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This research investigates the variable phenomenon of pronoun clitic position in simple lexemes, based on speech and writing samples collected in Nova Iguaçu (RJ). Adopting the theoretical framework of Variationist Sociolinguistics, we intend to determine the social and linguistic factors that trigger the use of proclisis over the use of ênclisis in oral and written forms of language, as well as to recognize which are the most frequent traditional and non-traditional proclisive elements together with the use of proclisis. According to the data analysis, it was possible to bring out the following statements: (a) proclisis proved to be more productive than ênclise, especially in oral language; (b) the proclising element type factor group was the group that most influenced pronominal collocation in both language modalities (oral and written); (c) the speaker's schooling factor group, although it did not control in written language, was also shown to be relevant for pronominal placement; and (d) some other linguistic factors were shown to be relevant, however, divergently in the spoken and written data, showing that their influences depend on the linguistic context in question. [ABSTRACT FROM AUTHOR]

Aim: Many pinniped species have experienced drastic demographic changes due to their interaction with humans. Most studies, however, have failed to detect recent bottlenecks in otariids from genetic data. The South American Sea Lion Otaria flavescens have a long history of population changes associated with interglacial expansion and hunting to almost extinction. This study aimed at investigating these different demographic fluctuations integrating population genetics and phylogeographic approaches. Location: Pacific coast of South America. Methods: Eighty‐five samples from the Chilean coast were collected. Eight microsatellite loci were genotyped, and D‐Loop mitochondrial DNA (mtDNA) sequenced. Genetic diversity was assessed, and tests of recent genetic bottlenecks were performed. Past demographic changes were inferred based on neutrality tests, adjustment of a sudden expansion model and Bayesian skyline plots. The magnitude and timing of the different population size changes were further investigated through approximate Bayesian computation (ABC) of coalescent inferences. Results: The mtDNA shows relatively high diversity (h = 0.98 and π = 0.01) compared to most otariids, corroborates the divergence between Pacific and Atlantic populations, around 80,000 years ago (ya), and revealed a secondary contact zone in the Magellan strait. Microsatellite data support a second genetic discontinuity at 40°S, associated with post‐glacial colonization of Patagonia. ABC analyses confirmed that glaciation affected the effective population size (Ne) all along the Pacific Coast, between ~50,000 and 15,000 ya. A strong reduction of Ne was also inferred for the hunting period (73–66 ya from sampling). Main conclusions: O. flavescens shows clear signatures of susceptibility to climatic and anthropogenic disturbances and a spatial genetic structure that should be taken into account in the context of management and conservation policies. Yet, despite a recent history of demographic bottlenecks, the genetic diversity remains high, likely a consequence of the demographic dynamics in otariids, characterized by large and connected metapopulations. [ABSTRACT FROM AUTHOR]

Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, themost common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation. [ABSTRACT FROM AUTHOR]

The genetic identification of evolutionary significant units and information on their connectivity can be used to design effective management and conservation plans for species of concern. Despite having high dispersal capacity, several seabird species show population structure due to both abiotic and biotic barriers to gene flow. The Kelp Gull is the most abundant species of gull in the southern hemisphere. In Argentina it reproduces in both marine and freshwater environments, with more than 100,000 breeding pairs following a metapopulation dynamic across 140 colonies in the Atlantic coast of Patagonia. However, little is known about the demography and connectivity of inland populations. We aim to provide information on the connectivity of the largest freshwater colonies (those from Nahuel Huapi Lake) with the closest Pacific and Atlantic populations to evaluate if these freshwater colonies are receiving immigrants from the larger coastal populations. We sampled three geographic regions (Nahuel Huapi Lake and the Atlantic and Pacific coasts) and employed a reduced-representation genomic approach to genotype individuals for single-nucleotide polymorphisms (SNPs). Using clustering and phylogenetic analyses we found three genetic groups, each corresponding to one of our sampled regions. Individuals from marine environments are more closely related to each other than to those from Nahuel Huapi Lake, indicating that the latter population constitutes the first freshwater Kelp Gull colony to be identified as an evolutionary significant unit in Patagonia. [ABSTRACT FROM AUTHOR]

The spatial and trophic ecology of the culpeo fox (Lycalopex culpaeus) was studied in the Salar de Punta Negra basin and the Llullaillaco National Park, in the high Andes of the Region of Antofagasta in northern Chile. The objectives of this study were to understand the feeding ecology, habitat use, and home range and activity pattern of culpeo fox. The study was conducted in an area of approximately 2800 km2 inside the Punta Negra salt flat basin, Llullaillaco NP, the surrounding mountains, and within areas of mining operations. We used methodologies including camera trapping, live trapping and satellite monitoring of L. culpaeus individuals, and diet analysis. Fifteen captures and five recaptures of culpeos were made, and three of them were equipped with satellite tracking collars. The home ranges estimated using the Minimum Convex Polygon (MPC 95%) were: 1029 km2 (female), 809 km2 (female) and 215 km2 (male). Culpeo foxes were nocturnal animals. A larger sample of 282 fecal scats was collected, with the main trophic prey in culpeo fox diet by frequency of occurrence being rodents (74.3%), arthropods (48%), camelids carrion (43.6%), birds (16.3%), vegetation (13.8%) and reptiles (2.5%). Niche breadth was low (0.367). [ABSTRACT FROM AUTHOR]

Octodon (Octodontidae) is an endemic genus of rodents that is typical of southwestern South America and represented by 4 species. Octodon pacificus, commonly referred to as the Mocha Island degu, was initially described from specimens collected in 1959 at Mocha Island, a small coastal island located along the central coast of Chile. Fifty-seven years after its original collection, we report the discovery of a female O. pacificus carcass, identified by its morphological characteristics and its specific locality. In addition, based on the cytochrome b (Cytb) gene of the mitochondrial DNA obtained from O. pacificus and other congeneric species, we assessed phylogenetic relationships within the Octodontidae. Bayesian phylogenetic reconstruction indicated that O. degus represented the basal Octodon sp., followed by O. lunatus; O. bridgesii and O. pacificus were identified as sister taxa. Remarkably, the genetic divergence between O. bridgesii and O. pacificus is low, which suggests that 1 of 2 scenarios may be at play: the occurrence of a recent peripatric speciation process in O. pacificus, or the presence of O. bridgesii on Mocha Island. Documented collections of archeozoological material obtained from Mocha Island only include specimens of O. pacificus, a finding that supports our 1st proposed scenario. While the core of Mocha Island is a national reserve, strong anthropogenic landscape modifications have affected the coastal plains-the only known habitat of O. pacificus. Rodent control using killing traps and poison is a common practice on the island; therefore, population surveys and conservation initiatives are needed to conserve this endangered species. [ABSTRACT FROM AUTHOR]

Two main hypotheses have been debated about the biogeography of the Southern Ocean: (1) the Antarctic Polar Front (APF), acting as a barrier between Antarctic and sub-Antarctic provinces, and (2) the Antarctic Circumpolar Current (ACC), promoting gene flow among sub-Antarctic areas. The Gentoo penguin is distributed throughout these two provinces, separated by the APF. We analyzed mtDNA (HVR1) and 12 microsatellite loci of 264 Gentoo penguins, Pygoscelis papua , from 12 colonies spanning from the Western Antarctic Peninsula and the South Shetland Islands (WAP) to the sub-Antarctic Islands (SAI). While low genetic structure was detected among WAP colonies (mtDNA Ф ST = 0.037–0.133; microsatellite F ST = 0.009–0.063), high differentiation was found between all SAI and WAP populations (mtDNA Ф ST = 0.678–0.930; microsatellite F ST = 0.110–0.290). These results suggest that contemporary dispersal around the Southern Ocean is very limited or absent. As predicted, the APF appears to be a significant biogeographical boundary for Gentoo penguin populations; however, the ACC does not promote connectivity in this species. Our data suggest demographic expansion in the WAP during the last glacial maximum (LGM, about 20 kya), but stability in SAI. Phylogenetic analyses showed a deep divergence between populations from the WAP and those from the SAI. Therefore, taxonomy should be further revised. The Crozet Islands resulted as a basal clade (3.57 Mya), followed by the Kerguelen Islands (2.32 Mya) as well as a more recent divergence between the Falkland/Malvinas Islands and the WAP (1.27 Mya). Historical isolation, local adaptation, and past climate scenarios of those Evolutionarily Significant Units may have led to different potentials to respond to climate changes. [ABSTRACT FROM AUTHOR]

The Andean degu, Octodontomys gliroides Gervais & d'Orbigny, 1844, has a broad distribution inhabiting pre-Andean pre-Puna and Puna environments of tropical South America. In order to understand the phylogeographic patterns of Octodontomys gliroides, we sequenced 579 bp of the mitochondrial DNA control region from 100 individuals collected from 20 populations across its entire distributional range. The phylogenetic and parsimony network, in conjunction with analysis of molecular variance ( AMOVA), revealed a structured pattern of geographic differentiation of O. gliroides, with the occurrence of two well-defined evolutionary lineages: lineage A, restricted to Bolivia and Chile, and lineage B, restricted mainly to Argentina. Analysis of population structure inferred three genetic clusters along the distribution of O. gliroides that mostly agree with the four major barriers inferred by BARRIER analysis (e.g. rivers, salt flats, deserts, and mountain systems). In addition to the significant differentiation found among all levels studied, a positive correlation was identified between genetic and geographic distance, similar to as expected under the isolation-by-distance model. The most recent common ancestor of O. gliroides was estimated as c. 5.99 Mya, and the divergence between lineages A and B is estimated to have occurred by the Middle Pleistocene, about 0.69 Mya. The mismatch distributions and neutrality tests suggested a signal of population range expansion for both lineages coincident with major climatic changes that occurred during the wet-dry events of the Pleistocene in the Andean Puna region. Bayesian skyline plots ( BSPs) for lineage A suggest a long history of constant population size followed by a period of slight to moderate demographic expansion at c. 0.04 Mya, whereas lineage B remained unclear after BSP analysis, probably because of the limited sample size. [ABSTRACT FROM AUTHOR]

Purpose: The present study analyzed how an organization justifies the launch of a technological resource for home-office, called the work capsule. Methodology: An instrumental case study was developed, which included the analysis of secondary data composed of videos, articles and documents. Main results: The analysis of the results showed that the focus of the materials related to the launch of the technological resource focused mainly on aspects that benefited the organization and its interests or on the benefits that technology represented for the worker, facing the challenges of remote work. Thus, two main categories emerged from the data analysis: When the home disturbs the office and control of the home(m) to guarantee the office. Practical contributions: a) Support the development of discussions and reflections on policies and legislation that impact the condition of workers in the face of the impetus of the neoliberal digital society. b) Unveil the behavior of a neoliberal organization that, in the face of the negative repercussion of the launch of technology, sought to camouflage its interests, but without dispelling its proposal, indicating a solution to a "new spirit of the home-office" Academic contributions: a) The constitution of a "new spirit of the home-office", which further blurs the nebulous boundaries between work and personal life, now reaching space and demanding new theoretical approaches. b) Advance in studies on technological affordances, pointing to the possibility of a new concept of "resources that monitor their own technological resources", characterizing technological surveillance resources, but of a second level. [ABSTRACT FROM AUTHOR]

The article discusses findings of a study to evaluate species abundance distribution of the Humboldt Penguin or Spheniscus humboldti in Peru and Chile. It notes the impact of the El Niño climate phenomenon on the breeding colonies of Humboldt Penguin in La Foca Island, Peru and in Metalui Island, Chile. It confirms that while Humboldt Penguin population in Punta San Juan, Peru decreased by 51 percent from 1980 to 2008, it increased by 89 percent in Chañaral Island, Chile.

Background: A number of studies have described the extension of ice cover in western Patagonia during the Last Glacial Maximum, providing evidence of a complete cover of terrestrial habitat from 41°S to 56°S and two main refugia, one in south-eastern Tierra del Fuego and the other north of the Chiloé Island. However, recent evidence of high genetic diversity in Patagonian river species suggests the existence of aquatic refugia in this region. Here, we further test this hypothesis based on phylogeographic inferences from a semi-aquatic species that is a top predator of river and marine fauna, the huillín or Southern river otter (Lontra provocax). Results: We examined mtDNA sequences of the control region, ND5 and Cytochrome-b (2151 bp in total) in 75 samples of L. provocax from 21 locations in river and marine habitats. Phylogenetic analysis illustrates two main divergent clades for L. provocax in continental freshwater habitat. A highly diverse clade was represented by haplotypes from the marine habitat of the Southern Fjords and Channels (SFC) region (43°38' to 53°08'S), whereas only one of these haplotypes was paraphyletic and associated with northern river haplotypes. Conclusions: Our data support the hypothesis of the persistence of L. provocax in western Patagonia, south of the ice sheet limit, during last glacial maximum (41°S latitude). This limit also corresponds to a strong environmental change, which might have spurred L. provocax differentiation between the two environments. [ABSTRACT FROM AUTHOR]

The evolutionary history of a species can be revealed by phylogeographical analysis; nevertheless, not only historical but also contemporary processes can imprint on the distribution of genetic diversity. We report on the phylogeny of Lontra ssp. in South America, and the role of spatial heterogeneity in shaping the distribution and population structure of the endangered marine otter, Lontra felina. Analyzing a total of 2261 bp of mitochondrial DNA (mtDNA) revealed the recent divergence of L. felina from L. provocax. A strong population structure (Φst = 0.83, P < 0.0001) and a significant pattern of isolation by distance were described for L. felina (n = 168) across a wide geographical distribution (13°53′S to 43°36′S). Lontra felina mtDNA phylogeny is composed of 2 main clades: a clade from Peru and another composed of Chilean haplotypes. Northern populations show different divergent lineages and higher genetic diversity when compared with more recently colonized southern populations. Furthermore, long sandy beaches seem to act as barriers to dispersal, creating 2 evolutionary significant units in agreement with subspecies previous description, and at least 5 different management units (MUs). At a fine spatial scale, the size of rocky seashore patches, the distance between patches and anthropogenic factors also play important roles in species gene flow. [ABSTRACT FROM PUBLISHER]

The three living species of manatees, West Indian ( Trichechus manatus), Amazonian ( Trichechus inunguis) and West African ( Trichechus senegalensis), are distributed across the shallow tropical and subtropical waters of America and the western coast of Africa. We have sequenced the mitochondrial DNA control region in 330 Trichechus to compare their phylogeographic patterns. In T. manatus we observed a marked population structure with the identification of three haplotype clusters showing a distinct spatial distribution. A geographic barrier represented by the continuity of the Lesser Antilles to Trinidad Island, near the mouth of the Orinoco River in Venezuela, appears to have restricted the gene flow historically in T. manatus. However, for T. inunguis we observed a single expanding population cluster, with a high diversity of very closely related haplotypes. A marked geographic population structure is likely present in T. senegalensis with at least two distinct clusters. Phylogenetic analyses with the mtDNA cytochrome b gene suggest a clade of the marine Trichechus species, with T. inunguis as the most basal trichechid. This is in agreement with previous morphological analyses. Mitochondrial DNA, autosomal microsatellites and cytogenetic analyses revealed the presence of hybrids between the T. manatus and T. inunguis species at the mouth of the Amazon River in Brazil, extending to the Guyanas and probably as far as the mouth of the Orinoco River. Future conservation strategies should consider the distinct population structure of manatee species, as well as the historical barriers to gene flow and the likely occurrence of interspecific hybridization. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex (MHC) is a genetic region in jawed vertebrates that contains key genes involved in the immune response. Associations between the MHC and avian malaria infections in wild birds have been observed and mainly explored in the Northern Hemisphere, while a general lack of information remains in the Southern Hemisphere. Here, we investigated the associations between the MHC genes and infections with Plasmodium and Haemoproteus blood parasites along a latitudinal gradient in South America. We sampled 93 rufous‐collared sparrows (Zonotrichia capensis) individuals from four countries, Colombia, Ecuador, Peru, and Chile, and estimated MHC‐I and MHC‐II allele diversity. We detected between 1–4 (MHC‐I) and 1–6 (MHC‐II) amino acidic alleles per individual, with signs of positive selection. We obtained generalized additive mixed models to explore the associations between MHC‐I and MHC‐II diversity and latitude. We also explored the relationship between infection status and latitude/biome. We found a non‐linear association between the MHC‐II amino acidic allele diversity and latitude. Individuals from north Chile presented a lower MHC genetic diversity than those from other locations. We also found an association between deserts and xeric shrublands and a lower prevalence of Haemoproteus parasites. Our results support a lower MHC genetic in arid or semi‐arid habitats in the region with the lower prevalence of Haemoproteus parasites. [ABSTRACT FROM AUTHOR]

Climate change has physiological consequences on organisms, ecosystems and human societies, surpassing the pace of organismal adaptation. Hibernating mammals are particularly vulnerable as winter survival is determined by short-term physiological changes triggered by temperature. In these animals, winter temperatures cannot surpass a certain threshold, above which hibernators arouse from torpor, increasing several fold their energy needs when food is unavailable. Here, we parameterized a numerical model predicting energy consumption in heterothermic species and modelled winter survival at different climate change scenarios. As a model species, we used the arboreal marsupial monito del monte (genus Dromiciops), which is recognized as one of the few South American hibernators. We modelled four climate change scenarios (from optimistic to pessimistic) based on IPCC projections, predicting that northern and coastal populations (Dromiciops bozinovici) will decline because the minimum number of cold days needed to survive the winter will not be attained. These populations are also the most affected by habitat fragmentation and changes in land use. Conversely, Andean and other highland populations, in cooler environments, are predicted to persist and thrive. Given the widespread presence of hibernating mammals around the world, models based on simple physiological parameters, such as this one, are becoming essential for predicting species responses to warming in the short term. [ABSTRACT FROM AUTHOR]

The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (∼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies ∼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation. [ABSTRACT FROM AUTHOR]

We propose to analyze the consumption of social networks by Brazilian individuals after the start of the pandemic and their perception about the use of their data and attitude towards the terms of consent. Such terms outline the relationship between users and social networks. We developed a survey after the start of the pandemic, with the participation of 516 respondents. Based on the responses, we found that social networks' use increased after the beginning of the pandemic. Besides, almost 40% of respondents believe that the use of their data damages privacy and/or data is not used following current legislation. Even so, among that 40% of respondents, almost 75% never or rarely, read the terms of consent. Also, research shows that among respondents with a higher education level, there are those who least read such terms. [ABSTRACT FROM AUTHOR]

Despite the recent advances in the systematics of snakes, the diversity of several Neotropical groups of species remains poorly understood. The lack of studies focused on the phylogenetic relationship within most of the 20 tribes of Dipsadidae precludes a better understanding of the evolution of this diverse family. Here, we present a comprehensive phylogenetic analysis of Tachymenini, a heterogeneous tribe that comprises 36 viviparous species of dipsadids, grouped in seven genera based on morphological similarities. The tribe is widely distributed throughout South America presenting very distinctive phenotypes, habitats, and behaviours. The phylogenetic relationship among tachymenins is a well‐recognized challenge regarding the systematics of the South American dipsadids. The similar morphotype of some generalist species, combined with the very derived morphology of some strict specialists, creates a complexity of traits that has prevented the comprehension of the systematics of the group. To address such a challenge, we combine molecular (six loci) and morphological (70 characters) datasets in an integrative phylogenetic approach. The resultant phylogenetic trees indicate, with strong support, that three of the seven current recognized genera (Tachymenis, Tomodon, and Thamnodynastes) are non‐monophyletic and, consequently, we propose a new systematic arrangement for Tachymenini. We revalidate two genera, Dryophylax and Mesotes, and we describe three additional monotypic genera, Apographon gen. n., Tachymenoides gen. n., and Zonateres gen. n. to accommodate Tomodon orestes, Tachymenis affinis, and Thamnodynastes lanei, respectively. We also include Tomodon ocellatus and Pseudotomodon trigonatus in Tachymenis and describe a new genus, Galvarinus gen. n., to accommodate the Tachymenis chilensis species group. Furthermore, we also provide an evolutionary scenario for the speciation events based on a time‐calibrated tree, commenting on the diversification and origin of the tribe, and on the probable existence of undescribed species of Mesotes and Dryophylax. [ABSTRACT FROM AUTHOR]

Simple Summary: Chilean waters constitute a foraging habitat for the endangered green turtle. Information about this species in the country has increased in recent years; nevertheless, little is known of its ecology and health status. Additionally, some populations have drastically decreased, probably due to human factors. Here, we studied the proportion of sex, age, morphological variation, genetic characteristics, origin, and health status of green turtles in mainland and insular Chile. We found that turtles from both regions are morphologically and genetically different. Individuals from the mainland territory are juveniles and probably originated from Galapagos. In contrast, the insular territory hosts juveniles and adults that probably originated from Galapagos and French Polynesia. We also found that turtles from both regions are facing numerous anthropic threats that must be controlled. We suggest the creation of protected areas for mainland foraging grounds, and strengthen the administrative plan of the insular region to ensure sea turtle population health. Two divergent genetic lineages have been described for the endangered green turtle in the Pacific Ocean, occurring sympatrically in some foraging grounds. Chile has seven known green turtle foraging grounds, hosting mainly juveniles of different lineages. Unfortunately, anthropic factors have led to the decline or disappearance of most foraging aggregations. We investigated age-class/sex structure, morphological variation, genetic diversity and structure, and health status of turtles from two mainland (Bahia Salado and Playa Chinchorro) and one insular (Easter Island) Chilean foraging grounds. Bahia Salado is composed of juveniles, and with Playa Chinchorro, exclusively harbors individuals of the north-central/eastern Pacific lineage, with Galapagos as the major genetic contributor. Conversely, Easter Island hosts juveniles and adults from both the eastern Pacific and French Polynesia. Morphological variation was found between lineages and foraging grounds, suggesting an underlying genetic component but also an environmental influence. Turtles from Easter Island, unlike Bahia Salado, exhibited injuries/alterations probably related to anthropic threats. Our findings point to establishing legal protection for mainland Chile's foraging grounds, and to ensure that the administrative plan for Easter Island's marine protected area maintains ecosystem health, turtle population viability, and related cultural and touristic activities. [ABSTRACT FROM AUTHOR]

Pacific Ocean rockfishes (genus Sebastes) exhibit extreme variation in life span, with some species being among the most long-lived extant vertebrates. We de novo assembled the genomes of 88 rockfish species and from these identified repeated signatures of positive selection in DNA repair pathways in long-lived taxa and 137 longevity-associated genes with direct effects on life span through insulin signaling and with pleiotropic effects through size and environmental adaptations. A genome-wide screen of structural variation reveals copy number expansions in the immune modulatory butyrophilin gene family in long-lived species. The evolution of different rockfish life histories is coupled to genetic diversity and reshapes the mutational spectrum driving segregating CpG→TpG variants in long-lived species. These analyses highlight the genetic innovations that underlie life history trait adaptations and, in turn, how they shape genomic diversity. [ABSTRACT FROM AUTHOR]

Aim: Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitation even more challenging, potentially resulting in taxonomic inconsistencies. Rockhopper penguins of the genus Eudyptes comprise three broadly recognized taxa: northern (E. moseleyi), southern (E. chrysocome) and eastern rockhopper (E. filholi). Their taxonomic status has been controversial for decades, with researchers disagreeing about whether E. chrysocome and E. filholi are distinct species or conspecific. Our goal is to evaluate genome‐wide patterns of divergence to evaluate genetic differentiation and species delimitation in rockhopper penguins, and to assess which mechanisms may underlie previous discordance among nuclear versus mitochondrial analyses. Location: Sub‐Antarctic and temperate coastal regions of the Southern Hemisphere. Methods: We generated reduced‐representation genomic libraries using double digest restriction‐site associated DNA (ddRAD) sequencing to evaluate genetic differentiation, contemporary migration rates and admixture among colonies of rockhopper penguins. Results: The extent of genetic differentiation among the three taxa was consistently higher than population‐level genetic differentiation found within these and other penguin species. There was no evidence of admixture among the three taxa, suggesting the absence of ongoing gene flow among them. Species delimitation analyses based on molecular data, along with other lines of evidence, provide strong support for the taxonomic distinction of three species of rockhopper penguins. Main conclusions: Our results provide strong support for the existence of three distinct species of rockhopper penguins. The recognition of this taxonomic diversity is crucial for the management and conservation of this widely distributed species group. This study illustrates that widespread dispersive seabird lineages lacking obvious morphological differences may nevertheless have complex evolutionary histories and comprise cryptic species diversity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The prevalence and diversity were higher for Haemoproteus than Plasmodium in Passeriformes. • The haplotype diversity was higher for Plasmodium than Haemoproteus. • Plasmodium and Haemoproteus prevalence were associated with higher avian diversity in the Chilean ecoregions. • Haemoproteus presented more specialist lineages than Plasmodium. • Haemoproteus presented greater genetic differentiation than Plasmodium between the east and west of the Andes mountains. The specialist versus generalist strategies of hemoparasites in relation to their avian host, as well as environmental factors, can influence their prevalence, diversity and distribution. In this paper we investigated the influence of avian host species, as well as the environmental and geographical factors, on the strategies of Haemoproteus and Plasmodium hemoparasites. We determined prevalence and diversity by targeting their cytochrome b (Cytb) in a total of 2,590 passerine samples from 138 localities of Central and South America, and analysed biogeographic patterns and host-parasite relationships. We found a total prevalence of 23.2%. Haemoproteus presented a higher prevalence (15.3%) than Plasmodium (4.3%), as well as a higher diversity and host specificity. We determined that Plasmodium and Haemoproteus prevalences correlated positively with host diversity (Shannon index) and were significantly influenced by bird diversity, demonstrating a possible "amplification effect". We found an effect of locality and the avian family for prevalences of Haemoproteus and Plasmodium. These results suggest that Haemoproteus is more specialist than Plasmodium and could be mostly influenced by its avian host and the Andes Mountains. [ABSTRACT FROM AUTHOR]

Marine speciesmay exhibit genetic structure accompanied by phenotypic differentiation related to adaptation despite their high mobility. Two shape-based morphotypes have been identified for the green turtle (Chelonia mydas) in the Pacific Ocean: the south-central/western or yellow turtle and north-central/ eastern or black turtle. The genetic differentiation between these morphotypes and the adaptation of the black turtle to environmentally contrasting conditions of the eastern Pacific region has remained a mystery for decades. Here we addressed both questions using a reduced-representation genome approach (Dartseq; 9473 neutral SNPs) and identifying candidate outlier loci (67 outlier SNPs) of biological relevance between shape-based morphotypes from eight Pacific foraging grounds (n = 158). Our results support genetic divergence between morphotypes, probably arising from strong natal homing behaviour. Genes and enriched biological functions linked to thermoregulation, hypoxia, melanism, morphogenesis, osmoregulation, diet and reproduction were found to be outliers for differentiation, providing evidence for adaptation of C. mydas to the eastern Pacific region and suggesting independent evolutionary trajectories of the shape-based morphotypes. Our findings support the evolutionary distinctness of the enigmatic black turtle and contribute to the adaptive research and conservation genomics of a long-lived and highly mobile vertebrate. [ABSTRACT FROM AUTHOR]

• Experimental investigation of CFS profiles coupled to trusses (construction phase). • Experimental investigation of full-scale composite ribbed slabs. • Trusses provided a maximum increase of flexural stiffness and strength of 708% and 357%, respectively during construction phase. • Proposal of a design approach to analytically determine the flexural strength of the slabs during serviceability. • Proposed formulation presented 95% accuracy in determining the flexural behavior of the prototypes. • Experimental results and semi-empirical equations indicate that the area of the steel formwork can be fully considered as steel reinforcement for sagging bending moment. By means of a series of full-scale laboratory tests, this research studied the flexural behavior of a composite ribbed slab employing cold-formed steel profiles as formwork before and after concrete casting. An experimental program was devised and separated in two sets of tests. The first set consisted of the execution of four-point bending tests on eight specimens to represent the system during construction, featuring three specimen types; isolated profile, profile with plastic spacers along the channel and a full assembly including the profile, the plastic spacers and a rebar truss. Displacement and strain as a function of load were measured and the data was used to analyze the influence of the different components on the flexural strength and stiffness of the system. On the second set of tests, three ribbed composite slab specimens featuring steel profiles were subjected to four-point bending. Displacement was registered along with strain on the concrete layer. A formulation to determine the flexural strength of the slabs based on Eurocode is presented and compared to experimental observations. The first phase indicates significant increases of flexural strength and stiffness by coupling a truss to the profile and varying the height of the former, namely a maximum increase of 708% in stiffness and 357% in strength. Isolated profiles and profiles with plastic spacers all failed by distortional buckling, while the full assembly specimens failed by instability of the top chord on the trusses. Second phase results show that the analytical prediction is adequate to determine the flexural strength of the prototype slabs, with approximately 95% accuracy for this sample size. All slab specimens failed by plastic hinge formation within the pure moment span. Furthermore, strain measurements on the concrete indicate that the formulae chosen to determine the effective width of the concrete "tee" section is also adequate. [ABSTRACT FROM AUTHOR]

Climate changes during the late Pleistocene influenced the demography and distribution of species in Patagonia. During the last glacial maximum (LGM), ice sheets covered a great extent of the temperate rainforest in the western Patagonian Andes. The persistence of forest species in refugia during the LGM has been debated for many vertebrates, but rarely for birds. The Green-backed Firecrown (Sephanoides sephaniodes) is an important avian pollinator distributed from the south of the Atacama Desert (28°S) to Tierra del Fuego (54°S) in South America. We evaluated the species' evolutionary history, combining molecular data and models for past and current species distribution. Our results show two distinct haplogroups: the genetically diverse North–South clade (NS) restricted to the Mediterranean and coastal temperate regions that exhibits a signature of population expansion after LGM, and the Austral-East clade (AE) confined to the temperate intermountain range, eastern temperate, and sub-Antarctic regions, with lower genetic diversity and evidence of a more recent population expansion. This AE clade and the past distribution models support the species survival in valleys and lowlands south of the ice sheets limit during LGM until the present. A secondary contact zone was observed with haplotypes from the AE clade distributed in low frequency along with the northern areas. Our results support the paleorefugia hypothesis during the LGM with postglacial secondary contact. [ABSTRACT FROM AUTHOR]

Aim: The conservation of biodiversity is hampered by data deficiencies, with many new species and subspecies awaiting description or reclassification. Population genomics and ecological niche modelling offer complementary new tools for uncovering functional units of phylogenetic diversity. We hypothesize that phylogenetically delineated lineages of gentoo penguins (Pygoscelis papua) distributed across Antarctica and sub‐Antarctic Islands are subject to spatially explicit ecological conditions that have limited gene flow, facilitating genetic differentiation, and thereby speciation processes. Location: Antarctica and sub‐Antarctic area. Methods: We identify divergent lineages for gentoo penguins using ddRAD‐seq and mtDNA, and generated species distribution models (SDMs) based on terrestrial and marine parameters. Results: Analyses of our genomic data supports the existence of four major lineages of gentoo penguin: (i) spanning the sub‐Antarctic archipelagos north of the Antarctic Polar Front (APF); (ii) Kerguelen Island; (iii) South America; and (iv) across maritime Antarctic and the Scotia Arc archipelagos. The APF, a major current system around Antarctica, acts as the most important barrier separating regional sister lineages. Our ecological analyses spanning both the terrestrial (breeding sites) and marine (feeding sites) realms recover limited niche overlap among the major lineages of gentoo penguin. We observe this pattern to correspond more closely with regional differentiation of marine conditions than to terrestrial macroenvironmental features. Main conclusions: Recognition of regional genetic lineages as discrete evolutionary entities that occupy distinct ecological niches and also differ morphologically should be considered a priority for conservation. Gentoo penguins provide a good example of how conservation policy can be directly impacted by new insights obtained through the integration of larger genomic datasets with novel approaches to ecological modelling. This is particularly pertinent to polar environments that are among the most rapidly changing environments on earth. [ABSTRACT FROM AUTHOR]

Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connectivity and foraging niche overlap among southern rockhopper penguin colonies of the coast of southern South America using genomic and stable isotope analyses. We found two distinct genetic clusters and detected low admixture between northern and southern colonies. Stable isotope analysis indicated niche variability between colonies, with Malvinas/Falklands colonies encompassing the species entire isotopic foraging niche, while the remaining colonies had smaller, nonoverlapping niches. A recently founded colony in continental Patagonia differed in isotopic niche width and position with Malvinas/Falklands colonies, its genetically identified founder population, suggesting the exploitation of novel foraging areas and/or prey items. Additionally, dispersing individuals found dead across the Patagonian shore in an unusual mortality event were also assigned to the northern cluster, suggesting northern individuals reach southern localities, but do not breed in these colonies. Facilitated by variability in foraging strategies, and especially during unfavorable conditions, the number of dispersing individuals may increase and enhance the probability of founding new colonies. Metapopulation demographic dynamics in seabirds should account for interannual variability in dispersal behavior and pay special attention to extreme climatic events, classically related to negative effects on population trends. [ABSTRACT FROM AUTHOR]

The upwelling hypothesis has been proposed to explain reduced or lack of population structure in seabird species specialized in food resources available at cold-water upwellings. However, population genetic structure may be challenging to detect in species with large population sizes, since variation in allele frequencies are more robust under genetic drift. High gene flow among populations, that can be constant or pulses of migration in a short period, may also decrease power of algorithms to detect genetic structure. Penguin species usually have large population sizes, high migratory ability but philopatric behavior, and recent investigations debate the existence of subtle population structure for some species not detected before. Previous study on Humboldt penguins found lack of population genetic structure for colonies of Punta San Juan and from South Chile. Here, we used mtDNA and nuclear markers (10 microsatellites and RAG1 intron) to evaluate population structure for 11 main breeding colonies of Humboldt penguins, covering the whole spatial distribution of this species. Although mtDNA failed to detect population structure, microsatellite loci and nuclear intron detected population structure along its latitudinal distribution. Microsatellite showed significant Rst values between most of pairwise locations (44 of 56 locations, Rst = 0.003 to 0.081) and 86% of individuals were assigned to their sampled colony, suggesting philopatry. STRUCTURE detected three main genetic clusters according to geographical locations: i) Peru; ii) North of Chile; and iii) Central-South of Chile. The Humboldt penguin shows signal population expansion after the Last Glacial Maximum (LGM), suggesting that the genetic structure of the species is a result of population dynamics and foraging colder water upwelling that favor gene flow and phylopatric rate. Our findings thus highlight that variable markers and wide sampling along the species distribution are crucial to better understand genetic population structure in animals with high dispersal ability. [ABSTRACT FROM AUTHOR]

Spatial subdivision, local extinction and recolonization influence the genetic variation of natural populations. Different levels of population structure can be identified in nature, from panmictic populations, in which high gene flow homogenizes diversity across localities, to metapopulations, where combinations of moderate to high levels of population differentiation and source-sink population dynamics are expected. Gene flow, dispersal and recolonization can be affected by changes in ecological conditions such as climate and resource distribution. Evaluating demographic history is crucial for understanding current population dynamics. We assessed a mitchondrial DNA (mtDNA) control region and microsatellite data for 210 Magellanic Penguins (Spheniscus magellanicus) from 13 breeding colonies on the coastlines of Chile and Argentina, covering a great portion of the species’ distribution. We found high levels of genetic diversity and detected two genetic-geographic regions, Pacific and Atlantic, probably due to interruption of the connection between the oceans during the Last Glacial Maximum (LGM), when several parts of the Magellanic Channel were connected to the continent. The Atlantic ocean colonies showed a slight differentiation between the northern and southern colonies, and the Falkand/Malvinas one seems to be a mix of northern, southern and Pacific colonies. Magellanic Penguins showed intense gene flown among colonies, and exhibited low levels of genetic differentiation in each region. Furthermore, our findings indicate that the Magellanic Penguin experienced a population expansion around 17,500 years ago, which is in agreement with the timing of a decreased sea level and the exposure of the continental shelf along the coast of Argentina and the Falkland/Malvinas Islands at the end of the LGM. Thus, our results suggest that climate changes that affect the sea level in South America can play important roles in the migration of Magellanic Penguins. [ABSTRACT FROM AUTHOR]

Background: Mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. However, selection over mitochondrial DNA (mtDNA) genes has usually been evaluated at the population level. We sequenced by NGS 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distributed from the equator to Antarctica. Signatures of selection of 13 mitochondrial protein-coding genes were evaluated by comparing among species within and among genera (Spheniscus, Pygoscelis, Eudyptula, Eudyptes and Aptenodytes). The genetic data were correlated with environmental data obtained through remote sensing (sea surface temperature [SST], chlorophyll levels [Chl] and a combination of SST and Chl [COM]) through the distribution of these species. Results: We identified the complete mtDNA genomes of several penguin species, including ND6 and 8 tRNAs on the light strand and 12 protein coding genes, 14 tRNAs and two rRNAs positioned on the heavy strand. The highest diversity was found in NADH dehydrogenase genes and the lowest in COX genes. The lowest evolutionary divergence among species was between Humboldt (Spheniscus humboldti) and Galapagos (S. mendiculus) penguins (0.004), while the highest was observed between little penguin (Eudyptula minor) and Adélie penguin (Pygoscelis adeliae) (0.097). We identified a signature of purifying selection (Ka/Ks < 1) across the mitochondrial genome, which is consistent with the hypothesis that purifying selection is constraining mitogenome evolution to maintain Oxidative phosphorylation (OXPHOS) proteins and functionality. Pairwise species maximum-likelihood analyses of selection at codon sites suggest positive selection has occurred on ATP8 (Fixed-Effects Likelihood, FEL) and ND4 (Single Likelihood Ancestral Counting, SLAC) in all penguins. In contrast, COX1 had a signature of strong negative selection. ND4 Ka/Ks ratios were highly correlated with SST (Mantel, p-value: 0.0001; GLM, p-value: 0.00001) and thus may be related to climate adaptation throughout penguin speciation. Conclusions: These results identify mtDNA candidate genes under selection which could be involved in broad-scale adaptations of penguins to their environment. Such knowledge may be particularly useful for developing predictive models of how these species may respond to severe climatic changes in the future. [ABSTRACT FROM AUTHOR]

Bahía Salado, located in northern Chile (27°41'S, 70°59'W), is the southernmost foraging ground for the endangered green turtle (Chelonia mydas) in the Eastern Pacific Ocean (EPO). To date, almost no information exists on its current status, nor on its connectivity with nesting rookeries in the EPO. This study aims to inform on the genetic characterization, health and ecology of Bahía Salado's green turtle aggregation in order to provide baseline information for local conservation strategies. We describe population structure and residency times using mark-recapture method. We also examine health parameters (body condition index, blood profile and blood copper-Cu and lead-Pb concentrations) and regional connectivity through genetic analyses. Our results indicate that this aggregation is composed exclusively of juveniles, with residency times varying between five to sixteen months. Turtles exhibited a very good body condition; however they showed the highest blood concentrations of Cu and Pb described for C. mydas and for almost all sea turtle species. Some biochemistry parameters (albumin, calcium, phosphorus, AST, triglycerides and creatinine) are also the highest ever reported for this species in the region. Analysis of the 770 bp (base pairs) control region of the mitochondrial DNA revealed four haplotypes, suggesting a strong genetic connectivity to the Galapagos rookery. Our study indicates that Bahía Salado's aggregation represents a developmental foraging ground, where juvenile green turtles thrive. Although Bahía Salado's ecosystem seems to be a very suitable habitat for the species, the high levels of Cu and Pb, together with elevated AST, demand further research on the negative impacts of heavy metals on this aggregation. Our results highlight the importance to protect this bay from anthropological activities, evaluate pollution sources and other local threats to this particular coastal ecosystem. We recommend year-round monitoring of the green turtle aggregation and other components of this ecosystem, incorporating participation of local seaweed collectors and the fishing community. [ABSTRACT FROM AUTHOR]

Bahía Salado, located in northern Chile (27°41'S, 70°59'W), is the southernmost foraging ground for the endangered green turtle (Chelonia mydas) in the Eastern Pacific Ocean (EPO). To date, almost no information exists on its current status, nor on its connectivity with nesting rookeries in the EPO. This study aims to inform on the genetic characterization, health and ecology of Bahía Salado's green turtle aggregation in order to provide baseline information for local conservation strategies. We describe population structure and residency times using mark-recapture method. We also examine health parameters (body condition index, blood profile and blood copper-Cu and lead-Pb concentrations) and regional connectivity through genetic analyses. Our results indicate that this aggregation is composed exclusively of juveniles, with residency times varying between five to sixteen months. Turtles exhibited a very good body condition; however they showed the highest blood concentrations of Cu and Pb described for C. mydas and for almost all sea turtle species. Some biochemistry parameters (albumin, calcium, phosphorus, AST, triglycerides and creatinine) are also the highest ever reported for this species in the region. Analysis of the 770 bp (base pairs) control region of the mitochondrial DNA revealed four haplotypes, suggesting a strong genetic connectivity to the Galapagos rookery. Our study indicates that Bahía Salado's aggregation represents a developmental foraging ground, where juvenile green turtles thrive. Although Bahía Salado's ecosystem seems to be a very suitable habitat for the species, the high levels of Cu and Pb, together with elevated AST, demand further research on the negative impacts of heavy metals on this aggregation. Our results highlight the importance to protect this bay from anthropological activities, evaluate pollution sources and other local threats to this particular coastal ecosystem. We recommend year-round monitoring of the green turtle aggregation and other components of this ecosystem, incorporating participation of local seaweed collectors and the fishing community. [ABSTRACT FROM AUTHOR]

The evolutionary and adaptive potential of populations or species facing an emerging infectious disease depends on their genetic diversity in genes, such as the major histocompatibility complex ( MHC). In birds, MHC class I deals predominantly with intracellular infections (e.g., viruses) and MHC class II with extracellular infections (e.g., bacteria). Therefore, patterns of MHC I and II diversity may differ between species and across populations of species depending on the relative effect of local and global environmental selective pressures, genetic drift, and gene flow. We hypothesize that high gene flow among populations of Humboldt and Magellanic penguins limits local adaptation in MHC I and MHC II, and signatures of selection differ between markers, locations, and species. We evaluated the MHC I and II diversity using 454 next-generation sequencing of 100 Humboldt and 75 Magellanic penguins from seven different breeding colonies. Higher genetic diversity was observed in MHC I than MHC II for both species, explained by more than one MHC I loci identified. Large population sizes, high gene flow, and/or similar selection pressures maintain diversity but limit local adaptation in MHC I. A pattern of isolation by distance was observed for MHC II for Humboldt penguin suggesting local adaptation, mainly on the northernmost studied locality. Furthermore, trans-species alleles were found due to a recent speciation for the genus or convergent evolution. High MHC I and MHC II gene diversity described is extremely advantageous for the long-term survival of the species. [ABSTRACT FROM AUTHOR]

The high dispersal ability of seabirds and the absence of geographical barriers has led to high gene flow and reduced population differentiation. Nevertheless, some species with philopatric behavior have restricted gene flow among colonies, revealing a strong population structure. Gulls show widespread colonial behavior, and are long-lived species, which make them a good model for understanding evolutionary processes in seabirds. Previous genetic studies on the Kelp Gull ( Larus dominicanus) have revealed low genetic variability in mitochondrial markers but relatively high genetic variation in a nuclear marker. These observations can be explained by the occurrence of a selective sweep on mtDNA, population genetic bottlenecks or a recent origin of the species. We used microsatellite data to further investigate these hypotheses, mainly by testing for bottleneck events. Low genetic variability ( H = 0.276-0.570) was detected in Kelp Gulls. However, population genetic structure was observed among regions (Chile, Argentina and Brazil), and between continents (South America and Antarctica). The population of the Kelp Gull in South America may have differentiated due to isolation by distance ( r = 0.7273, p = 0.0013), whereas the population in the Antarctic seems to be isolated by non-physical barriers. Bottleneck events were detected in 6 out of 14 colonies studied. These colonies are at the limits of the distribution of the Kelp Gull, and thus experience harsh survival conditions. We believe that the Kelp Gull has a complex history in the southern hemisphere, with a recent origin, followed by bottlenecks and then population expansion. Thus, the genetic diversity found in Kelp Gull is similar to that observed for other species of Laridae. [ABSTRACT FROM AUTHOR]

Comparative whole-genome analyses hold great power to illuminate commonalities and differences in the evolution of related species that share similar ecologies. The mustelid subfamily Lutrinae includes 13 currently recognized extant species of otters, 1–5 a semiaquatic group whose evolutionary history is incompletely understood. We assembled a dataset comprising 24 genomes from all living otter species, 14 of which were newly sequenced. We used this dataset to infer phylogenetic relationships and divergence times, to characterize patterns of genome-wide genealogical discordance, and to investigate demographic history and current genomic diversity. We found that genera Lutra , Aonyx , Amblonyx , and Lutrogale form a coherent clade that should be synonymized under Lutra , simplifying the taxonomic structure of the subfamily. The poorly known tropical African Aonyx congicus and the more widespread Aonyx capensis were found to be reciprocally monophyletic (having diverged 440,000 years ago), supporting the validity of the former as a distinct species. We observed variable changes in effective population sizes over time among otters within and among continents, although several species showed similar trends of expansions and declines during the last 100,000 years. This has led to different levels of genomic diversity assessed by overall heterozygosity, genome-wide SNV density, and run of homozygosity burden. Interestingly, there were cases in which diversity metrics were consistent with the current threat status (mostly based on census size), highlighting the potential of genomic data for conservation assessment. Overall, our results shed light on otter evolutionary history and provide a framework for further in-depth comparative genomic studies targeting this group. • Phylogenomic relationships among the world's otters were resolved • Genera Lutra , Aonyx , Amblonyx , and Lutrogale should be synonymized under Lutra • The tropical African endemic Aonyx congicus was supported as a distinct species • Demographic history varied but common patterns seem related to paleoclimatic cycles de Ferran et al. employ 24 complete genomes of all living otter species to investigate the evolutionary history of this group of semiaquatic mammals. The results shed light on their phylogenomic relationships, taxonomy, demographic history, and current levels of genomic diversity, with implications for the conservation of these threatened species. [ABSTRACT FROM AUTHOR]

The West Antarctic Peninsula (WAP) has been suffering an increase in its atmospheric temperature during the last 50 years, mainly associated with global warming. This increment of temperature trend associated with changes in sea-ice dynamics has an impact on organisms, affecting their phenology, physiology and distribution range. For instance, rapid demographic changes in Pygoscelis penguins have been reported over the last 50 years in WAP, resulting in population expansion of sub-Antarctic Gentoo penguin (P. papua) and retreat of Antarctic Adelie penguin (P. adeliae). Current global warming has been mainly associated with human activities; however these climate trends are framed in a historical context of climate changes, particularly during the Pleistocene, characterized by an alternation between glacial and interglacial periods. During the last maximal glacial (LGM∼21,000 BP) the ice sheet cover reached its maximum extension on the West Antarctic Peninsula (WAP), causing local extinction of Antarctic taxa, migration to lower latitudes and/or survival in glacial refugia. We studied the HRVI of mtDNA and the nuclear intron βfibint7 of 150 individuals of the WAP to understand the demographic history and population structure of P. papua. We found high genetic diversity, reduced population genetic structure and a signature of population expansion estimated around 13,000 BP, much before the first paleocolony fossil records (∼1,100 BP). Our results suggest that the species may have survived in peri-Antarctic refugia such as South Georgia and North Sandwich islands and recolonized the Antarctic Peninsula and South Shetland Islands after the ice sheet retreat. [ABSTRACT FROM AUTHOR]

The Neotropical otter (Lontra longicaudis) is a medium-sized semiaquatic carnivore with a broad distribution in the Neotropical region. Despite being apparently common in many areas, it is one of the least known otters, and genetic studies on this species are scarce. Here, we have investigated its genetic diversity, population structure, and demographic history across a large portion of its geographic range by analyzing 1471 base pairs (bp) of mitochondrial DNA from 52 individuals. Our results indicate that L. longicaudis presents high levels of genetic diversity and a consistent phylogeographic pattern, suggesting the existence of at least 4 distinct evolutionary lineages in South America. The observed phylogeographic partitions are partially congruent with the subspecies classification previously proposed for this species. Coalescence-based analyses indicate that Neotropical otter mitochondrial DNA lineages have shared a rather recent common ancestor, approximately 0.5 Ma, and have subsequently diversified into the observed phylogroups. A consistent scenario of recent population expansion was identified in Eastern South America based on several complementary analyses of historical demography. The results obtained here provide novel insights on the evolutionary history of this largely unknown Neotropical mustelid and should be useful to design conservation and management policies on behalf of this species and its habitats. [ABSTRACT FROM PUBLISHER]

Eastern Rockhopper penguins from Marion Island in the sub-Antarctic region. The cover image relates to the Research Article https://doi.org/10.1111/ddi.13399 "Taxonomy based on limited genomic markers may underestimate species diversity of rockhopper penguins and threaten their conservation" by Frugone et al. [Extracted from the article]

The article presents a study on parasites of wild and domestic carnivores, such as such as Hepatozoon spp., Babesia spp., Leishmania spp., Trypanosoma cruzi, and Spirocerca spp., of Chile. It reports that In Chile, there is limited or null information about their presence, although these parasites have been reported in neighboring countries. The study aimed to determine its presence and importance for dogs and wild foxes.

• Scarce genetic differentiation between Royal and macaroni penguins. • Population differentiation associated to distance between colonies and temperatures. • Macaroni penguins from Antarctic and sub-Antarctic exhibited genetic differentiation. The study of systematics in wide-ranging seabirds can be challenging due to the vast geographic scales involved, as well as the possible discordance between molecular, morphological and behavioral data. In the Southern Ocean, macaroni penguins (Eudyptes chrysolophus) are distributed over a circumpolar range including populations in Antarctic and sub-Antarctic areas. Macquarie Island, in its relative isolation, is home to a closely related endemic taxon — the royal penguin (Eudyptes schlegeli), which is distinguishable from E. chrysolophus mainly by facial coloration. Although these sister taxa are widely accepted as representing distinct species based on morphological grounds, the extent of their genome-wide differentiation remains uncertain. In this study, we use genome-wide Single Nucleotide Polymorphisms to test genetic differentiation between these geographically isolated taxa and evaluate the main drivers of population structure among breeding colonies of macaroni/royal penguins. Genetic similarity observed between macaroni and royal penguins suggests they constitute a single evolutionary unit. Nevertheless, royal penguins exhibited a tendency to cluster only with macaroni individuals from Kerguelen Island, suggesting that dispersal occurs mainly between these neighboring colonies. A stepping stone model of differentiation of macaroni/royal populations was further supported by a strong pattern of isolation by distance detected across its whole distribution range, possibly driven by large geographic distances between colonies as well as natal philopatry. However, we also detected intraspecific genomic differentiation between Antarctic and sub-Antarctic populations of macaroni penguins, highlighting the role of environmental factors together with geographic distance in the processes of genetic differentiation between Antarctic and sub-Antarctic waters. [ABSTRACT FROM AUTHOR]

Background: Parasite prevalence and diversity are determined by the distribution of hosts and vectors and by the interplay among a suite of environmental factors. Distributions of parasite lineages vary based on host susceptibility and geographical barriers. Hemoparasites of the genera Haemoproteus and Plasmodium have wide distributions, and high prevalence and genetic diversity within perching birds (Order Passeriformes). The rufous-collared sparrow (Zonotrichia capensis) is widely distributed in Central and South America across an immense diversity of environments from sea level to more than 4000 meters above sea level. It therefore provides an excellent model to investigate whether altitudinal and latitudinal gradients influence the distribution, prevalence and diversity of haemosporidian parasites, their population structure and the biogeographical boundaries of distinct parasite lineages. Results: We assembled samples from 1317 rufous-collared sparrows spanning 75 locales from across Central and South America (between 9.5°N and 54°S; 10–4655 meters above sea level). We used DNA sequence data from a fragment of the mitochondrial cytochrome b gene (cytb) of Haemoproteus and Plasmodium from 325 positive samples and found prevalences of 22 and 3%, respectively. Haemoproteus exhibited a higher prevalence than Plasmodium but with comparatively lower genetic diversity. We detected a relationship of Plasmodium and Haemoproteus prevalence with altitude and latitude; however, altitude and latitude did not influence parasite diversity. Conclusions: Parasite lineages showed a phylogeographical boundary coincident with the Andes Mountains, although we also observed a north-south disjunction in Peru for Haemoproteus. Haemosporidian distribution was not homogeneous but differed based on latitude and altitude. This is most probably due to environmental factors that have influenced both vector distribution and abundance, as well as parasite development. Our study provides key insights on the distribution of haemoparasite lineages and parasite dynamics within hosts. [ABSTRACT FROM AUTHOR]

Correction to: BMC Evolutionary Biology (2018) 18:9010.1186/s12862-018-1207-0. [ABSTRACT FROM AUTHOR]

Background: Historical factors, demography, reproduction and dispersal are crucial in determining the genetic structure of seabirds. In the Antarctic marine environment, penguins are a major component of the avian biomass, dominant predators and important bioindicators of ecological change. Populations of chinstrap penguins have decreased in nearly all their breeding sites, and their range is expanding throughout the Antarctic Peninsula. Population genetic structure of this species has been studied in some colonies, but not between breeding colonies in the Antarctic Peninsula or at the species' easternmost breeding colony (Bouvetøya). Results: Connectivity, sex-biased dispersal, diversity, genetic structure and demographic history were studied using 12 microsatellite loci and a mitochondrial DNA region (HVRI) in 12 breeding colonies in the South Shetland Islands (SSI) and the Western Antarctic Peninsula (WAP), and one previously unstudied sub-Antarctic island, 3600 km away from the WAP (Bouvetøya). High genetic diversity, evidence of female bias-dispersal and a sign of population expansion after the last glacial maximum around 10,000 mya were detected. Limited population genetic structure and lack of isolation by distance throughout the region were found, along with no differentiation between the WAP and Bouvetøya (overall microsatellite FST = 0.002, p = 0.273; mtDNA FST= − 0.004, p = 0.766), indicating long distance dispersal. Therefore, genetic assignment tests could not assign individuals to their population(s) of origin. The most differentiated location was Georges Point, one of the southernmost breeding colonies of this species in the WAP. Conclusions: The subtle differentiation found may be explained by some combination of low natal philopatric behavior, high rates of dispersal and/or generally high mobility among colonies of chinstrap penguins compared to other Pygoscelis species. [ABSTRACT FROM AUTHOR]