Human-mediated dispersal of terrestrial species between Antarctic biogeographic regions: A preliminary risk assessment.

The distribution of terrestrial biodiversity within Antarctica is complex, with 16 distinct biogeographic regions (Antarctic Conservation Biogeographic Regions) currently recognised within the Antarctic continent, Peninsula and Scotia Arc archipelagos of the Antarctic Treaty area. Much of this diversity is endemic not only to Antarctica as a whole, but to specific regions within it. Further complexity is added by inclusion of the biodiversity found on the islands located in the Southern Ocean north of the Treaty area. Within Antarctica, scientific, logistic and tourism activities may inadvertently move organisms over potentially long distances, far beyond natural dispersal ranges. Such translocation can disrupt natural species distribution patterns and biogeography through: (1) movement of spatially restricted indigenous species to other areas of Antarctica; (2) movement of distinct populations of more generally distributed species from one area of Antarctica to another, leading to genetic homogenisation and loss of assumed local patterns of adaptation; and (3) further dispersal of introduced non-native species from one area of Antarctica to another. Species can be moved between regions in association with people and cargo, by ship, aircraft and overland travel. Movement of cargo and personnel by ship between stations located in different biogeographic regions is likely to present one of the greatest risks, particularly as coastal stations may experience similar climatic conditions, making establishment more likely. Recognising that reducing the risk of inter-regional transfer of species is a priority issue for the Antarctic Treaty Consultative Meeting, we make practical recommendations aimed at reducing this risk, including the implementation of appropriate biosecurity procedures.

Matches and mismatches between conservation investments and biodiversity values in the European Union.

Recently, the European Commission adopted a new strategy to halt the loss of biodiversity. Member states are expected to favor a more effective collection and redistribution of European Union (EU) funds under the current Multiannual Financial Framework for 2014-2020. Because of the large spatial variation in the distribution of biodiversity and conservation needs at the continental scale, EU instruments should ensure that countries with higher biodiversity values get more funds and resources for the conservation than other countries. Using linear regressions, we assessed the association between conservation investments and biodiversity values across member states, accounting for a variety of conservation investment indicators, taxonomic groups (including groups of plants, vertebrates, and invertebrates), and indicators of biodiversity value. In general, we found clear overall associations between conservation investments and biodiversity variables. However, some countries received more or less investment than would be expected based on biodiversity values in those countries. We also found that the extensive use of birds as unique indicators of conservation effectiveness may lead to biased decisions. Our results can inform future decisions regarding funding allocation and thus improve distribution of EU conservation funds.

Global thermal niche models of two European grasses show high invasion risks in Antarctica.

The two non-native grasses that have established long-term populations in Antarctica (Poa pratensis and Poa annua) were studied from a global multidimensional thermal niche perspective to address the biological invasion risk to Antarctica. These two species exhibit contrasting introduction histories and reproductive strategies and represent two referential case studies of biological invasion processes. We used a multistep process with a range of species distribution modelling techniques (ecological niche factor analysis, multidimensional envelopes, distance/entropy algorithms) together with a suite of thermoclimatic variables, to characterize the potential ranges of these species. Their native bioclimatic thermal envelopes in Eurasia, together with the different naturalized populations across continents, were compared next. The potential niche of P. pratensis was wider at the cold extremes; however, P. annua life history attributes enable it to be a more successful colonizer. We observe that particularly cold summers are a key aspect of the unique Antarctic environment. In consequence, ruderals such as P. annua can quickly expand under such harsh conditions, whereas the more stress-tolerant P. pratensis endures and persist through steady growth. Compiled data on human pressure at the Antarctic Peninsula allowed us to provide site-specific biosecurity risk indicators. We conclude that several areas across the region are vulnerable to invasions from these and other similar species. This can only be visualized in species distribution models (SDMs) when accounting for founder populations that reveal nonanalogous conditions. Results reinforce the need for strict management practices to minimize introductions. Furthermore, our novel set of temperature-based bioclimatic GIS layers for ice-free terrestrial Antarctica provide a mechanism for regional and global species distribution models to be built for other potentially invasive species.

Assessing vulnerability of reptile hotspots through temporal trends of global change factors in the Iberian Peninsula.

Habitat degradation and climate change are major threats to the long-term persistence of reptile populations. However, their roles on primary productivity instability remain unclear at certain scales. Besides, the design of protected areas has often overlooked reptiles or assumed that their ecological requirements are represented under the umbrella of more charismatic species. Here, we assess the vulnerability of areas of high diversity of reptiles in the Iberian Peninsula to global change using data from satellite imagery. We focused on primary productivity, climate and land-use change because they are indicators of environmental variability that might impair ecosystem functioning and alter wildlife communities. We used linear regressions to detect monotonic temporal trends in primary productivity (through the enhanced vegetation index, EVI) and climate (mean temperature and accumulated precipitation) at two spatial resolutions (10-km2 UTM squares and CORINE land-cover polygon level) over the period 2000-2020. We also determined how the strength of land-use and climate change affected the intensity of change in primary productivity at both spatial scales with multivariate linear regressions. We identified 339 hotspots (10-km2 UTM squares) and monotonic increments of temperature, EVI or both occurred in 43 %, 16 % and 22 % of them, respectively. Positive trends of the EVI were related to increasing temperatures and changes in shrubland and forest cover. Within the hotspots with monotonic increments in EVI and temperature, EVI increments occurred in 65 % of the CORINE polygons that did not change their land-cover type, with stronger increases in tree crops. Finally, the Natura 2000 network provides only moderate protection to reptile hotspots, being most of the vegetation types relatively underrepresented. The proportion of forest and shrubland protected by the Natura 2000 network was higher in hotspots where EVI changed. Our procedures are relevant to prioritize hotspots requiring ground monitoring that allows economic and time savings.

Ammonium effects on oxidative stress, telomere length, and locomotion across life stages of an anuran from habitats with contrasting land-use histories.

Understanding the mechanistic implications behind wildlife responses to global changes is a central topic in eco-evolutionary research. In particular, anthropic pollution is known to impact wild populations across the globe, which may have even stronger consequences for species with complex life cycles. Among vertebrates, amphibians represent a paradigmatic example of metamorphosis, and their characteristics make them highly vulnerable to pollution. Here, we tested for differences in the redox status, telomere length, and locomotor performance across life stages of green frogs (Pelophylax perezi) from agrosystem and natural habitats, both constitutively and in response to an experimental ammonium exposure (10 mg/L). We found that larvae from the agrosystem constitutively showed an enhanced redox status (better antioxidant balance against H2O2, lower lipid peroxidation) but shorter telomeres as compared to larvae from the natural environment. The larval redox response to ammonium was, overall, similar in both habitats. In contrast, after metamorphosis, the redox status of individuals from the natural habitat seemed to cope better with ammonium exposure (denoted by lower lipid peroxidation), and differences between habitats in telomere length were no longer present. Intriguingly, while the swimming performance of larvae did not correlate with individual's physiology, metamorphs with lower glutathione reductase activity and longer telomeres had a better jumping performance. This may suggest that locomotor performance is both traded off with the production of reactive oxygen species and potentiated directly by longer telomeres or indirectly by the mechanisms that buffer their shortening. Overall, our study suggests that contrasting land-use histories can drive divergence in physiological pathways linked to individual health and lifespan. Since this pattern was life-stage dependent, divergent habitat conditions can have contrasting implications across the ontogenetic development of species with complex life cycles.

Time measurement validity and reliability of the 4 × 10-m shuttle run test in adult population: The ADULT-FIT project.

OBJECTIVES: The purpose of this study was to analyze the time measurement validity and reliability (between raters and test-retest) of the 4 × 10-m shuttle run test to assess motor fitness in adults, according to gender, age, and physical activity levels. DESIGN: Cross-sectional. A total of 230 adults (86 women) aged 18-64 years participated in the study. METHODS: The time taken to complete the 4 × 10-m shuttle run test was recorded simultaneously by a trained and an untrained rater (inter-rater reliability) and by photoelectric cells (time measurement validity). 48-72 h later, the test was repeated under the same conditions (test-retest reliability). RESULTS: The systematic error for trained rater vs. photocell was close to zero (0.0125, p < 0.01), with an effect size of 0.006; and for both, untrained rater vs. photocell and trained rater vs. untrained rater was ∼0.2 s (p < 0.001) with an effect size of 0.09. For the test-retest reliability, the systematic error was 0.05 s (p < 0.001), with an effect size of 0.26, the intraclass correlation coefficient was 0.998 and the coefficient of variation reported a variability of 0.73 %. Results were not influenced by gender and age, while these improved for active vs. non-active participants. CONCLUSIONS: Findings indicate that measurements with trained raters are a valid and reliable method for assessing the 4 × 10-m shuttle run test in adults. It is highly recommended that raters be trained to minimize the measurement error.

Carryover effects of chronic exposure to ammonium during the larval stage on post-metamorphic frogs.

Water contamination poses an important challenge to aquatic fauna, including well-documented effects on amphibian larvae. However, little is known about how contamination during the larval stages may affect post-metamorphic phases, or whether resistance may have evolved in some populations. In this work, we tested the hypothesis that chronic exposure to ammonium (a common contaminant in agroecosystems with confirmed effects on anuran tadpoles) during the larval stage of Pelophylax perezi frogs would affect growth and locomotor performance of metamorph, juvenile, subadult and adult stages. We also predicted that the effects of ammonium would be milder in offspring originated from parental agroecosystem frogs than those originating from forests. We compared tadpoles from both habitats either reared in untreated water or chronically exposed to ammonium. We found that exposure to ammonium during the larval stage inflicted effects on morphology (different measures of body size) and swimming speed after metamorphosis until adulthood. However, these effects were not always consistent through post-metamorphic stages and the effects differed as a function of treatment and habitat. In adults, body size and condition were greater in non-ammonium and ammonium exposed individuals, respectively. These differences were not detectable in metamorphs, for which only ammonium-exposed individuals from agroecosystem showed reduced body size in intermediate post-metamorphic stages. In turn, treatment reduced jumping distance only in agroecosystem adults, subadults and juveniles, which was opposite to the trend observed just after metamorphosis. These changes of patterns throughout the ontogeny of P. perezi could be due to processes such as compensatory growth, delayed energy costs derived from it, or early sexual differences that could be present even before they can be accounted for. In summary, this study suggests that exposure to ammonium during larval stages can result in diverse biological and long-term outcomes in later life stages.

Direct and indirect effects of chronic exposure to ammonium on anuran larvae survivorship, morphology, and swimming speed.

Several constituents of the current global change are usually deemed accountable for the worldwide declines of amphibian populations. Among these, water contamination poses a major threat, especially to larval stages, which are unable to escape a polluted water body. This problem is remarkable in agrosystems, one of the main sources of water pollution and whose area is forecasted to increase in the forthcoming decades. However, pollutants represent a selective pressure that may result in tolerance in affected areas. In this work, we tested whether chronic exposure to a sublethal concentration of ammonium (10 mg/L), one of the most frequent agrochemicals, affects differently hatching success, survivorship, morphology and swimming performance of Pelophylax perezi tadpoles from agrosystem and pine grove habitats. Ammonium diminished survivorship at the earliest stages after hatching. Thus, lower density was a by-product of exposure to ammonium. Higher density slowed down development, reduced snout-vent length, and had a sharper negative effect on body mass and tail length and depth of ammonium treated individuals with respect to the control. In turn, ammonium accelerated development and increased body mass, SVL, and tail length and depth. These effects did not depend on provenance habitat. However, only pine grove tadpoles' swimming speed was negatively affected by ammonium, which supports the hypothesis that agrosystem tadpoles are more tolerant to ammonium. Finally, corroborating previous findings, tadpoles with larger bodies and tails were faster swimmers, whereas proportionally more massive individuals were slower, and tail depth was unrelated to swimming speed.

Long-term sex-dependent inflammatory response of adult frogs to ammonium exposure during the larval stage.

Among others, the global change involves a worldwide increase in cropland area, with the concomitant rise in nitrogenous fertilizer supplementation and species range alterations, including parasites and pathogens. As most animals rely on their immune systems against these infectious agents, studying the potential effects of nitrogenous compounds on animal immune response is vital to understand their susceptibility to infections under these altered circumstances. Being subjected to an alarming process of global declines, amphibians are the object of particular attention, given their sensitivity to these compounds, especially to ammonium. Moreover, whereas adults can actively avoid polluted patches, larvae are confined within their waterbodies, thus exposed to contaminants in it. In this work, we test whether chronic exposure to a sublethal dose of ammonium during the larval stage of Pelophylax perezi frogs, released from all contamination after metamorphosis, leads to impaired inflammatory response to phytohemagglutinin in adults. We also test whether such a response differs between agrosystem individuals as compared with conspecifics from natural habitats. We found negative carryover effects of chronic exposure of larvae to ammonium on adult inflammatory response, which could imply a greater susceptibility to pathogens and parasites. However, this damage is only true for males, which, according to the immunocompetence handicap hypothesis, could be a consequence of a testosterone-triggered impairment of male immune function. In disagreement with our prediction, however, we detected no differences in the inflammatory response of agrosystem frogs to phytohemagglutinin as compared with natural habitat conspecifics.

Moss establishment success is determined by the interaction between propagule size and species identity.

Colonization of new habitat patches is a key aspect of metacommunity dynamics, particularly for sessile organisms. Mosses can establish in new patches through fragmentation, with different vegetative structures acting as propagules. Despite the importance of these propagules for successful colonization the specific aspects that favour moss colonization by vegetative propagules remain poorly understood, including the effect of propagule size. We examine the intra- and interspecific variation of establishment and colonization success in culture of propagules of different sizes in six widespread soil moss species of contrasting growth form (Dicranum scoparium, Homalothecium aureum, Hypnum cupressiforme, Ptychostomum capillare, Syntrichia ruralis and Tortella squarrosa). We obtained three different size classes of propagules from artificially fragmented vegetative material, and assessed their establishment under controlled light and temperature conditions. We characterize the size, shape, apparent viability, morphological type and size changes due to hydration states of the propagules, all of them traits with potentially significant influence in their dispersal pattern and establishment. Then we assess the effect of these traits on moss establishment, using indicators of surface establishment (number of established shoots and colonized surface) and biomass production (viable biomass) as proxies of colonization success. The establishment indicators related to colonization surface and biomass production differ among species and propagule sizes. The magnitude of the interspecific differences of all indicators of establishment success was larger at the smaller propagule size class. T. squarrosa was the most successful species, and D. scoparium showed the lowest performance. We also found interspecific differences in the hydration dynamics of the propagules. The process of establishment by vegetative fragments operates differently among moss species. Besides, differences between hydration states in propagules of some species could be part of syndromes for both dispersal and establishment. This study unveils several functional traits relevant for moss colonization, such as wet versus dry area and length of fragments, which may improve our understanding of their spatial dynamics.

Integrative analyses of speciation and divergence in Psammodromus hispanicus (Squamata: Lacertidae).

BACKGROUND: Genetic, phenotypic and ecological divergence within a lineage is the result of past and ongoing evolutionary processes, which lead ultimately to diversification and speciation. Integrative analyses allow linking diversification to geological, climatic, and ecological events, and thus disentangling the relative importance of different evolutionary drivers in generating and maintaining current species richness. RESULTS: Here, we use phylogenetic, phenotypic, geographic, and environmental data to investigate diversification in the Spanish sand racer (Psammodromus hispanicus). Phylogenetic, molecular clock dating, and phenotypic analyses show that P. hispanicus consists of three lineages. One lineage from Western Spain diverged 8.3 (2.9-14.7) Mya from the ancestor of Psammodromus hispanicus edwardsianus and P. hispanicus hispanicus Central lineage. The latter diverged 4.8 (1.5-8.7) Mya. Molecular clock dating, together with population genetic analyses, indicate that the three lineages experienced northward range expansions from southern Iberian refugia during Pleistocene glacial periods. Ecological niche modelling shows that suitable habitat of the Western lineage and P. h. edwardsianus overlap over vast areas, but that a barrier may hinder dispersal and genetic mixing of populations of both lineages. P. h. hispanicus Central lineage inhabits an ecological niche that overlaps marginally with the other two lineages. CONCLUSIONS: Our results provide evidence for divergence in allopatry and niche conservatism between the Western lineage and the ancestor of P. h. edwardsianus and P. h. hispanicus Central lineage, whereas they suggest that niche divergence is involved in the origin of the latter two lineages. Both processes were temporally separated and may be responsible for the here documented genetic and phenotypic diversity of P. hispanicus. The temporal pattern is in line with those proposed for other animal lineages. It suggests that geographic isolation and vicariance played an important role in the early diversification of the group, and that lineage diversification was further amplified through ecological divergence.

Niche differentiation between deeply divergent phylogenetic lineages of an endemic newt: implications for Species Distribution Models.

Species distribution models (SDMs) treat species as a single unit, neglecting intraspecific variation. Few studies address the impact of intraspecific variation on SDM performance, and none of them account for the well-known inter-algorithm variability in prediction performance. The endemic Iberian amphibian Lissotriton boscai comprises two geographically highly structured phylogenetic lineages, which allowed us to explore how intraspecific variation affects the overall performance of SDMs and the predicted ecological niche. We built species and lineage distribution models using three different presence-only algorithms. We also tested for niche overlap, niche equivalency and niche similarity, using an ordination technique. We found differences in the predicted potential distribution of the two lineages and the underlying environmental factors. Moreover, intraspecific differences in model predictive capacity existed irrespective of which algorithm was used to build the distribution models. This was coupled with lineages showing a low degree of niche overlap and occurring in relatively different environmental niches spaces. The intraspecific variation observed in L. boscai led to an improved intraspecific predictivity of the lineage level based-distribution models. There was partial spatial agreement between the niche overlap and independently reported secondary contact zones. Thus SDMs built only at the species level may be too naive to predict impacts of global change on species distributions.

Niche models at inter- and intraspecific levels reveal hierarchical niche differentiation in midwife toads.

Variation and population structure play key roles in the speciation process, but adaptive intraspecific genetic variation is commonly ignored when forecasting species niches. Amphibians serve as excellent models for testing how climate and local adaptations shape species distributions due to physiological and dispersal constraints and long generational times. In this study, we analysed the climatic factors driving the evolution of the genus Alytes at inter- and intraspecific levels that may limit realized niches. We tested for both differences among the five recognized species and among intraspecific clades for three of the species (Alytes obstetricans, A. cisternasii, and A. dickhilleni). We employed ecological niche models with an ordination approach to perform niche overlap analyses and test hypotheses of niche conservatism or divergence. Our results showed strong differences in the environmental variables affecting species climatic requirements. At the interspecific level, tests of equivalence and similarity revealed that sister species were non-identical in their environmental niches, although they neither were entirely dissimilar. This pattern was also consistent at the intraspecific level, with the exception of A. cisternasii, whose clades appeared to have experienced a lower degree of niche divergence than clades of the other species. In conclusion, our results support that Alytes toads, examined at both the intra- and interspecific levels, tend to occupy similar, if not identical, climatic environments.

Simulated predation pressure in Pelobates cultripes tadpoles modulates morphology at the metamorphic stage.

Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes. Predators exert a major impact on prey fitness. Although direct consumption entails the greatest effect, predators can affect prey by means of other mechanisms. For instance, injuries inflicted by failed predation attempts can jeopardize prey fitness, even beyond the short-term. In anuran tadpoles, failed predation typically results in partial tail loss, which is known to reduce swimming speed. However, the potential consequences of tadpole partial tail loss after metamorphosis remain understudied. Because tail materials could be important in conforming metamorph body, we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes. We clipped 55% tail length of pre-tail-resorption stage anesthetized tadpoles, and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls. Also, we tested whether tail length correlated with metamorph body size of individuals of the control groups. Tail-clipped tadpoles produced smaller metamorphs than both controls (the bdy size of metamorphs from both controls was similar), which could incur costs in mid-term survival or time to first reproduction. This effect could be particularly important in areas with introduced predators, if autochthonous tadpoles lack defenses against them. Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body, according to the negative effect of shorter tails in a correlational analysis, and clipped tails in an experimental test, on metamorph body size.

Microhabitat selection in the common lizard: implications of biotic interactions, age, sex, local processes, and model transferability among populations.

Modeling species' habitat requirements are crucial to assess impacts of global change, for conservation efforts and to test mechanisms driving species presence. While the influence of abiotic factors has been widely examined, the importance of biotic factors and biotic interactions, and the potential implications of local processes are not well understood. Testing their importance requires additional knowledge and analyses at local habitat scale. Here, we recorded the locations of species presence at the microhabitat scale and measured abiotic and biotic parameters in three different common lizard (Zootoca vivipara) populations using a standardized sampling protocol. Thereafter, space use models and cross-evaluations among populations were run to infer local processes and estimate the importance of biotic parameters, biotic interactions, sex, and age. Biotic parameters explained more variation than abiotic parameters, and intraspecific interactions significantly predicted the spatial distribution. Significant differences among populations in the relationship between abiotic parameters and lizard distribution, and the greater model transferability within populations than between populations are in line with effects predicted by local adaptation and/or phenotypic plasticity. These results underline the importance of including biotic parameters and biotic interactions in space use models at the population level. There were significant differences in space use between sexes, and between adults and yearlings, the latter showing no association with the measured parameters. Consequently, predictive habitat models at the population level taking into account different sexes and age classes are required to understand a specie's ecological requirements and to allow for precise conservation strategies. Our study therefore stresses that future predictive habitat models at the population level and their transferability should take these parameters into account.

Geographical and temporal body size variation in a reptile: roles of sex, ecology, phylogeny and ecology structured in phylogeny.

Geographical body size variation has long interested evolutionary biologists, and a range of mechanisms have been proposed to explain the observed patterns. It is considered to be more puzzling in ectotherms than in endotherms, and integrative approaches are necessary for testing non-exclusive alternative mechanisms. Using lacertid lizards as a model, we adopted an integrative approach, testing different hypotheses for both sexes while incorporating temporal, spatial, and phylogenetic autocorrelation at the individual level. We used data on the Spanish Sand Racer species group from a field survey to disentangle different sources of body size variation through environmental and individual genetic data, while accounting for temporal and spatial autocorrelation. A variation partitioning method was applied to separate independent and shared components of ecology and phylogeny, and estimated their significance. Then, we fed-back our models by controlling for relevant independent components. The pattern was consistent with the geographical Bergmann's cline and the experimental temperature-size rule: adults were larger at lower temperatures (and/or higher elevations). This result was confirmed with additional multi-year independent data-set derived from the literature. Variation partitioning showed no sex differences in phylogenetic inertia but showed sex differences in the independent component of ecology; primarily due to growth differences. Interestingly, only after controlling for independent components did primary productivity also emerge as an important predictor explaining size variation in both sexes. This study highlights the importance of integrating individual-based genetic information, relevant ecological parameters, and temporal and spatial autocorrelation in sex-specific models to detect potentially important hidden effects. Our individual-based approach devoted to extract and control for independent components was useful to reveal hidden effects linked with alternative non-exclusive hypothesis, such as those of primary productivity. Also, including measurement date allowed disentangling and controlling for short-term temporal autocorrelation reflecting sex-specific growth plasticity.

Phenotypic resonance from a single meal in an insectivorous lizard.

Environmental variations are usually thought to require a nonanecdotal intensity or duration to have major effects on individuals and evolutionary outputs. However, environmental variations of weak intensity and short duration could be of major importance when they influence key targets or critical stages. Because conditions experienced early in life can be critical determinants of life history trajectories, especially early nutrition, we tested this hypothesis by experimentally manipulating the first meal of life in the lizard Zootoca vivipara. The species is a live-bearing lizard without parental care, and it consumes small arthropods. Neonates face a great challenge in acquiring their first meal, as is the case in many species that develop skills through learning to capture live prey. We show that this single meal had an overall and long-lasting impact. Effects on dispersal arose within 10 days, and we found effects 1-2 months later on growth, recapture probability, and juvenile survival. Interestingly, we detected effects on reproduction up to 2 years later. Such a "phenotypic resonance" reveals that the influence of small and ephemeral events should not be neglected by evolutionary biologists.

Assessing the congruence of thermal niche estimations derived from distribution and physiological data. A test using diving beetles.

A basic aim of ecology is to understand the determinants of organismal distribution, the niche concept and species distribution models providing key frameworks to approach the problem. As temperature is one of the most important factors affecting species distribution, the estimation of thermal limits is crucially important for inferring range constraints. It is expectable that thermal physiology data derived from laboratory experiments and species' occurrences may express different aspects of the species' niche. However, there is no study systematically testing this prediction in a given taxonomic group while controlling by potential phylogenetic inertia. We estimate the thermal niches of twelve Palaearctic diving beetles species using physiological data derived from experimental analyses in order to examine the extent to which these coincided with those estimated from distribution models based on observed occurrences. We found that thermal niche estimates derived from both approaches lack general congruence, and these results were similar before and after controlling by phylogeny. The congruence between potential distributions obtained from the two different procedures was also explored, and we found again that the percentage of agreement were not very high (~60%). We confirm that both thermal niche estimates derived from geographical and physiological data are likely to misrepresent the true range of climatic variation that these diving beetles are able to tolerate, and so these procedures could be considered as incomplete but complementary estimations of an inaccessible reality.

Ectopic dirofilariosis in two dogs from Rio de Janeiro state, Brazil.

Report of two canine dirofilariosis cases of ectopic location in the state of Rio de Janeiro. This is the first report of erratic migration for this parasitosis in dogs in the state, calling attention to the short period of time between the two cases. The fact that the area is endemic for this parasite, its zoonotic potential and the report of human cases in the state, demonstrates that authorities should be alerted to the control programs of dirofilariosis along with the pathogenic profile of the infections.

Are dispersal-dependent behavioral traits produced by phenotypic plasticity?

Dispersal is a common response to deteriorating conditions such as intense competition, food limitation, predation or parasitism. Although it provides obvious advantages, dispersal is often assumed to be costly. Selection is therefore likely to have acted to decrease these costs, and indeed several studies demonstrated that dispersers and philopatric individuals differ in their morphology, physiology and/or behavior. Using the common lizard (Lacerta vivipara) as our model system, we examined the contribution of phenotypic plasticity to the establishment of dispersal-dependent behavioral traits. We used a reciprocal transplant experiment in which conditions at the maternal site of origin, during offspring development in utero, and at the release site were manipulated. We then compared activity, social interactions and foraging behavior between individuals that stayed philopatric and those that dispersed. Most behavioral traits were also measured at birth and after the dispersal phase.This study demonstrates that (a) 10 months after the dispersal phase, there were still marked behavioral differences between dispersing and philopatric individuals, (b) the reaction when confronted to another individual was also dispersal-status dependent, a result which strongly suggests that individuals are able to recognize the dispersal status of same-age conspecifics and (c) none of the behavioral characteristics were found to be dependent on the environmental conditions (maternal and natal environment) indicating a lack of phenotypic plasticity in the building of the dispersal-dependent behavioral traits examined.