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Invasive alien species are considered the second largest cause of biodiversity loss in the world. Pittosporum undulatum Vent., is a native species to Australia and was introduced to Brazil, currently being considered invasive in several regions. Here we analysed the floral and structural composition of forest fragments with varying degress of biological invasion by P. undulatum and assess the relationship between its presence and community diversity. A phytosociological survey was conducted in disturbed and reference forests within two forest fragments in Southern Brazil, assessing tree species diversity, structural and environmental variables between communities across all ontogenetic stages. We recorded 7554 individuals from 35 botanical families and 87 species at all ontogenetic stages, including adults, saplings, and seedlings. P. undulatum showed the highest importance in the adult and sapling stages. The presence of P. undulatum in the forest community is not affecting the richness and diversity of the fragments when the communities were analysed separately (as disturbed and reference forests), but we may see their effect when all forests were analysed together in different ontogenetic stages. In addition, there was a reduction in basal area with advancing successional stages, contrary to typical patterns found in mature forests. The presence of P. undulatum in the reference forest suggests that this species is invading older, more established forests. [ABSTRACT FROM AUTHOR]

One of the main barriers to restoration is the arrival of diaspores in degraded areas. However, this process can be hampered in open areas without trees in the landscape. For that, artificial perches are used to attract and provide a landing area for avian seed dispersers, to enhance seed rain. Our objective was to evaluate the effect of the distance of artificial perches in relation to a forest fragment on the diversity and composition of seed rain in an agricultural fallow area, including alien invasive plant species. We also aimed to record and characterize the bird species that potentially act as seed dispersers. Thus, we used artificial perches at three different distances from a forest fragment (5, 25, and 50 m). Four seed traps were arranged under the perches at each distance, and four control seed traps were interspersed with these and distanced at 7.5 m. Furthermore, we placed four seed traps inside the forest fragment at 5 m from the edge. We also carried out 80 h of focal observation of the avifauna that used artificial perches. A total of 24 655 seeds were sampled across all treatments. There was a significant difference in seed abundance and richness between artificial perches, control seed traps, and forest seed traps. Seed deposition increased with distance from the forest fragment (50, 25, and 5 m). An ordination procedure indicated the formation of three plant seed communities, with the forest community being most distinct. The invasive exotic species Pittosporum undulatum (Australian cheesewood) was the third most abundant in the seed rain. We observed 24 bird species from 12 families using artificial perches. The Tyrannidae family was the most represented. We showed that artificial perches are efficient structures for attracting birds, increasing the richness and abundance of seed species. Artificial perches at 25 and 50 m were more efficient possibly due to the provision of greater visibility for birds. Therefore, artificial perches are efficient in increasing seed rain in the fallow area but should be used with caution in landscapes with the presence of alien species. These findings contribute to increasing knowledge about overcoming the first barrier to ecological restoration, which is the arrival of diaspores in degraded areas, and showing the importance of birds in this process. [ABSTRACT FROM AUTHOR]

We describe new records of Trichothraupis melanops in five municipalities of Rio Grande do Sul, Brazil. The birds were detected in sporadic expeditions in the Serra do Sudeste and Campanha Gaúcha regions by direct visualization and vocal recognition. One of these records, next to the border with Uruguay, is the southernmost known location for the species in Brazil. This record expands the geographic range of the species in Brazil south by 170 km. We believe that these occurrences are seasonal displacements and do not represent a colonization front with resident populations. [ABSTRACT FROM AUTHOR]

Accurate identification of predator species is a critical requirement to investigate their diet using faecal samples. We used non-invasive sampling and two methods of predator identification to investigate the diets of sympatric carnivores in a highly deforested region of the Brazilian Amazon. Of 108 scats, 81 could be identified at the species level using DNA sequencing and/or trichology. The former performed better than the latter (81.5% vs. 54.3% of the identified samples), and results were quite congruent (89.7% concordance in the 29 samples that could be assessed with both approaches). Nine species were identified, out of which four (crab-eating fox, ocelot, puma and jaguar) presented a sufficient number of samples to allow dietary analyses. The crab-eating fox was the most generalist (BA=0.92); ocelots focused on small- to medium-sized prey; pumas fed mostly on medium-sized items; and jaguars mostly targeted large-sized prey. A considerable overlap was observed between ocelots and pumas in all estimations (O=0.47–0.83). The presence of jaguars in the same region could be driving pumas to select medium- and small-sized prey. The results of this study highlight the importance of reliable predator identification and the need for in-depth ecological studies in areas where carnivore species are sympatric. [ABSTRACT FROM AUTHOR]

A new species of tuco-tuco, genus Ctenomys, is described from sandy soils on the western slopes of the state of Rio Grande do Sul in southern Brazil. This species is distinguished from other named members of this South American endemic genus by several characteristics. Diagnostic traits for this proposed species are a diploid number of 50 chromosomes and an autosomal fundamental number of 68 arms, with the 1st pair much longer than in other related species. Qualitative and quantitative (geometric morphomerrics) analyses of the skull morphology and phylogenetic analysis of the mitochondrial cytochrome-fr gene support species status, especially when compared with phylogenetically related and geographically neighboring species. Populations of this species have a narrow geographic distribution in a small area (~500 km²) that has been suffering from anthropogenic pressure from soybean, pine, and eucalyptus plantations, as well as desertification. This scenario suggests that this species could be characterized as endangered. [ABSTRACT FROM AUTHOR]

Isolated or semi-isolated small populations are commonly found among species, due to a naturally patchy occupancy of suitable habitats or also as a result of habitat alterations. These populations are subject to an increased risk of local extinction because they are more vulnerable to demographic, genetic, and environmental stochasticity. Considering that natural areas have been becoming progressively more fragmented and smaller, understanding the genetic structure and evolutionary dynamics of small populations is critical. Ctenomys lami has 26 karyotypes distributed in a small area (936 km2 ) continually modified by human actions. We assessed the genetic geographical structure of this species, examining 178 specimens sampled on a fine scale, using information from chromosomal variability, mitochondrial DNA control region and cytochrome c oxidase subunit I sequences, and 14 microsatellite loci. The observed isolation-by-distance pattern and a clinal genetic variation suggest a stepping-stone population model. The results did not indicate genetic structuring associated with distinct karyotypes. However, mitochondrial and nuclear molecular markers demonstrated the existence of 2 demes, which are not completely isolated but are probably reinforced by a geographical barrier. The vulnerability of C. lami is greater than previously supposed, and our data support the designation of one Evolutionary Significant Unit and one Management Unit, and also the inclusion of this species' conservation status as vulnerable. [ABSTRACT FROM PUBLISHER]

In subterranean rodents of the genus Ctenomys, excavation activity can be carried out with the claws and forelimbs (scratch-digging) as well as with the skull and incisor teeth (skull-tooth digging). Within the forelimb myoskeletal system, the humerus is a main bone concentrating a large number of muscles and bearing tensions during excavation. The genus Ctenomys is considered primarily a scratch-digger and secondarily a skull-tooth digger. We analysed the humerus ( N = 165) of four species of Ctenomys from southern Brazil, in areas ranging from the soft soils of the first lines of coastal dunes ( Ctenomys flamarioni, Ctenomys minutus), through the sandy fields of the coastal plains ( Ctenomys minutus, Ctenomys lami), on to the hard soils of the southern pampas ‘gaúchos’ fields ( Ctenomys torquatus). The differences in the form (size + shape) were quantified using geometric morphometrics methods and interpreted in the light of myological descriptions. As expected from a phylogenetic and ecological point of view, C. flamarioni had the most divergent shape and larger size among the species analysed, showing a more slender humerus, especially in the head region, than C. lami, C. minutus, and C. torquatus. Crossing the osteology data with the qualitative observations of the musculature, it was possible to detect large differences in the proximal portion of the humerus that could be related to the insertion of important extension muscles of the pectoral–shoulder joints, which could increase force. The comparison of shape differences between the three closely-related species ( C. lami, C. minutus, and C. torquatus) revealed unexpected patterns because C. lami was the species phenetically more distant from C. flamarioni and not C. torquatus as expected from ecological data and phylogenetic relationships. A two-step adaptive path to humeral shapes better fit to digging is postulated where the deltoid crest and epicondylar crest increases precede an articular surface area increase. The absence of sexual dimorphism in C. torquatus is discussed with regard to the optimal size required to dig in hard soils. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 353–367. [ABSTRACT FROM AUTHOR]

The collared tuco-tuco, Ctenomys torquatus Lichtenstein, 1830 (Ctenomyidae), is a subterranean rodent that occurs in grassland habitats of southern Brazil and northern Uruguay. A population of collared tuco-tucos located in Alegrete Municipality, Rio Grande do Sul State, Brazil, has been proposed as a potential new species because of their remarkable differences in chromosome number and their unique patterns of pelage coloration. The aim of this work was to evaluate the degree of genetic differentiation of this population using mitochondrial DNA (mtDNA) sequences and nuclear microsatellite markers, and to describe spatial patterns of genetic diversity for the other 5 populations of C. torquatus in southern Brazil, focusing on patterns of intra- and interpopulation variation in coat color. The analysis of 1,110 base pairs of the mtDNA cytochrome-b (Cytb) gene and 9 nuclear microsatellite loci revealed 7 haplotypes (n = 65) and 48 alleles (n 5 70), respectively. Genetic diversity was moderately low within populations (HE 5 0.40-0.56), and significantly partitioned among locations (RST = 0.21; P , 0.01). Analysis of the microsatellite data suggested that genetic differentiation is consistent with a simple model of isolation by distance (r = 0.56, P < 0.05), and that the population is in equilibrium between gene flow and local genetic drift. The partially reconstructed phylogeny revealed that the haplotypes derived from the Alegrete population were not reciprocally monophyletic, and that there was a lack of structure for coat color and karyotype variation. Thus, the individuals from the Alegrete population fall within the range of variation for C. torquatus, and should not be considered a new species. We suggest that they be considered a local, specialized lineage that could be treated and managed from a conservation perspective as a Management Unit. [ABSTRACT FROM AUTHOR]

Ontogenetic differences between males and females result in sexual dimorphism, but this process is poorly understood in the majority of mammalian taxa. Sexual dimorphism is particularly extreme in the otariids (Carnivora: Otariidae), and to examine the origin, structure, and temporal patterns of otariid morphological diversity, we focus here on 3 otariid species: Arctocephalus australis (southern fur seal), Callorhinus ursinus (northern fur seal), and Otaria byronia (southern sea lion). Our aims are to compare the ontogeny of skull shape across species, and to evaluate the ontogeny of sexual dimorphism, testing the hypothesis that dimorphism arises by extrapolation of a shared ontogeny to the larger sizes that are characteristic of males. We found that dimorphism increased over ontogeny but was not due solely to allometric extrapolation, because different rates of development were found in some species. Specifically, the relationships between changes in shape and size increase were different between sexes in A. australis and O. byronia, but equal in C. ursinus. It is possible to implicate heterochrony in the origins of the modifications undergone during the ontogeny of males and females of A. australis and O. byronia, considering the differences in the rates of development between the sexes of both species, but it is certain that allometric repatterning also is involved in these. [ABSTRACT FROM AUTHOR]

Transformation of habitats for agriculture is one of the main causes of reduction in diversity worldwide. We observed reproductively-active female turtles of Trachemys dorbignyi and their nests from 1995 to 2001 in an intensively farmed area in southern Brazil. The area was selected because of the existence of a previous study done 20 yr earlier in the same locality, which allowed us to evaluate the possible effects of human activities on the reproductive ecology of T. dorbignyi. Nesting occurred between October and January, with most activity in November and December (the warmest months). An average of 31% of the females nested in each year, laying up to three clutches at intervals of about 15 days. The females usually constructed nests between 0,700 and 1100 h and deposited 6 to 19 eggs (mean = 12.1) per nest. Clutch size was strongly correlated with carapace length. The eggs were, on average, 39.3 ± 1.73 mm long and 25.8 ± 0.91 mm wide, with a mean mass of 14.9 ± 1.29 g. Multivariate Analysis of Variance showed that egg size differed from year to year. In spite of the intense human activity, the parameters analyzed were nearly unchanged after two decades. However, aspects such as reproductive success, reduction of nesting sites, and the effects of agrotoxins, which could affect the long-term conservation of the species, were not assessed. [ABSTRACT FROM AUTHOR]

This paper describes variation at 6 microsatellite loci in 107 specimens of Ctenomys minutus from a chromosomal hybrid zone on the coastal plain of southern Brazil. Of the 56 alleles uncovered in this study, 39.2% are exclusive to alternative cytotypes or the contact populations. Clinal variation is not obvious because there are no microsatellite fixed differences among chromosomally divergent populations, but variation at Hai 2 locus is gradual across the zone. The local populations are highly differentiated and structured. The moderate estimated values of gene flow follow an isolation-by-distance model, which predicts concentration of an allele or a homozygous genotype in patches with generations of individuals with limited dispersal and mating by proximity. Analysis of populations distantly localized from the contact zone probably will provide further insights in the genetic relationship among cytotypes. [ABSTRACT FROM AUTHOR]

The development of comet assay for aquatic organisms is of particular relevance in light of the importance of coastal fisheries to several countries around the world. Two of the most common fish species native to southern Brazil are the gray mullet (Mugil sp.) and sea catfish (Netuma sp.) for which we have produced a standardized comet assay using whole erythrocytes taken from samples of these fish. We investigated the potential of the comet assay for monitoring genotoxicity in mullet and sea catfish and made a preliminary investigation of the baseline levels of DNA damage in the erythrocytes of samples of these fish from non-polluted areas as well as assessing the in vitro sensitivity of erythrocyte exposed to 2, 4 and 8×10−5 M of methyl methanesulfonate (MMS) for 1, 2, 6 and 24 h at 25 and 37 °C. Our results show that there was an increase in baseline DNA damage at higher temperatures and that the amount of MMS-induced DNA damage also increased at higher temperatures and that there was a clear dose/time response to treatment with MMS. To assess the possibility of using fish for environmental biomonitoring we also used the comet assay to investigate the in vitro genotoxic effect of MMS on whole blood cells from human donors and found a clear concentration-related effect at all exposure times, findings which agree with those of other workers. This study demonstrates the potential application of the comet assay to erythrocytes of mullets and sea catfish. However, these findings also suggest that temperature could alter both baseline DNA damage in untreated animals and in vitro cell sensitivity towards genotoxic pollutants. [Copyright &y& Elsevier]

Presents a study which examined the chromosomal polymorphism in a species of tuco-tuco or Ctenomys minutus and the dynamics of a narrow hybrid zone between chromosomal races distributed parapatrically on the coastal plan of southeastern Brazil. Adaptive relationships of the cytotypes of the species; Review of related literature; Materials and methods used in the study; Results and discussion.

Describes and compares a species from Brazil called Ctenomys lami with a closely related species C. minutus Nehring 1887. Application of cytogenetic analysis and morphological characters; Background on the genus Ctenomys; Geographic distribution of Ctenomys.

Derived from thermogravimetry (DTG) of pineapple crown fiber and cellulose Pineapple crown fibers have more mass loss stages than cellulose. The incorporated cellulose was obtained by the method described above of extracting cellulose from the pineapple crown and then was added to films at concentrations of 5% (CF5%), 10% (CF10%) and 15% (CF15%); in addition, pure starch films (SF) was used for comparison purposes. Keywords: Biocomposites; eco-friendly; fibers; packaging; sustainability; waste; ; ; ; ; ; EN Biocomposites eco-friendly fibers packaging sustainability waste ZH 8541 8554 14 11/21/22 20221220 NES 221220 Introduction We live in a critical era regarding waste accumulation and misuse of materials due to the depletion of available resources and the direct effects on the environment. [Extracted from the article]

Invasive alien species are recognized as the second leading cause of biodiversity loss and species extinction worldwide, with zoochoric dispersion being a key factor for the success of invasive organisms as they can favor the germination of these species. We performed a study in the southern Brazil involving three generalist species with abundant and wide amount of distribution in Latin America, with the objective of evaluating seed ingestion by positive criteria about its germination. We investigated the role of bird digestion on the germination of a native pioneer species, the Brazilian pepper— Schinus terebinthifolia , an invasive alien species in many parts of the world. We compared the germination of this native with those of the invasive Australian cheesewood (Pittosporum undulatum) concurrently. Interestingly, the effect of potentiating germination was more intense in the introduced species than for the native species. Pitangus sulphuratus is an important potential disperser for the germination of P. undulatum seeds, enabling the colonization of new areas in the Atlantic Forest of southern Brazil. • The positive effect on germination was significant in the alien species seeds, and greater than in the native species. • Pitangus sulphuratus is an important potential disperser for the germination of P. undulatum seeds. • The novelty in using artificial perches as a method for obtaining seeds ingested by birds. [ABSTRACT FROM AUTHOR]

Epidemics have significant impacts on primate populations. In 2016, yellow fever spread rapidly to the most densely populated states of Brazil, resulting in the death of hundreds of humans and thousands of nonhuman primates. The Yellow Fever Surveillance Program (Programa de Vigilância da Febre Amarela) implemented by the Brazilian government was designed to prevent and control yellow fever outbreaks. In 2020, the regional reference laboratory at the Oswaldo Cruz Institute in Rio de Janeiro state in Brazil, responsible for yellow fever diagnosis, gave us access to 24 DNA samples from capuchin monkeys, which had tested negative for yellow fever virus. The samples were all from sites in Brazil where Sapajus nigritus is the only species of capuchin monkey present. We attempted to sequence two mitochondrial molecular markers commonly used for Cebidae, but five samples did not amplify. In this study, we performed additional DNA amplification and the Basic Local Alignment Search Tool (BLAST) to confirm the species identity of the 19 samples, which amplified and identify the taxon of the five samples that had failed to amplify. Among the 19 samples correctly identified as Sapajus, one was not Sapajus nigritus but another Sapajus species. Of the five samples that previously failed to amplify, three were similar to Callicebus nigrifrons, one was similar to Alouatta guariba clamitans, and one failed to amplify successfully for any marker. These findings show an error rate of 5/24 (21%) in the original taxonomic identification. Misidentification occurred at the genus level as well as the species level. Our findings highlight the importance of precise taxonomic classification in obtaining reliable data on the consequences of the yellow fever epidemic for primates. [ABSTRACT FROM AUTHOR]

The genome organization of woodpeckers has several distinctive features e.g., an uncommon accumulation of repetitive sequences, enlarged Z chromosomes, and atypical diploid numbers. Despite the large diversity of species, there is a paucity of detailed cytogenomic studies for this group and we thus aimed to rectify this. Genome organization patterns and hence evolutionary change in the microchromosome formation of four species (Colaptes campestris, Veniliornis spilogaster, Melanerpes candidus, and Picumnus nebulosus) was established through fluorescence in situ hybridization using bacterial artificial chromosomes originally derived from Gallus gallus and Taeniopygia guttata. Findings suggest that P. nebulosus (2n = 110), which was described for the first time, had the most basal karyotype among species of Picidae studied here, and probably arose as a result of fissions of avian ancestral macrochromosomes. We defined a new chromosomal number for V. spilogaster (2n = 88) and demonstrated microchromosomal rearrangements involving C. campestris plus a single, unique hitherto undescribed rearrangement in V. spilogaster. This comprised an inversion after a fusion involving the ancestral microchromosome 12 (homologous to chicken microchromosome 12). We also determined that the low diploid number of M. candidus is related to microchromosome fusions. Woodpeckers thus exhibit significantly rearranged karyotypes compared to the putative ancestral karyotype. [ABSTRACT FROM AUTHOR]

Introduction: Its wide karyotypic variation characterizes the genus Ctenomys, and in Brazil, the genus is distributed in the country's southern, Midwest, and northern regions. Recently, populations of Ctenomys have been found in the Midwest and northern Brazil, with two new lineages named C. sp. "xingu" and C. sp. "central." Methods: This work combines classical cytogenetic and molecular analyses to provide new chromosomal information on the boliviensis group distributed in northern and Midwestern Brazil. This includes the validation of the karyotype of C. bicolor and C. nattereri and the description of the karyotype of C. sp. "xingu" and C. sp. "central." Results: We found three different karyotypes: 2n = 40 for C. bicolor; 2n = 36 for C. nattereri, and specimens from a locality belonging to C. sp. "central"; 2n = 34 for the lineage C. sp. "xingu" and specimens from a locality belonging to C. sp. "central." Furthermore, GTG banding revealed homologous chromosomes between species/lineages and allowed the identification of the rearrangements that occurred, which proved the occurrence of fissions. Conclusion: Considering our results on the variation of 2n in the boliviensis group, we found two possibilities: the first, deduced by parsimony, is that 2n = 36 appeared initially, and two fissions produced gave rise to 2n = 40, and an independent fusion gave rise to 2n = 34 from 2n = 36; moreover, the second explanation is that all karyotypes arose independently. [ABSTRACT FROM AUTHOR]

The Cuculiformes are a family of over 150 species that live in a range of habitats, such as forests, savannas, and deserts. Here, bacterial artificial chromosome (BAC) probes (75 from chicken and 14 from zebra finch macrochromosomes 1–10 +ZW and for microchromosomes 11–28 (except 16)) were used to investigate chromosome homologies between chicken and the squirrel cuckoo (Piaya cayana). In addition, repetitive DNA probes were applied to characterize the chromosome organization and to explore the role of these sequences in the karyotype evolution of P. cayana. We also applied BAC probes for chicken chromosome 17 and Z to the guira cuckoo (Guira guira) to test whether this species has an unusual Robertsonian translocation between a microchromosome and the Z chromosome, recently described in the smooth-billed ani (Crotophaga ani). Our results revealed extensive chromosome reorganization with inter- and intrachromosomal rearrangements in P. cayana, including a conspicuous chromosome size and heterochromatin polymorphism on chromosome pair 20. Furthermore, we confirmed that the Z-autosome Robertsonian translocation found in C. ani is also found in G. guira, not P. cayana. These findings suggest that this translocation occurred prior to the divergence between C. ani and G. guira, but after the divergence with P. cayana. [ABSTRACT FROM AUTHOR]

The biogeographic history of a species results from responses to past and current processes, and understanding those responses at both temporal scales is essential. We explored phylogeographic and current genetic variation structure in Ctenomys flamarioni —a subterranean rodent that inhabits a small region of the coastal plain of Brazil—and contrasted the roles of "present-day niche suitability" versus "historical climate stability" to understand current and past intraspecific genetic diversity. We used both mitochondrial DNA sequences (concatenated Cytb and D-loop , n = 78) and nuclear DNA (9 microsatellites loci, n = 154) molecular markers for individuals across the entire distribution of the species. We used phylogeographic trees, Bayesian clustering, and haplotype networks to explore genetic variation and diversity. We correlated genetic diversity with measures of current niche suitability and potential areas of Late Quaternary paleostability. Phylogeographic patterns confirmed low levels of genetic diversity structured at different hierarchical levels. We also found a weak but significant pattern of isolation by distance, indicating that geographical distance partially modulates genetic differences among populations. We also observed a positive correlation between genetic diversity and climate paleostability for microsatellites at local and regional scales. However, we found no significant association between genetic diversity and niche suitability for microsatellites at local or regional scales. We observed several signatures of bottleneck and population expansion at different geographic scales. Our results suggest that Quaternary climatic fluctuations—acting together with habitat suitability and other contemporary factors—played a fundamental role in elucidating the evolutionary history of the species—including patterns of historical dispersal, and current patterns of habitat occupation and genetic structure. In addition, based on our molecular and environmental data sets from the across the range of the species and considering the restricted endemism of C. flamarioni , we emphasize the urgency of conservation actions to protect this endangered species. [ABSTRACT FROM AUTHOR]

Vanellus (Charadriidae; Charadriiformes) comprises around 20 species commonly referred to as lapwings. In this study, by integrating cytogenetic and genomic approaches, we assessed the satellite DNA (satDNA) composition of one typical species, Vanellus chilensis, with a highly conserved karyotype. We additionally underlined its role in the evolution, structure, and differentiation process of the present ZW sex chromosome system. Seven distinct satellite DNA families were identified within its genome, accumulating on the centromeres, microchromosomes, and the W chromosome. However, these identified satellite DNA families were not found in two other Charadriiformes members, namely Jacana jacana and Calidris canutus. The hybridization of microsatellite sequences revealed the presence of a few repetitive sequences in V. chilensis, with only two out of sixteen displaying positive hybridization signals. Overall, our results contribute to understanding the genomic organization and satDNA evolution in Charadriiform birds. [ABSTRACT FROM AUTHOR]

Recent molecular studies have clarified the overarching taxonomy of capuchin monkeys, but intraspecific genetic diversity remains unexplored for most capuchin species. One example is Sapajus nigritus, the southernmost capuchin monkey, found in Brazil and Argentina; its phenotypic diversity has been recognized as two geographic subspecies, but the intraspecific genetic structure of this taxon is poorly known. Here, we sampled across most of this species' geographic distribution, producing a newly sequenced data set for genetic analyses that included 78 individuals from 14 populations. We investigated the intraspecific diversity, genetic structure, and evolutionary history using three mitochondrial markers. Our results indicated that S. nigritus populations exhibited high levels of genetic structure. We found strong support for two monophyletic clades within this species with a deep phylogenetic split, and clear separation from other related taxa. Vicariance events seem to have played a prevalent role in shaping S. nigritus genetic differentiation. The Paraíba do Sul River may have driven the deep divergence between southern and northern clades, whereas the Tietê River may have had a weaker, more recent effect on the divergence of populations within the southern clade. Research Highlights: Using mitochondrial markers we found support for two major clades within Sapajus nigritus; the Paraíba do Sul River probably acted as a barrier to drive this deep phylogenetic split, estimated to have occurred at 1.56 MaWe recovered the southern S. nigritus clade as sister to a clade of other Sapajus species (S. cay, apella, macrocephalus, robustus, flavius) rather than northern S. nigritus, emphasizing southern and northern clades as distinct phylogenetic unitsS. nigritus D‐loop analysis showed high pairwise populational genetic differentiation and geographic structure; this D‐loop database can now be used for to help identify the geographical origin of illegally traded animals [ABSTRACT FROM AUTHOR]

Climatic changes have caused major environmental restructuring throughout the world's oceans. Marine organisms have responded to novel conditions through various biological systems, including genomic adaptation. Growing accessibility of next-generation DNA sequencing methods to study nonmodel species has recently allowed genomic changes underlying environmental adaptations to be investigated. This study used double-digest restriction-site associated DNA (ddRAD) sequence data to investigate the genomic basis of ecotype formation across currently recognized species and subspecies of bottlenose dolphins (genus Tursiops) in the Southern Hemisphere. Subspecies-level genomic divergence was confirmed between the offshore common bottlenose dolphin (T. truncatus truncatus) and the inshore Lahille's bottlenose dolphin (T. t. gephyreus) from the southwestern Atlantic Ocean (SWAO). Similarly, subspecies-level divergence is suggested between inshore (eastern Australia) Indo-Pacific bottlenose dolphin (T. aduncus) and the proposed Burrunan dolphin (T. australis) from southern Australia. Inshore bottlenose dolphin lineages generally had lower genomic diversity than offshore lineages, a pattern particularly evident for T. t. gephyreus , which showed exceptionally low diversity. Genomic regions associated with cardiovascular, musculoskeletal, and energy production systems appear to have undergone repeated adaptive evolution in inshore lineages across the Southern Hemisphere. We hypothesize that comparable selective pressures in the inshore environment drove similar adaptive responses in each lineage, supporting parallel evolution of inshore bottlenose dolphins. With climate change altering marine ecosystems worldwide, it is crucial to gain an understanding of the adaptive capacity of local species and populations. Our study provides insights into key adaptive pathways that may be important for the long-term survival of cetaceans and other organisms in a changing marine environment. [ABSTRACT FROM AUTHOR]

Simple Summary: In South America, the natural habitats of wild canids have undergone significant environmental disruptions, leading to interactions between these animals and domestic dogs (Canis lupus familiaris). Previous studies have documented hybridization between wild canids and domestic dogs in North America and Europe. However, there have been no reports of such hybridization in South America until now. In 2021, a female canid from Vacaria in Rio Grande do Sul State, Brazil, was brought to the Center for Conservation and Rehabilitation of Wild Animals—Preserves. This animal exhibited unusual phenotypic characteristics, displaying intermediate traits between domestic dogs and wild canids. Based on these observations, we hypothesized that this animal might result from interspecific hybridization. Therefore, this study aimed to test this hypothesis using genetic and cytogenetic approaches. Our analysis suggests that the canid under investigation is a hybrid between the pampas fox and domestic dog, but future studies are necessary to investigate additional cases of this hybridization in nature. Therefore, the combination of genetic and cytogenetic markers proved valuable in elucidating this case of hybridization. To our knowledge, this represents the first documented case of hybridization between these two species. Hybridization between species with different evolutionary trajectories can be a powerful threat to wildlife conservation. Anthropogenic activities, such as agriculture and livestock, have led to the degradation and loss of natural habitats for wildlife. Consequently, the incidence of interspecific hybridization between wild and domestic species has increased, although cases involving species of different genera are rare. In Vacaria, a Southern city in Brazil, a female canid with a strange phenotype, which had characteristics between the phenotype of the domestic dog (Canis familiaris) and that of the pampas fox (Lycalopex gymnocercus), was found. Our analysis suggests that the animal is a hybrid between a domestic dog and a pampas fox, but future studies are necessary to investigate additional cases of this hybridization in nature. This finding worries for the conservation of wild canids in South America, especially concerning Lycalopex species. Hybridization with the domestic dog may have harmful effects on pampas fox populations due to the potential for introgression and disease transmission by the domestic dog. Therefore, future studies to explore the consequences of hybridization on genetics, ecology, and behavior of wild populations will be essential to improve the conservation of this species. [ABSTRACT FROM AUTHOR]

Seabirds are of considerable conservation significance due to their key role in ecosystems and their generally high level of threat, especially from invasive species in breeding sites and as a result of bycatch during commercial fishing activities. We examined the genetic diversity, evidence for a bottleneck, and effective population size (Ne) of Redbilled Tropicbirds (Phaethon aethereus) from the Abrolhos Archipelago and White-tailed Tropicbirds (P. lepturus) from Fernando de Noronha Archipelago, both in the southwestern Atlantic Ocean. In addition, intraspecific genetic distance was assessed between 2 Red-billed Tropicbirds breeding on Fernando de Noronha and the larger population on Abrolhos, and between 5 White-tailed Tropicbird individuals breeding on Abrolhos and the breeding population on Fernando de Noronha, to identify relict populations. From 11 microsatellite loci, observed heterozygosity was 0.471 for White-tailed Tropicbirds and 0.267 for Red-billed Tropicbirds. Additionally, We was estimated to be as low as 100-200 individuals for each species, ~25-50% of recent census estimates for the largest population of each species. No deviation from mutation-drift equilibrium was detected, but both species had M-ratios indicative of populations that had experienced a bottleneck or been recently established, and seem to have persisted as small populations over the past few centuries on both archipelagos. Small population size coupled with low evolutionary potential make these populations vulnerable to extinction. In our study sites and worldwide, tropicbirds show slow population growth and vulnerability to introduced predators. These species would benefit from both colony-based management and a better understanding of patterns of genetic diversity within and among populations. [ABSTRACT FROM AUTHOR]

Elasmobranchs are threatened and eDNA metabarcoding is a powerful tool that can help efforts to better understand and conserve them. Nevertheless, the inter‐calibration between optimal methodological practices and its implementation in resource‐limited situations is still an issue. Based on promising results from recent studies, the authors applied a cost‐effective protocol with parameters that could be easily replicated by any conservationist. Nonetheless, the results with fewer elasmobranchs detected than expected reveal that endorsed primers and sampling strategies still require further optimization, especially for applications in resource‐limited conservation programmes. [ABSTRACT FROM AUTHOR]

Aim: The use of landscape resistance maps to model connectivity has become an indispensable tool for species conservation. However, different methods can be used to estimate landscape resistance, but there is no consensus on which is the most reliable one. Therefore, comparing the performance of those methods in predicting resistance can be quite useful to understand their limitations and conservation implications. Our goal was to evaluate the accuracy of two commonly used approaches, habitat suitability modelling and landscape genetics, in estimating landscape resistance to genetic connectivity of two species of Neotropical cats (Leopardus guttulus and L. geoffroyi) across their ranges. Location: South America. Taxon: Felidae—L. guttulus and L. geoffroyi. Methods: For both species, we optimized a landscape genetics resistance surface using a restricted multivariate optimization approach and transformed a habitat suitability map into a resistance layer. We compared landscape resistance models created by these two approaches based on the models' Akaike information criterion scores and evaluated the similarities and differences in their predictions by calculating the correlation between the resistance layers and generating difference maps. Results: The genetic approach greatly outperformed the habitat suitability approach in explaining movement driving gene flow for both species. For the studied species, habitat preference and genetic connectivity are influenced by different landscape features. Habitat alteration imposes great resistance for genetic connectivity, and the presence of natural vegetation remnants within altered environments is essential for their conservation. Main conclusions For the studied species, the transformation of habitat suitability models into resistance surfaces is a poor proxy for permeability to dispersal, and the use of genetic data is more reliable in modelling connectivity for species conservation. Habitat suitability and landscape resistance are not equivalent or even proportional for these species. [ABSTRACT FROM AUTHOR]

Aim Subterranean rodents of the genus Ctenomys are widespread in open habitats; the collared tuco-tuco, C. torquatus, has a wide range crossed by large water-courses. Based on a phylogeographical approach to investigate the riverine barrier hypothesis, we evaluated the strength of a river as a barrier and characterized the effect of large rivers in structuring distinct populations of the collared tuco-tuco. Location Grasslands of southern Brazil. Methods Sampling included 294 individuals from 33 localities throughout the geographical range of C. torquatus, especially around the main rivers. Phylogeographical patterns were estimated through two mitochondrial DNA sequences (control region and COI). Additionally, 22 microsatellite loci were surveyed to estimate the effect of rivers on population divergence through the FST index of genetic differentiation and AMOVAs. Spatial autocorrelation analyses were performed for both molecular markers. Molecular rates of change for mitochondrial DNA were estimated using fossil records and applied to Bayesian demographic analysis to test the relationship with the river geological data. Results Molecular-clock analysis estimated the time to most recent common ancestor ( TMRCA) to be c. 200 kyr and indicated a pattern of recent demographic expansion for C. torquatus. Fu's F S neutrality test was significant and negative (−13.7). High and significant FST and AMOVA among-population comparisons ( FSC) revealed highly differentiated populations, although no AMOVA groupings considering rivers as a segregating factor were significant. Spatial autocorrelation analysis revealed that isolation by distance was detected over approximately 200 km. Main conclusions The effect of the river was not proportionally larger from the headwaters to the mouth, and no population differentiation was observed after the later events of dispersal over the river or the formation of a water channel. This finding could result from the recent history of the occupation of C. torquatus in that region, combined with a dry Pleistocene climate and lower river levels. [ABSTRACT FROM AUTHOR]

Subterranean rodents of the genus Ctenomys usually present an allopatric or parapatric distribution. Currently, two cases of sympatry have been recognized for the genus in the coastal dunes of southern Argentina and southern Brazil. In this context, they are ideal models to test hypotheses about the factors that delimit the patterns of space use and to understand interspecific interactions in small mammals. We investigated the vegetation structure, plant biomass and soil hardness selected by two species of subterranean rodents (Ctenomys flamarioni and C. minutus) when distributed in sympatry and allopatry from nine different areas along the line of coastal dunes in southern Brazil. In addition, our work presents a new record of a third area of sympatry for the genus Ctenomys. Ctenomys flamarioni and C. minutus show habitat segregation in the area where they occur in sympatry. These species show segregation in their selection of microhabitats, differing in relation to soil hardness, plant biomass, and plant cover. Ctenomys flamarioni showed a distinction in habitat selection when occurring in allopatry and sympatry, whereas C. minutus selected the same habitat characteristics under both conditions. A possible explanation to the observed pattern is that these species have acquired different adaptations over time which allows them the ability to exploit different resources and thus avoid competitive interactions all together. [ABSTRACT FROM AUTHOR]

The melanocortin 1 receptor (MC1R) is involved in the control of melanogenesis. Polymorphisms in this gene have been associated with variation in skin and hair color and with elevated risk for the development of melanoma. Here we used 11 computational tools based on different approaches to predict the damage-associated non-synonymous single nucleotide polymorphisms (nsSNPs) in the coding region of the human MC1R gene. Among the 92 nsSNPs arranged according to the predictions 62% were classified as damaging in more than five tools. The classification was significantly correlated with the scores of two consensus programs. Alleles associated with the red hair color (RHC) phenotype and with the risk of melanoma were examined. The R variants D84E, R142H, R151C, I155T, R160W and D294H were classified as damaging by the majority of the tools while the r variants V60L, V92M and R163Q have been predicted as neutral in most of the programs The combination of the prediction tools results in 14 nsSNPs indicated as the most damaging mutations in MC1R (L48P, R67W, H70Y, P72L, S83P, R151H, S172I, L206P, T242I, G255R, P256S, C273Y, C289R and R306H); C273Y showed to be highly damaging in SIFT, Polyphen-2, MutPred, PANTHER and PROVEAN scores. The computational analysis proved capable of identifying the potentially damaging nsSNPs in MC1R, which are candidates for further laboratory studies of the functional and pharmacological significance of the alterations in the receptor and the phenotypic outcomes. [ABSTRACT FROM AUTHOR]

Simple Summary: In animals, several species contain substantial chromosomal and genomic variation among their populations, but as to what could have driven such diversification is still a puzzle for most cases. Here, we used molecular cytogenetic analysis to expose the main genomic elements involved in the population variation observed in the Neotropical underground rodents of the genus Ctenomys (Rodentia: Ctenomyidae), which harbor the most significant chromosomal variation among mammals (2n = 10 to 2n = 70). These data provide evidence for a correlation between repetitive genomic content and localization of evolutionary breakpoint regions (EBRs) and highlight their direct impact in promoting chromosomal rearrangements. The Neotropical underground rodents of the genus Ctenomys (Rodentia: Ctenomyidae) comprise about 65 species, which harbor the most significant chromosomal variation among mammals (2n = 10 to 2n = 70). Among them, C. minutus stands out with 45 different cytotypes already identified, among which, seven parental ones, named A to G, are parapatrically distributed in the coastal plains of Southern Brazil. Looking for possible causes that led to such extensive karyotype diversification, we performed chromosomal mapping of different repetitive DNAs, including microsatellites and long interspersed element-1 (LINE-1) retrotransposons in the seven parental cytotypes. Although microsatellites were found mainly in the centromeric and telomeric regions of the chromosomes, different patterns occur for each cytotype, thus revealing specific features. Likewise, the LINE-1-like retrotransposons also showed a differential distribution for each cytotype, which may be linked to stochastic loss of LINE-1 in some populations. Here, microsatellite motifs (A)30, (C)30, (CA)15, (CAC)10, (CAG)10, (CGG)10, (GA)15, and (GAG)10 could be mapped to fusion of chromosomes 20/17, fission and inversion in the short arm of chromosome 2, fusion of chromosomes 23/19, and different combinations of centric and tandem fusions of chromosomes 22/24/16. These data provide evidence for a correlation between repetitive genomic content and localization of evolutionary breakpoints and highlight their direct impact in promoting chromosomal rearrangements. [ABSTRACT FROM AUTHOR]

Investigations of phenotypic disparity across geography often ignore macroevolutionary processes. As a corollary, the random null expectations to which disparity is compared and interpreted may be unrealistic. We tackle this issue by representing, in geographical space, distinct processes of phenotypic evolution underlying ecological disparity. Under divergent natural selection, assemblages in a given region should have empirical disparity higher than expected under an evolutionarily oriented null model, whereas the opposite may indicate constraints on phenotypic evolution. We gathered phylogenies, biogeographic distributions, and data on the skull morphology of sigmodontine rodents to discover which regions of the Neotropics were more influenced by divergent, neutral, or constrained phenotypic evolution. We found that regions with higher disparity than expected by the evolutionary‐oriented null model, in terms of both size and shape, were concentrated in the Atlantic Forest, suggesting a larger role for divergent natural selection there. Phenotypic disparity in the rest of South America, mainly the Amazon basin, northeastern Brazil, and Southern Andes, was constrained—lower than predicted by the evolutionary model. We also demonstrated equivalence between the disparity produced by randomization‐based null models and constrained‐evolution null models. Therefore, including evolutionary simulations into the null modeling framework used in ecophylogenetics can strengthen inferences on the processes underlying phenotypic evolution. [ABSTRACT FROM AUTHOR]

Increased attention towards the Neotropical cats Leopardus guttulus and L. geoffroyi was prompted after genetic studies identified the occurrence of extensive hybridization between them at their geographic contact zone in southern Brazil. This is a region where two biomes intersect, each of which is associated with one of the hybridizing species (Atlantic Forest with L. guttulus and Pampas with L. geoffroyi). In this study, we conducted in-depth analyses of multiple molecular markers aiming to characterize the magnitude and spatial structure of this hybrid zone. We also performed a morphological assessment of these species, aiming to test their phenotypic differentiation at the contact zone, as well as the correlation between morphological features and the admixture status of the individuals. We found strong evidence for extensive and complex hybridization, with at least 40% of the individuals sampled in Rio Grande do Sul state (southernmost Brazil) identified as hybrids resulting from post-F1 generations. Despite such a high level of hybridization, samples collected in this state still comprised two recognizable clusters (genetically and morphologically). Genetically pure individuals were sampled mainly in regions farther from the contact zone, while hybrids concentrated in a central region (exactly at the interface between the two biomes). The morphological data set also revealed a strong spatial structure, which was correlated with the molecular results but displayed an even more marked separation between the clusters. Hybrids often did not present intermediate body sizes and could not be clearly distinguished morphologically from the parental forms. This observation suggests that some selective pressure may be acting on the hybrids, limiting their dispersal away from the hybrid zone and perhaps favoring genomic combinations that maintain adaptive phenotypic features of one or the other parental species. [ABSTRACT FROM AUTHOR]

Conservation of small mammals requires knowledge of the genetically and ecologically meaningful spatial scales at which species respond to habitat modifications. Conservation strategies can be improved through the use of ecological niche models and genetic data to classify areas of high environmental suitability. In this study, we applied a Maxent model integrated with genetic information (nucleotide diversity, haplotype diversity and Fu's Fs neutrality tests) to evaluate potential genetic pool populations with highly suitable areas for two parapatric endangered species of tuco-tucos (Ctenomys minutus and C. lami). Our results demonstrated that both species were largely influenced by vegetation and soil variables at a landscape scale and inhabit a highly specific niche. Ctenomys minutus was also influenced by the variable altitude; the species was associated with low altitudes (sea level). Our model of genetic data associated with environmental suitability indicate that the genetic pool data were associated with highly suitable areas for C. minutus. This pattern was not evident for C. lami, but this outcome could be a consequence of the restricted range of the species. The preservation of species requires not only detailed knowledge of their natural history and genetic structure but also information on the availability of suitable areas where species can survive, and such knowledge can aid significantly in conservation planning. This finding reinforces the use of these two techniques for planning conservation actions. [ABSTRACT FROM AUTHOR]

Abstract: Studies on the spatial ecology of Molina''s hog-nosed skunk were conducted in southern Brazil. Between April 2008 and April 2009, 18 individuals were tagged with radio collars and monitored by radio-telemetry (VHF). The average home-range estimated for 12 skunks was 1.63km2 ±1.17km2. Males had home-ranges 2.5 times larger than females, and also showed significantly larger patterns of displacement. These differences in space probably were related not only to sexual size dimorphism, but also to differential behavior between sexes. We identified six basic types of resting sites, among which holes in the ground were the most common and comprised more than 50% of the total. Reuse of resting sites was high (32%), especially for females, which had a significantly higher rate than males. Although they showed a large proportion of home-range overlap even in the core areas, skunks exhibited a solitary life style, rarely sharing resting sites and maintaining relatively long distances from each other, equivalent to twice the distance of daily movements. The almost strictly nocturnal activity pattern observed in this study is a common characteristic of the family. Among practically all of the ecological features analyzed, males and females showed significant differences, denoting the importance of a sex-specific approach in ecological studies regarding this species. [Copyright &y& Elsevier]

South American tuco-tucos ( Ctenomys) are characterized by striking variation in coat colour. A range of phenotypes, from pale blonde to dark black, is observed across species, with some of them matching their local substrate colour. Moreover, phenotypic convergence is evident in some taxa that occupy similar habitats. The present study investigated a role for the melanocortin-1 receptor ( Mc1r) in determining coat-colour variation in a wide range of Ctenomys species. We sequenced 1250 bp, including the entire Mc1r coding region and a portion of the adjacent 5′ and 3′ untranslated regions, in 21 species. In total, 20 amino acid replacements were identified in Mc1r. However, our findings suggest that these changes have not contributed to coat-colour differences among tuco-tucos because no amino acid replacement was associated with pigmentation phenotype in a simple way. Levels of Mc1r expression were measured in skin samples from dorsal, flank, and ventral body regions in pale, brown, and melanic individuals. We did not observe any significant difference in transcript abundance among phenotypes, although we identified a significant reduction of expression level from the dorsal to ventral region in both pale and brown morphs but not in the completely melanic form. Thus, a role for Mc1r regulation in tuco-tucos colour pattern cannot be completely ruled out, although further functional assays are needed. Finally, selection analysis suggests that Mc1r, in a majority of lineages, has evolved under purifying selection but with relaxation in functional constraint in some regions, especially in the fourth transmembrane domain. In summary, the results obtained in the present study suggest that this trait may have a complex basis, and that other pigmentation genes are involved in generating the dramatic diversity in coat-colour phenotypes observed among Ctenomys species. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 665-680. [ABSTRACT FROM AUTHOR]

We tested the influence of migration and drift (isolation-by-distance model), and differences in micro-habitat on phenotypic traits, and correlated this with chromosomal polymorphism, at the intraspecific level, with geometric descriptors of the cranium and mandible over the entire range of subterranean rodent Ctenomys minutus. This species occurs in two different environments (dunes and sandy fields), along a strip extending for 470 km on the coastal plain of southern Brazil. Ctenomys minutus has seven parental chromosomal diploid numbers, several intraspecific hybrid zones, and up to 15 different karyotypes structured almost linearly along the coastline. Chromosomal populations show significant overall differences in size and shape, intraspecific hybrids are phenotypically intermediate between parental forms, and clustering suggests four groups delimited by chromosomal inversions and riverine barriers. Dune and field morphologies were significantly different in cranial shape. A significant but weak correlation between morphological and geographic distances along the complete distribution was found, supporting the isolation-by-distance model. The intraspecific phenotypic differences appear to arise as a combination of selection and drift acting as diversifying forces. Chromosomal inversions, rivers, and paleochannels appear to be acting as barriers to gene flow, unlike robertsonian fusions and fissions. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 705-720. [ABSTRACT FROM AUTHOR]

The tuco-tuco das dunas (Ctenomys flamarioni) is a subterranean rodent endemic to sand-dune ecosystems along the southern coast of Brazil. We studied 3 populations that differed in the degree of human impact, and used direct and indirect methods to assess demographic and genetic information. Field studies revealed a tendency toward a female-biased sex ratio, and sexual dimorphism in both weight and length in all 3 populations. This evidence supports a hypothesis of polygyny in C. flamarioni. Using 9 microsatellite loci, we explored patterns of variation and genetic structure among the populations. Our findings suggested that the Xangri-hi and Remanso populations, living in more-disturbed locations, could have experienced demographic reductions in population size, but not the Pinhal population. However, other factors such as a polygynous breeding system and the environmental instability that characterizes the coastal dunes may have influenced the observed pattern. Analysis of genetic structure revealed strong differentiation among populations, but no significant structure at the intrapopulation level, Nonsignificant values for the tested indices from assignment tests (FST, FIS, MAIc, and vAlc) over population showed no evidence of sex-biased dispersal. The same was observed from analyses of molecular variance. Nevertheless, lower pairwise FST and higher Nm values between males from Xangri-á and Remanso indicated greater gene flow among males, suggesting a slightly male-biased dispersal pattern. Significant differences in interpopulation dispersal patterns were clearer among females, with greater dispersal for females from Pinhal than those at Remanso and Xangri-lá. [ABSTRACT FROM AUTHOR]

Yellow Cardinal is an Endangered Species. Its populations are in constant decline due to habitat reduction and loss and illegal capture. There are approximately 50 free-living animals in the south of Brazil (state of Rio Grande do Sul), but estimates indicate more than 1000 in captivity. Our goals were to investigate the genetic variability of captive animals in Brazil, compare it with the genetic variability found in free-living populations, estimate the kinship of captive individuals, and obtain updated data about the number of captive animals. We found only 13% of the registered captive Yellow Cardinals. Analysis of mitochondrial sequences of captive and free-living populations was performed. We obtained 14 haplotypes, one of them (H14) exclusive of captive individuals. Furthermore, we found a haplotype exclusive to the La Pampa population in a male born in captivity in 2013. The most frequent haplotype in captive animals was the same reported for northern Argentina and Uruguay populations, which border Brazil. We found a high number of alleles by locus (mean = 9.6) for microsatellite markers, with high average heterozygosity (HO = 0.605 and HE = 0.727). The global F was 0.168. Kinship analysis of captive birds indicates a degree of kinship means of 0.082. In addition, the probability of relationship indicates that 79.4% of them are unrelated. Our data demonstrated that the captive group retains a high degree of genetic diversity with a low level of kinship. Nevertheless, the presence of haplotype exclusive for Argentina's population in captive birds, and the low level of parentage among captive animals may be representing cases of illegal wildlife trade. [ABSTRACT FROM AUTHOR]

Identifying factors that create and maintain a hybrid zone is of great interest to ecology, evolution and, more recently, conservation biology. Here, we investigated the role of environmental features in shaping the spatial dynamics of a hybrid zone between the southern tigrina, Leopardus guttulus, and Geoffroy's cat, L. geoffroyi, testing for exogenous selection as the main force acting on its maintenance. These Neotropical felid species are mainly allopatric, with a restricted area of sympatry in the ecotone between the Atlantic Forest and Pampa biomes. As both biomes have experienced high rates of anthropogenic habitat alteration, we also analysed the influence of habitat conversion on the hybrid zone structure. To do this, we used 13 microsatellite loci to identify potential hybrids and generated ecological niche models for them and their parental species. We compared the influence of variables on parental species and hybrid occurrence and calculated the amount of niche overlap among them. Parental species showed different habitat requirements and predicted co‐occurrence was restricted to the forest‐grassland mosaic of the ecotone. However, hybrids were found beyond this area, mainly in the range of L. geoffroyi. Hybrids demonstrated higher tolerance to habitat alteration than parental types, with a probability of occurrence that was positively related with mosaics of cropland areas and remnants of natural vegetation. These results indicate that exogenous selection alone does not drive the dynamics of the hybrid zone, and that habitat conversion influences its structure, potentially favouring hybrids over parental species. [ABSTRACT FROM AUTHOR]

Endemic, small range species are susceptible to environmental changes and landscape modification. Understanding genetic diversity and distributional patterns is important for implementation of effective conservation measures. In this context, genetic diversity was evaluated to update the conservation status of an endemic tuco-tuco, Ctenomys ibicuiensis. Phylogeographic and population genetic analyses of mitochondrial DNA and microsatellite loci were carried out using 46 individuals sampled across the species' distribution. Ctenomys ibicuiensis presented moderate to high genetic diversity and highly structured populations with low levels of gene flow and isolation by distance. Anthropogenic landscape changes threaten this restricted-range tuco-tuco. Considering its limited geographic distribution and highly structured populations with low gene flow, we consider C. ibicuiensis to be at significant risk of extinction. [ABSTRACT FROM AUTHOR]

We present a new assessment of the genetic and morphological variation within Oxymycterus quaestor Thomas, 1903, which currently includes the junior synonyms O. judex Thomas, 1909 and O. misionalis Sanborn, 1931. We integrate distinct lines of evidence, including variation of mitochondrial (Cytochrome b [ Cytb ]) and nuclear (intron 7 of beta fibrinogen gene [ Fgb ]) sequences, and the assessment of skull quantitative traits based on geometric morphometrics, throughout the Atlantic Forest of Southeastern-Southern Brazil, Argentina, and Paraguay. Phylogenetic relationships based on Cytb indicate that O. quaestor is structured in four well-supported clades (lineages A–D), one of them (lineage C) including topotypes of a previously associated nominal form (O. judex). However, these Cytb lineages exhibit lower levels of differentiation based on the Fgb locus, and are not recovered in the genealogies of this nuclear marker, representing a case of mitonuclear discordance. The Cytb lineages also broadly overlapped in the morphospace both in skull shape and size, which sustain the current wider concept of O. quaestor as one single young species (0.947 Myr) that is recently expanding, and ultimately branching out, in the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Knowledge of how animal species use food resources available in the environment can increase our understanding of many ecological processes. However, obtaining this information using traditional methods is difficult for species feeding on a large variety of food items in highly diverse environments. We amplified the DNA of plants for 306 scat and 40 soil samples, and applied an environmental DNA metabarcoding approach to investigate food preferences, degree of diet specialization and diet overlap of seven herbivore rodent species of the genus Ctenomys distributed in southern and midwestern Brazil. The metabarcoding approach revealed that these species consume more than 60% of the plant families recovered in soil samples, indicating generalist feeding habits of ctenomyids. The family Poaceae was the most common food resource retrieved in scats of all species as well in soil samples. Niche overlap analysis indicated high overlap in the plant families and molecular operational taxonomic units consumed, mainly among the southern species. Interspecific differences in diet composition were influenced, among other factors, by the availability of resources in the environment. In addition, our results provide support for the hypothesis that the allopatric distributions of ctenomyids allow them to exploit the same range of resources when available, possibly because of the absence of interspecific competition. [ABSTRACT FROM AUTHOR]

In contrast to the 'avian-like' diploid number (2 n = 80), most toucans and aracaris (Piciformes: Ramphastidae) have divergent karyotypes, exhibiting a higher 2 n. To identify the chromosomal rearrangements that shaped the karyotype of these species, we applied chicken macrochromosome paints 1–10 and 11 microsatellite sequences to the chromosomes of two representative species, Pteroglossus inscriptus and Ramphastos tucannus tucannus. Paints of chicken chromosomes revealed that at least the first five ancestral chromosomes have undergone fissions, and a fusion between a segment of chicken chromosome 1 and a segment from chromosome 3 occurred in both species. The microsatellite sequences were accumulated mainly in the Z chromosome and in several microchromosomes in both species. These results suggest that the genomes of the Ramphastidae have been shaped by extensive fissions and repetitive DNA accumulation as the main driving forces leading to the higher 2 n as found in these species. Furthermore, our results suggest that the putative ancestral karyotype of Ramphastidae already had a high diploid number, probably close to 2 n = 112, similar to that observed in P. inscriptus and R. t. tucannus. [ABSTRACT FROM AUTHOR]

As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (n new ) and published (n pub ) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (n pub mtDNA/microsatellite = 208/46), Brazil (n new mtDNA/microsatellite = 50/50), South Africa (n new mtDNA/microsatellite = 66/77, n pub mtDNA/microsatellite = 350/47), Chile–Peru (n new mtDNA/microsatellite = 1/1), the Indo-Pacific (n pub mtDNA/microsatellite = 769/126), and SG (n pub mtDNA/microsatellite = 8/0, n new mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile–Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American grounds. The single sample from Chile–Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile–Peru. [ABSTRACT FROM AUTHOR]

We describe a new species of the cricetid rodent Oxymycterus (Sigmodontinae), which inhabits a transitional area between the southern Cerrado and the Atlantic Forest in south-southeastern Brazil. Compared to other Oxymycterus, the new species is large-sized with a tawny-brown pelage coloration. The new species could be differentiated from other Oxymycterus species by a combination of cranial characteristics that includes markedly large and inflated auditory bulla; a narrow rostrum and large incisive foramen, with the posterior extremity reaching the posterior region of the M1 protocone or hypoflexus; a wide parapterygoid fossa; the presence of a foramen ovale in the posterior region of the parapterygoid plate; and a thin hamular process of the squamosal. Bayesian analysis based on the mitochondrial and nuclear genes (cytochrome- b and acid phosphatase type V—Intron 2, respectively) recovered from the Oxymycterus sp. nov. showed it to be phylogenetically closely related to O. amazonicus and O. delator, all three species associated with open vegetation. The lineage leading to this clade likely emerged around 1.14 million years ago during the Early-Middle Pleistocene. Genetic distances between the new taxa and these two species calculated from comparison of cytochrome- b sequences are 3.7% and 4.1%, respectively. Currently, Oxymycterus sp. nov. is known from only two unprotected sites, with the type locality inserted in an area under the process of conurbation. Our study raises the number of living species in the genus to 16. Descrevemos uma nova espécie de roedor cricetídeo Oxymycterus (Sigmodontinae), que habita uma área de transição entre o Cerrado Meridional e a Mata Atlântica no Sudeste do Brasil. Comparativamente aos demais Oxymycterus, a nova espécie possui tamanho médio e coloração marrom-avermelhada. A nova espécie também pode ser diferenciada dos demais Oxymycterus pelo tamanho e forma do crânio. Em particular por uma combinação de características cranianas, que incluem a bula auditiva acentuadamente grande e inflada, um rostro estreito e um grande forame incisivo, com a extremidade posterior alcançando a região posterior do protocone ou hipoflexus do M1; fossa parapterigóide larga; a presença de um forame oval na região posterior da placa parapteritóide; e um estreito processo hamular do esquamosal. Uma análise bayesiana reconstruída com base em genes mitocondriais e nucleares (citocromo- b e o íntron 2 do fosfatase ácida tipo V, respectivamente) demostrou que Oxymycterus sp. nov. é filogeneticamente relacionada a O. amazonicus e O. delator, todas as três espécies associadas a formações savânicas. A linhagem que deu origem a esse clado surgiu, provavelmente, há cerca de 1,14 milhão de anos (MIA) durante o Pleistoceno Médio-Antigo. A distância genética entre o novo táxon e estas duas espécies, calculadas a partir da comparação de sequências do gene citocromo- b, foram de 3.7% e 4.1%, respectivamente. Oxymycterus sp. nov. é conhecido apenas em duas localidades não protegidas, e a localidade tipo encontra-se em uma área em processo de conurbação. Nosso estudo eleva para 16 o número de espécies descritas para o gênero. [ABSTRACT FROM AUTHOR]

A major interest of evolutionary biologists is to understand which environmental features are associated with morphological and behavioural characteristics of species. Intraspecific studies addressing this question provide the best evidence for ecology-driven evolution over short time scales. Here, we evaluated whether two adjacent habitats differ in soil hardness and whether skull and forelimb morphology and estimated bite force differ between populations of a single species from sand fields and sand dunes. We used a total of 39 humeri and 88 skulls and mandibles of Ctenomys minutus from both habitats to estimate the bite force and generate morphometric data. Our results provide strong evidence that parapatric populations, occupying adjacent habitats, can respond differently in particular circumstances. This indicates that C. minutus uses different strategies (i.e. scratch-digging and tooth-digging) in the excavation of tunnels, and both of them respond to changes in soil hardness, establishing that the strategies are not evolutionarily exclusive. This difference is probably a consequence of the harder soils found in the sand fields, which are more difficult to excavate. Our results suggest the presence of divergent selection or strong phenotypic plasticity in the excavation-related morphology of populations occupying different habitats. [ABSTRACT FROM AUTHOR]

We studied the population ecology of the South American subterranean rodent Ctenomys flamarioni at the Taim Ecological Station, Rio Grande do Sul, Brazil. A capture-mark-release program was conducted in two different time periods: (A) from February 2004 to November 2005 and (B) from December 2011 to March 2013; as a result, a total of131 individuals were marked. Some population parameters remained constant (average population density, survival rate), while others fluctuated (sex ratio, estimated population size, recruitment and mortality). The second sampling period had higher estimated population size and mortality and reduced recruitment compared to the first period. Sex ratio did not differ significantly from 1:1 in period A, but showed a significant departure from 1:1 in period B, with a greater number of females captured. Ctenomys flamarioni populations seem to be substantially influenced by local environmental factors; density was positively associated with temperature and negatively associated with precipitation. This is the first report of variation through time in reproduction and population rates for this species, which is under increasing risk of extinction. [ABSTRACT FROM AUTHOR]

We describe 4 new records of Habenaria dutrae Schltr., a threatened orchid species that is endemic of Rio Grande do Sul state, Brazil. The new record, from Pontal da Barra, increases the distribution of H. dutrae by approximately 180 km south and represents the southernmost known location for the species. We also re-evaluate the conservation status of the species including the new records, finding it to be Endangered under criteria B2ab(iii); D. [ABSTRACT FROM AUTHOR]