasites load, more fleas were obtained in the summer and autumn than in the winter and spring; however, no statistical difference was observed for endoparasites load (P>0.05). The correlation between the total number of ectoparasites and endoparasites was not significant (r = 0.089, P = 0.094).     

Ectoparasites of terrestrial vertebrates inhabiting the Georgia Barrier Islands, USA: an inventory and preliminary biogeographical analysis

Aim To document ectoparasitic arthropods of terrestrial vertebrates inhabiting barrier islands and to offer preliminary interpretations. Location The coast of Georgia, USA, with most data presented for St Catherines, Sapelo, Jekyll, and Cumberland islands. Methods Ectoparasites were collected and identified from hundreds of live‐trapped mammals, birds, and reptiles. Ticks and louse‐flies were also collected by dragging or flagging a white cloth through vegetation. Some ectoparasites were recovered from host nests or roosting sites. Literature records and specimen records from the US National Tick Collection supplemented these data. Results Inventories of ectoparasite species recovered from vertebrates on each island are provided. Many new records and a small number of undescribed species are reported. Main conclusions Compared with most ectoparasite faunas associated with the same host species on the adjacent mainland, ectoparasite species diversity on the barrier islands is depauperate. Possible reasons for this phenomenon are discussed including ecological, geological, and vicariant factors. Tick faunas do not appear to be depauperate on the islands probably because immature stages attach to visiting or migrating birds. Some host‐ectoparasite associations that we recorded are atypical for mainland faunas. This trend has also been recorded in some previous surveys of insular ectoparasites and may be related to vacant ectoparasite niches on some islands.     

Of fleas and geese: the impact of an increasing nest ectoparasite on reproductive success

Past studies on the relationship between nest ectoparasites and avian fitness have been primarily limited to altricial hosts. Life history strategies of precocial and altricial birds vary considerably, limiting our ability to infer the effect of nest parasites on fitness of precocial species. Ross's Chen rossii and lesser snow goose Chen caerulescens caerulescens populations have been growing at unprecedented high rates. New limiting factors on vital rates of these precocial birds may arise after populations have been released from previously regulating factors. The flea Ceratophyllus vagabundus vagabundus is an apparently newly emerging nest parasite in the arctic goose colony at Karrak Lake, Nunavut, Canada. We examined the relationship between flea abundance (measured by the proportion of goose eggs covered by blood in each nest) and goose reproductive success from 2001–2004. In three of four years of study, nest success was inversely related to flea abundance in nests. Despite the potential for high costs to individuals, the overall effects of fleas on goose nesting success have thus far been small. We demonstrated that nest parasites negatively influence reproductive success of precocial bird hosts despite host life history strategy of leaving the nest quickly after hatch, which results in minimal exposure to nest parasites compared to altricial birds that raise their young in the nest.     

Selection underlies phenotypic divergence in the insular Azores woodpigeon

The study of phenotypic evolution in island birds following colonization is a classic topic in island biogeography. However, few studies explicitly test for the role of selection in shaping trait evolution in these taxa. Here, we studied the Azores woodpigeon (Columba palumbus azorica) to investigate differences between island and mainland populations, between females and males, and interactions between geographical origin and sex, by using spectrophotometry to quantify plumage colour and linear measurements to examine external and skeletal morphology. We further tested if selection explains the observed patterns by comparing phenotypic differentiation to genome‐wide neutral differentiation. Our findings are consistent with several predictions of morphological evolution in island birds, namely differences in bill, flight and leg morphology and coloration differences between island and mainland birds. Interestingly, some plumage and morphological traits that differ between females and males respond differently according to geographical origin. Sexual dimorphism in colour saturation is more pronounced in the mainland, but this is driven by selection on female plumage coloration. Differences in flight morphology between females and males are also more pronounced in the mainland, possibly to accommodate contrasting pressures between migration and flight displays. Overall, our results suggest that phenotypic differentiation between mainland and island populations leading to divergent sexual dimorphism patterns can arise from selection acting on both females and males on traits that are likely under the influence of natural and sexual selection.     

Immunological change in a parasite-impoverished environment: divergent signals from four island taxa

Dramatic declines of native Hawaiian avifauna due to the human-mediated emergence of avian malaria and pox prompted an examination of whether island taxa share a common altered immunological signature, potentially driven by reduced genetic diversity and reduced exposure to parasites. We tested this hypothesis by characterizing parasite prevalence, genetic diversity and three measures of immune response in two recently-introduced species (Neochmia temporalis and Zosterops lateralis) and two island endemics (Acrocephalus aequinoctialis and A. rimitarae) and then comparing the results to those observed in closely-related mainland counterparts. The prevalence of blood parasites was significantly lower in 3 of 4 island taxa, due in part to the absence of certain parasite lineages represented in mainland populations. Indices of genetic diversity were unchanged in the island population of N. temporalis; however, allelic richness was significantly lower in the island population of Z. lateralis while both allelic richness and heterozygosity were significantly reduced in the two island-endemic species examined. Although parasite prevalence and genetic diversity generally conformed to expectations for an island system, we did not find evidence for a pattern of uniformly altered immune responses in island taxa, even amongst endemic taxa with the longest residence times. The island population of Z. lateralis exhibited a significantly reduced inflammatory cell-mediated response while levels of natural antibodies remained unchanged for this and the other recently introduced island taxon. In contrast, the island endemic A. rimitarae exhibited a significantly increased inflammatory response as well as higher levels of natural antibodies and complement. These measures were unchanged or lower in A. aequinoctialis. We suggest that small differences in the pathogenic landscape and the stochastic history of mutation and genetic drift are likely to be important in shaping the unique immunological profiles of small isolated populations. Consequently, predicting the impact of introduced disease on the many other endemic faunas of the remote Pacific will remain a challenge.     

Symbiotic flagellate protists as cryptic drivers of adaptation and invasiveness of the subterranean termite Reticulitermes grassei Clément

Changes in flagellate protist communities of subterranean termite Reticulitermes grassei across different locations were evaluated following four predictions: (i) Rural endemic (Portugal mainland) termite populations will exhibit high diversity of symbionts; (ii) invasive urban populations (Horta city, Faial island, Azores), on the contrary, will exhibit lower diversity of symbionts, showing high similarity of symbiont assemblages through environmental filtering; (iii) recent historical colonization of isolated regions—as the case of islands—will imply a loss of symbiont diversity; and (iv) island isolation will trigger a change in colony breeding structure toward a less aggressive behavior. Symbiont flagellate protist communities were morphologically identified, and species richness and relative abundances, as well as biodiversity indices, were used to compare symbiotic communities in colonies from urban and rural environments and between island invasive and mainland endemic populations. To evaluate prediction on the impact of isolation (iv), aggression tests were performed among termites comprising island invasive and mainland endemic populations. A core group of flagellates and secondary facultative symbionts was identified. Termites from rural environments showed, in the majority of observed colonies, more diverse and abundant protist communities, probably confirming prediction (i). Corroborating prediction (ii), the two least diverse communities belong to termites captured inside urban areas. The Azorean invasive termite colonies had more diverse protist communities than expected and prediction (iii) which was not verified within this study. Termites from mainland populations showed a high level of aggressiveness between neighboring colonies, in contrast to the invasive colonies from Horta city, which were not aggressive to neighbors according to prediction (iv). The symbiotic flagellate community of R. grassei showed the ability to change in a way that might be consistent with adaptation to available conditions, possibly contributing to optimization of the colonization of new habitats and spreading of its distribution area, highlighting R. grassei potential as an invasive species.