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1.
Glob Chang Biol ; 30(3): e17180, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38465701

RESUMO

Palearctic water frogs (genus Pelophylax) are an outstanding model in ecology and evolution, being widespread, speciose, either threatened or threatening to other species through biological invasions, and capable of siring hybrid offspring that escape the rules of sexual reproduction. Despite half a century of genetic research and hundreds of publications, the diversity, systematics and biogeography of Pelophylax still remain highly confusing, in no small part due to a lack of correspondence between studies. To provide a comprehensive overview, we gathered >13,000 sequences of barcoding genes from >1700 native and introduced localities and built multigene mitochondrial (~17 kb) and nuclear (~10 kb) phylogenies. We mapped all currently recognized taxa and their phylogeographic lineages (>40) to get a grasp on taxonomic issues, cyto-nuclear discordances, the genetic makeup of hybridogenetic hybrids, and the origins of introduced populations. Competing hypotheses for the molecular calibration were evaluated through plausibility tests, implementing a new approach relying on predictions from the anuran speciation continuum. Based on our timetree, we propose a new biogeographic paradigm for the Palearctic since the Paleogene, notably by attributing a prominent role to the dynamics of the Paratethys, a vast paleo-sea that extended over most of Europe. Furthermore, our results show that distinct marsh frog lineages from Eastern Europe, the Balkans, the Near East, and Central Asia (P. ridibundus ssp.) are naturally capable of inducing hybridogenesis with pool frogs (P. lessonae). We identified 14 alien lineages (mostly of P. ridibundus) over ~20 areas of invasions, especially in Western Europe, with genetic signatures disproportionally pointing to the Balkans and Anatolia as the regions of origins, in line with exporting records of the frog leg industry and the stocks of pet sellers. Pelophylax thus emerges as one of the most invasive amphibians worldwide, and deserves much higher conservation concern than currently given by the authorities fighting biological invasions.


Assuntos
Anuros , Ranidae , Animais , Anuros/genética , Europa (Continente) , Filogenia , Filogeografia
2.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34465621

RESUMO

The genetic architecture of speciation, i.e., how intrinsic genomic incompatibilities promote reproductive isolation (RI) between diverging lineages, is one of the best-kept secrets of evolution. To directly assess whether incompatibilities arise in a limited set of large-effect speciation genes, or in a multitude of loci, we examined the geographic and genomic landscapes of introgression across the hybrid zones of 41 pairs of frog and toad lineages in the Western Palearctic region. As the divergence between lineages increases, phylogeographic transitions progressively become narrower, and larger parts of the genome resist introgression. This suggests that anuran speciation proceeds through a gradual accumulation of multiple barrier loci scattered across the genome, which ultimately deplete hybrid fitness by intrinsic postzygotic isolation, with behavioral isolation being achieved only at later stages. Moreover, these loci were disproportionately sex linked in one group (Hyla) but not in others (Rana and Bufotes), implying that large X-effects are not necessarily a rule of speciation with undifferentiated sex chromosomes. The highly polygenic nature of RI and the lack of hemizygous X/Z chromosomes could explain why the speciation clock ticks slower in amphibians compared to other vertebrates. The clock-like dynamics of speciation combined with the analytical focus on hybrid zones offer perspectives for more standardized practices of species delimitation.


Assuntos
Anuros/genética , Loci Gênicos , Especiação Genética , Animais , Genoma , Isolamento Reprodutivo
3.
Parasitology ; 150(12): 1139-1157, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37942726

RESUMO

The Mediterranean Sea is recognized as a marine biodiversity hotspot. This enclosed basin is facing several anthropogenic-driven threats, such as seawater warming, pollution, overfishing, bycatch, intense maritime transport and invasion by alien species. The present review focuses on the diversity and ecology of specific marine trophically transmitted helminth endoparasites (TTHs) of the Mediterranean ecosystems, aiming to elucidate their potential effectiveness as 'sentinels' of anthropogenic disturbances in the marine environment. The chosen TTHs comprise cestodes and nematodes sharing complex life cycles, involving organisms from coastal and marine mid/upper-trophic levels as definitive hosts. Anthropogenic disturbances directly impacting the free-living stages of the parasites and their host population demographies can significantly alter the distribution, infection levels and intraspecific genetic variability of these TTHs. Estimating these parameters in TTHs can provide valuable information to assess the stability of marine trophic food webs. Changes in the distribution of particular TTHs species can also serve as indicators of sea temperature variations in the Mediterranean Sea, as well as the bioaccumulation of pollutants. The contribution of the chosen TTHs to monitor anthropogenic-driven changes in the Mediterranean Sea, using their measurable attributes at both spatial and temporal scales, is proposed.


Assuntos
Ecossistema , Helmintos , Animais , Mar Mediterrâneo , Conservação dos Recursos Naturais , Pesqueiros
4.
J Exp Biol ; 223(Pt 21)2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32978316

RESUMO

Regulation of oxidative status plays a substantial role in physiological ageing. However, we know little about age-related changes of oxidative status in wild animals, and even less about the role of population history in moulding ageing rates. We addressed these questions by means of a common garden experiment, using the Tyrrhenian tree frog Hyla sarda as the study species. This species underwent a range expansion from northern Sardinia (source) up to Corsica (newly founded) during the Late Pleistocene, and then the two populations became geographically isolated. We found that, at the beginning of the experiment, Sardinian and Corsican frogs had similar concentrations of all oxidative status markers analysed. One year later, Corsican frogs had higher oxidative stress and suffered higher mortality than Sardinian frogs. Our results suggest the intriguing scenario that population differentiation in rates of physiological ageing owing to oxidative stress might be an overlooked legacy of past biogeographic processes.


Assuntos
Anuros , DNA Mitocondrial , Envelhecimento , Animais , Anuros/genética , França , Itália , Estresse Oxidativo
5.
Parasitology ; 146(7): 903-910, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30816081

RESUMO

Mesomycetozoean-induced infections (order Dermocystida, genus Amphibiocystidium) in European and North American amphibians are causing alarm. To date, the pathogenicity of these parasites in field conditions has been poorly studied, and demographic consequences on amphibian populations have not been explored. In this study, an Amphibiocystidium sp. infection is reported in a natural population of the Italian stream frog (Rana italica) of Central Italy, over a 7-year period from 2008 to 2014. Light and electron microscope examinations, as well as partial 18S rDNA sequence analysis were used to characterize the parasite. Moreover, a capture-mark-recapture study was conducted to assess the frog demographics in response to infection. Negative effects of amphibiocystidiosis on individual survival and population fitness were absent throughout the sampling period, despite the high estimates of disease prevalence. This might have been due to resistance and/or tolerance strategies developed by the frogs in response to the persistence of Amphibiocystidium infection in this system. We hypothesized that in the examined R. italica population, amphibiocystidiosis is an ongoing endemic/epidemic infection. However, ecological and host-specific factors, interacting in a synergistic fashion, might be responsible for variations in the susceptibility to Amphibiocystidium infection of both conspecific populations and heterospecific individuals of R. italica.


Assuntos
Infecções por Mesomycetozoea/epidemiologia , Mesomycetozoea/patogenicidade , Ranidae/parasitologia , Animais , Biópsia , Suscetibilidade a Doenças , Feminino , Interações Hospedeiro-Parasita , Itália/epidemiologia , Estudos Longitudinais , Masculino , Mesomycetozoea/genética , Prevalência , Rios/parasitologia , Pele/parasitologia , Pele/patologia
6.
Mol Ecol ; 26(20): 5663-5675, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28752635

RESUMO

Much progress in speciation research stems from documenting patterns of morphological and genetic variation in hybrid zones. Contrasting patterns of marker introgression in different sections of the contact can provide valuable insights on the relative importance of various evolutionary mechanisms maintaining species differences in the face of hybridization and gene flow and on hybrid zone temporal and spatial dynamics. We studied species interactions in the common toads Bufo bufo and B. spinosus in France and northwestern Italy using morphological and molecular data from the mitochondrial and nuclear genomes in an extensive survey, including two independent transects west and east of the Alps. At both, we found sharp, coincident and concordant nuclear genetic transitions. However, morphological clines were wider or absent and mtDNA introgression was asymmetric. We discuss alternative, nonexclusive hypotheses about evolutionary processes generating these patterns, including drift, selection, long-distance dispersal and spatial shifts in hybrid zone location and structure. The distribution of intraspecific mtDNA lineages supports a scenario in which B. bufo held a local refugium during the last glacial maximum. Present-day genetic profiles are best explained by an advance of B. spinosus from a nearby Iberian refugium, largely superseding the local B. bufo population, followed by an advance of B. bufo from the Balkans, with prongs north and south of the Alps, driving B. spinosus southwards. A pendulum moving hybrid zone, first northwards and then southwards, explains the wide areas of introgression at either side of the current position of the contact zones.


Assuntos
Bufo bufo/classificação , Bufonidae/classificação , Fluxo Gênico , Especiação Genética , Genética Populacional , Hibridização Genética , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , França , Deriva Genética , Itália , Seleção Genética
7.
Mol Phylogenet Evol ; 83: 143-55, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25482363

RESUMO

European tree frogs (Hyla) characterized by short temporal parameters of the advertisement call form six genetically differentiated but morphologically cryptic taxa, H. arborea sensu stricto, H. orientalis and H. molleri from across Europe to western Asia (together referred to as H. arborea sensu lato), two putative taxa within H. intermedia (Northern and Southern) from the Italian Peninsula and Sicily, and H. sarda from Sardinia and Corsica. Here, we assess species limits and phylogenetic relationships within these 'short-call tree frogs' based on mitochondrial DNA and nuclear protein-coding markers. The mitochondrial and nuclear genes show partly incongruent phylogeographic patterns, which point to a complex history of gene flow across taxa, particularly in the Balkans. To test the species limits in the short-call tree frogs and to infer the species tree, we used coalescent-based approaches. The monophyly of H. arborea sensu lato is supported by the mtDNA as well as by the all-gene species tree. The Northern and Southern lineages of H. intermedia have been connected by nuclear gene flow (despite their deep mtDNA divergence) and should be treated as conspecific. On the contrary, the parapatric taxa within H. arborea sensu lato should be considered distinct species (H. arborea, H. orientalis, H. molleri) based on the coalescent analysis, although signs of hybridization were detected between them (H. arborea×H. orientalis; H. arborea×H. molleri). A mitochondrial capture upon secondary contact appears to explain the close mtDNA relationship between the geographically remote Iberian H. molleri and H. orientalis from around the Black Sea. Introgressive hybridization occurred also between the Balkan H. arborea and northern Italian H. intermedia, and between the Minor Asiatic H. orientalis and Arabian H. felix arabica (the latter belonging to a different acoustic group/clade). Our results shed light on the species limits in the European short-call tree frogs and show that introgression played an important role in the evolutionary history of the short-call tree frogs and occurred even between taxa supported as distinct species.


Assuntos
Anuros/classificação , Evolução Biológica , Especiação Genética , Filogenia , Animais , Anuros/genética , Ásia Ocidental , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Europa (Continente) , Fluxo Gênico , Haplótipos , Modelos Genéticos , Filogeografia , Análise de Sequência de DNA
8.
Sci Rep ; 14(1): 892, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195624

RESUMO

Sexual dimorphism is almost ubiquitous in animals. A common pattern observed across multiple taxa involves differences in development time (sexual bimaturism) and body size (sexual size dimorphism) between conspecific males and females. Furthermore, a strict association of dimorphism at these traits has been documented in several taxa, where the sex showing shorter development time also has a smaller body size than the other sex. Growth and development are strongly dependent on environmental conditions during individual life-cycle in ectotherms, inducing considerable phenotypic plasticity. However, how phenotypic plasticity affects the association between sexual dimorphism in development time and body size remains unclear. Here, we tracked development time, body size, and body mass throughout the ontogeny of the mosquito Aedes mariae. The larval development of this species is strictly linked to Mediterranean Sea rock-pools, whose highly variable environmental conditions over minimal time frames make this organism-environment system ideal for exploring plasticity-led eco-evolutionary processes. We found differential plasticity between males and females, dissolving the link between dimorphism in development time and body size under increasing temperature and decreasing salinity conditions. These findings contrast with the current hypotheses proposed to explain the origin of the association between sexual bimaturism and sexual size dimorphism, highlighting the condition dependence of sexual dimorphism patterns and the need to consider phenotypic plasticity in future studies on their evolution.


Assuntos
Culicidae , Caracteres Sexuais , Animais , Feminino , Masculino , Tamanho Corporal , Adaptação Fisiológica , Mar Mediterrâneo
9.
Sci Total Environ ; 942: 173626, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38844229

RESUMO

Organic farming is considered the most sustainable form of modern soil cultivation. Yet it often relies on the use of chemical compounds that are not necessarily harmless for the surrounding wildlife. In this study, we tested the effects of realistic concentrations of copper sulphate-largely used in organic farming as a fungicide-on ecologically-relevant traits of the walking stick insect Bacillus rossius, a species commonly found in the proximity of cultivated fields across Europe. By using second-generation progeny of wild-caught parthenogenetic females bred in common gardens, we measured the impact of copper sulphate (CuSO4) on both the life-history (body condition, number of eggs, and hatching success) and behavioural traits (activity and maximum vertical speed) of the individuals. We observed strong negative effects of high, realistic concentrations of copper sulphate on most traits within 12 days of exposure, while effects were less evident at lower concentrations of the pollutant. Our results reveal that realistic concentrations of copper sulphate can compromise important traits that regulate both the survival and reproduction of animals in the wild, with such effects that are, however, dose dependent. We suggest that common practices in organic farming require further consideration on their ecological and evolutionary impact on wildlife.


Assuntos
Sulfato de Cobre , Agricultura Orgânica , Animais , Sulfato de Cobre/toxicidade , Feminino , Poluentes do Solo/toxicidade , Fungicidas Industriais/toxicidade , Insetos/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Neópteros/fisiologia , Neópteros/efeitos dos fármacos
10.
Mol Ecol ; 22(1): 143-56, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23163335

RESUMO

Islands are hotspots of biodiversity, with a disproportionately high fraction of endemic lineages, often of ancient origin. Nevertheless, intra-island phylogeographies are surprisingly scarce, leading to a scanty knowledge about the microevolutionary processes induced on island populations by Plio-Pleistocene climatic oscillations, and the manner in which these processes contributed to shape their current genetic diversity. We investigated the phylogeography, historical demography and species distribution models of the Corsican endemic newt Euproctus montanus (north-western Mediterranean). As for many island endemics, the continuous distribution of E. montanus throughout its range has hitherto been considered as evidence for a single large population, a belief that also guided the species' categorization for conservation purposes. Instead, we found a geographic mosaic of ancient evolutionary lineages, with five main clades of likely Pliocene origin (2.6-5.8 My), all but one restricted to northern Corsica. Moreover, the copresence between main lineages in the same population was limited to a single case. As also suggested by growing literature on intra-island phylogeographic variation, it seems that the extensive use of simplifying assumption on the population structure and historical demography of island populations--both in theoretical and applicative studies--should be carefully reconsidered, a claim that is well exemplified by the case presented here.


Assuntos
Evolução Biológica , Genética Populacional , Filogenia , Salamandridae/genética , Animais , Conservação dos Recursos Naturais , França , Geografia , Ilhas , Modelos Biológicos , Filogeografia , Dinâmica Populacional , Salamandridae/classificação
11.
Mol Phylogenet Evol ; 69(3): 1203-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23880535

RESUMO

Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like ecology and conservation biology. We here review molecular genetic evidence relevant to the systematics of toads in the Bufo bufo species group (Anura, Bufonidae). Two studies recently published in this journal (Recuero et al., MPE 62: 71-86 and García-Porta et al., MPE 63: 113-130) addressed this issue but reached opposing conclusions on the taxonomy of the group (four versus two species). In particular, allozyme data in the latter paper were interpreted as evidence for hybridization across species (between B. bufo-B. spinosus and B. bufo-B. verrucosissimus). We tested claims for hybridization through re-analysis of allozyme data for individuals instead of populations, to be able to distinguish between sympatry with and without admixture, and found no evidence of hybridization across taxa. We propose alternative explanations for the observed patterns that García-Porta et al. (2012) failed to consider. In the absence of unequivocal evidence for hybridization and introgression, we reject the proposal to downgrade Bufo spinosus and Bufo verrucosissimus to the subspecies level.


Assuntos
Bufonidae/classificação , Evolução Molecular , Hibridização Genética , Filogenia , Animais , Teorema de Bayes , Bufonidae/genética , Europa (Continente) , Especiação Genética , Genética Populacional , Isoenzimas/genética , Análise de Sequência de DNA , Simpatria
12.
Dis Aquat Organ ; 107(1): 61-8, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-24270024

RESUMO

The amphibian chytrid pathogen Batrachochytrium dendrobatidis (Bd) is considered a major cause of amphibian population declines, particularly in montane areas. Here, we investigated the presence and distribution of Bd among populations of 3 mid- to high-altitude species spanning the entire Italian peninsula (486 individuals from 39 sites overall): the stream frog Rana italica, the fire salamander Salamandra salamandra gigliolii, and the alpine newt Mesotriton alpestris apuanus. We found Bd in all of the analyzed species. Despite the widespread distribution of the pathogen, its overall prevalence (6, 9 and 19%, respectively) was lower than previously reported for the endangered Apennine yellow-bellied toad Bombina pachypus (62.5%). Moreover, several populations of the species studied here were not infected, even at sites where Bd has been detected in other host species. When coupled with the lack of evidence for Bd-related mortalities in these species in peninsular Italy, these results suggest that mechanisms of resistance and/or tolerance are protecting populations of these species from the pathogenic activity of Bd. Nevertheless, in light of the dynamic pattern of Bd-host interactions reported in other studies, of Bd-related mortalities in at least 1 study species (S. s. salamandra) in other areas, and the ongoing climate changes in montane environments, we suggest that the occurrence of Bd should be considered a potential threat to the long-term persistence of these species, and urge the implementation of monitoring and conservation plans.


Assuntos
Altitude , Anfíbios/classificação , Quitridiomicetos/isolamento & purificação , Micoses/veterinária , Anfíbios/fisiologia , Animais , Demografia , Itália/epidemiologia , Micoses/epidemiologia , Micoses/microbiologia
13.
Trends Ecol Evol ; 38(11): 1097-1108, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37620217

RESUMO

Hybridization as an evolutionary process has been studied in depth over the past few decades. Research has focused on its role in shaping reproductive barriers, its adaptive value, and its genomic consequences. In contrast, our knowledge of ecological dimensions of hybridization is still in its infancy, despite hybridization being an inherently ecological interaction. Using examples from various organisms, we show that hybridization can affect and be affected by non-reproductive interactions, including predation, competition, parasitism, mutualism, commensalism, and organism-environment interactions, with significant implications for community structure and ecosystem functioning. However, since these dimensions of hybridization have mostly been revealed from studies designed to decipher other evolutionary processes, we argue that much of the eco-evolutionary importance of hybridization is yet to be discovered.

14.
Curr Zool ; 69(5): 631-641, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37637312

RESUMO

Recent empirical and theoretical studies suggest that personality and locomotory performance traits linked to dispersal abilities are crucial components of the dispersal syndromes, and that they can evolve during range expansions and colonization processes. Island colonization is one of the best characterized processes in dispersal biogeography, and its implication in the evolution of phenotypic traits has been investigated over a wide range of temporal scales. However, the effect of island colonization on personality and performance traits of natural populations, and how these traits could drive island colonization, has been little explored. Noteworthy, no studies have addressed these processes in the context of late Pleistocene range expansions. Here, we investigated the contribution of island colonization triggered by postglacial range expansions to intraspecific variation in personality and locomotory performance traits. We compared boldness, exploration, jumping performance, and stickiness abilities in populations from 3 equidistant areas of the Tyrrhenian tree frog Hyla sarda, 2 from the main island (Corsica Island), and 1 from the recently colonized island of Elba. Individuals from Elba were significantly bolder than individuals from Corsica, as they emerged sooner from a shelter (P = 0.028), while individuals from Corsica showed markedly higher jumping and stickiness performance (both P < 0.001), resulting as more performing than those of Elba. We discuss these results in the context of the major microevolutionary processes at play during range expansion, including selection, spatial sorting, founder effects, and their possible interaction with local adaptation processes.

15.
Sci Data ; 10(1): 330, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37244908

RESUMO

Dispersal is a key process in ecology and evolutionary biology, as it shapes biodiversity patterns over space and time. Attitude to disperse is unevenly distributed among individuals within populations, and that individual personality can have pivotal roles in the shaping of this attitude. Here, we assembled and annotated the first de novo transcriptome of the head tissues of Salamandra salamandra from individuals, representative of distinct behavioral profiles. We obtained 1,153,432,918 reads, which were successfully assembled and annotated. The high-quality of the assembly was confirmed by three assembly validators. The alignment of contigs against the de novo transcriptome led to a mapping percentage higher than 94%. The homology annotation with DIAMOND led to 153,048 (blastx) and 95,942 (blastp) shared contigs, annotated on NR, Swiss-Prot and TrEMBL. The domain and site protein prediction led to 9850 GO-annotated contigs. This de novo transcriptome represents reliable reference for comparative gene expression studies between alternative behavioral types, for comparative gene expression studies within Salamandra, and for whole transcriptome and proteome studies in amphibians.


Assuntos
Salamandra , Transcriptoma , Animais , Perfilação da Expressão Gênica , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Larva/genética , Anotação de Sequência Molecular , Salamandra/genética
16.
Sci Data ; 10(1): 720, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857654

RESUMO

Understanding the genomic underpinnings of thermal adaptation is a hot topic in eco-evolutionary studies of parasites. Marine heteroxenous parasites have complex life cycles encompassing a free-living larval stage, an ectothermic intermediate host and a homeothermic definitive host, thus representing compelling systems for the study of thermal adaptation. The Antarctic anisakid Contracaecum osculatum sp. D is a marine parasite able to survive and thrive both at very cold and warm temperatures within the environment and its hosts. Here, a de novo transcriptome of C. osculatum sp. D was generated for the first time, by performing RNA-Seq experiments on a set of individuals exposed to temperatures experienced by the nematode during its life cycle. The analysis generated 425,954,724 reads, which were assembled and then annotated. The high-quality assembly was validated, achieving over 88% mapping against the transcriptome. The transcriptome of this parasite will represent a valuable genomic resource for future studies aimed at disentangling the genomic architecture of thermal tolerance and metabolic pathways related to temperature stress.


Assuntos
Nematoides , Parasitos , Animais , Humanos , Regiões Antárticas , Nematoides/genética , Temperatura , Transcriptoma
17.
Sci Data ; 9(1): 619, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229462

RESUMO

Understanding the genomic underpinnings of antipredatory behaviors is a hot topic in eco-evolutionary research. Yellow-bellied toad of the genus Bombina are textbook examples of the deimatic display, a time-structured behavior aimed at startling predators. Here, we generated the first de novo brain transcriptome of the Apennine yellow-bellied toad Bombina pachypus, a species showing inter-individual variation in the deimatic display. Through Rna-Seq experiments on a set of individuals showing distinct behavioral phenotypes, we generated 316,329,573 reads, which were assembled and annotated. The high-quality assembly was confirmed by assembly validators and by aligning the contigs against the de novo transcriptome with a mapping percentage higher than 91.0%. The homology annotation with DIAMOND (blastx) led to 77,391 contigs annotated on Nr, Swiss Prot and TrEMBL, whereas the domain and site protein prediction made with InterProScan led to 4747 GO-annotated and 1025 KEGG-annotated contigs. The B. pachypus transcriptome described here will be a valuable resource for further studies on the genomic underpinnings of behavioral variation in amphibians.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Transcriptoma , Animais , Anuros , Encéfalo , Anotação de Sequência Molecular , Análise de Sequência de RNA
18.
Evol Appl ; 15(9): 1344-1359, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36187190

RESUMO

Assigning individuals to their source populations is crucial for conservation research, especially for endangered species threatened by illegal trade and translocations. Genetic assignment can be achieved with different types of molecular markers, but technical advantages and cost saving are recently promoting the shift from short tandem repeats (STRs) to single nucleotide polymorphisms (SNPs). Here, we designed, developed, and tested a small panel of SNPs for cost-effective geographic assignment of individuals with unknown origin of the endangered Mediterranean tortoise Testudo hermanni. We started by performing a ddRAD-seq experiment on 70 wild individuals of T. hermanni from 38 locations. Results obtained using 3182 SNPs are comparable to those previously obtained using STR markers in terms of genetic structure and power to identify the macro-area of origin. However, our SNPs revealed further insights into the substructure in Western populations, especially in Southern Italy. A small panel of highly informative SNPs was then selected and tested by genotyping 190 individuals using the KASP genotyping chemistry. All the samples from wild populations of known geographic origin were genetically re-assigned with high accuracy to the original population. This reduced SNPs panel represents an efficient molecular tool that enables individuals to be genotyped at low cost (less than €15 per sample) for geographical assignment and identification of hybrids. This information is crucial for the management in-situ of confiscated animals and their possible re-allocation in the wild. Our methodological pipeline can easily be extended to other species.

19.
BMC Ecol Evol ; 22(1): 131, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344915

RESUMO

BACKGROUND: Hotspots of intraspecific genetic diversity represent invaluable resources for species to cope with environmental changes, and their identification is increasingly recognized as a major goal of conservation ecology research. However, even for iconic and endangered species, conservation strategies are often planned without thorough information on the geographic patterns of genetic variation. Here, we investigated the spatial patterns of genetic variation of the endangered Hermann's tortoise Testudo hermanni in the Italian Peninsula by genotyping 174 individuals at 7 microsatellite loci, with the aim to contribute to planning effective conservation strategies. RESULTS: Ordination-based and Bayesian clustering analyses consistently identified three main genetic clusters, one spread in the central and northern part of the peninsula, and two restricted to southern Italy and Sicily, respectively. The highest levels of genetic diversity were found in populations of the southern cluster and, in particular, at the northern edges of its distribution (He > 0.6, Ar > 2.8 ), that correspond to areas of putative secondary contact and admixture between distinct lineages. Our results clearly identify a hotspot of genetic diversity for the Hermann's tortoise in southern Italy. CONCLUSION: We inferred the evolutionary history and the spatial patterns of genetic variation of the Hermann's tortoise in the Italian Peninsula. We identified three main genetic clusters along the peninsula and a hotspot of intraspecific diversity in southern Italy. Our results underline the urgent need for conservation actions to warrant the long-term persistence of viable tortoise populations in this area. Furthrmore, these data add further evidence to the role of southern Italy as a biodiversity hotspot for temperate fauna, claiming for higher consideration of this area in large scale conservation programs.


Assuntos
Tartarugas , Humanos , Masculino , Animais , Tartarugas/genética , Teorema de Bayes , Repetições de Microssatélites/genética , Variação Genética/genética , Sicília
20.
Mol Ecol ; 20(24): 5313-27, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22097966

RESUMO

Many temperate species experienced demographic and range contractions in response to climatic changes during Pleistocene glaciations. In this study, we investigate the evolutionary history of the Tyrrhenian tree frog Hyla sarda, a species inhabiting the Corsica-Sardinia island system (Western Mediterranean basin). We used sequence analysis of two mitochondrial (overall 1229 bp) and three nuclear (overall 1692 bp) gene fragments to assess the phylogeography and demographic history of this species, and species distribution modelling (SDM) to predict its range variation over time. Phylogeographic, historical demographic and SDM analyses consistently indicate that H. sarda does not conform to the scenario generally expected for temperate species but rather underwent demographic and range expansion mostly during the last glacial phase. Palaeogeographic data and SDM analyses suggest that such expansion was driven by the glaciation-induced increase in lowland areas during marine regression. This unusual scenario suggests that at least some temperate species may not have suffered the adverse effects of glacial climate on their population size and range extent, owing to the mitigating effects of other glaciations-induced palaeoenvironmental changes. We discuss previous clues for the occurrence of such a scenario in other species and some possible challenges with its identification. Early phylogeographic literature suggested that responses to the Pleistocene glacial-interglacial cycles were expected to vary among species and regions. Our results point out that such variation may have been greater than previously thought.


Assuntos
Evolução Biológica , Ranidae/classificação , Ranidae/genética , Animais , Clima , DNA Mitocondrial/genética , Bases de Dados Genéticas , França , Variação Genética , Geografia , Haplótipos , Itália , Filogeografia , Densidade Demográfica , Análise de Sequência de DNA
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