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1.
Ecol Appl ; 34(4): e2980, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38725332

RESUMO

Understanding how human-modified landscapes maintain biodiversity and provide ecosystem services is crucial for establishing conservation practices. Given that responses to land-use are species-specific, it is crucial to understand how land-use changes may shape patterns of species diversity and persistence in human-modified landscapes. Here, we used a comprehensive data set on bird distribution from the Brazilian Atlantic Forest to understand how species richness and individual occurrences of frugivorous bird species responded to land-use spatial predictors and, subsequently, assess how ecological traits and phylogeny modulated these responses. Using Bayesian hierarchical modeling, we reveal that the richness of frugivorous birds was positively associated with the amount of native forest and negatively with both agriculture and pasture amount at the landscape scale. Conversely, the effect of these predictors on species occurrence and ecological traits was highly variable and presented a weak phylogenetic signal. Furthermore, land-use homogenization (i.e., the conversion of forest to pasture or agriculture) led to pervasive consequences for forest-dependent bird species, whereas several generalist species thrived in deforested areas, replacing those sensitive to habitat disturbances.


Assuntos
Agricultura , Biodiversidade , Aves , Animais , Aves/fisiologia , Brasil , Clima Tropical , Conservação dos Recursos Naturais/métodos , Florestas , Frutas
2.
Conserv Biol ; 38(5): e14351, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248759

RESUMO

Unsustainable wildlife consumption and illegal wildlife trade (IWT) threaten biodiversity worldwide. Although publicly accessible data sets are increasingly used to generate insights into IWT, little is known about their potential bias. We compared three typical and temporally corresponding data sets (4204 court verdicts, 926 seizure news reports, and 219 bird market surveys) on traded birds native to China and evaluated their possible species biases. Specifically, we evaluated bias and completeness of sampling for species richness, phylogeny, conservation status, spatial distribution, and life-history characteristics among the three data sets when determining patterns of illegal trade. Court verdicts contained the largest species richness. In bird market surveys and seizure news reports, phylogenetic clustering was greater than that in court verdicts, where songbird species (i.e., Passeriformes) were detected in higher proportions in market surveys. The seizure news data set contained the highest proportion of species of high conservation priority but the lowest species coverage. Across the country, all data sets consistently reported relatively high species richness in south and southwest regions, but markets revealed a northern geographic bias. The species composition in court verdicts and markets also exhibited distinct geographical patterns. There was significant ecological trait bias when we modeled whether a bird species is traded in the market. Our regression model suggested that species with small body masses, large geographical ranges, and a preference for anthropogenic habitats and those that are not nationally protected were more likely to be traded illegally. The species biases we found emphasize the need to know the constraints of each data set so that they can optimally inform strategies to combat IWT.


Cuantificación del sesgo por especies entre fuentes de datos múltiples para el mercado ilegal de fauna y lo que implica para la conservación Resumen El consumo insostenible y el comercio ilegal de fauna y flora silvestres amenazan la biodiversidad en todo el mundo. Aunque los conjuntos de datos de acceso público se utilizan cada vez más para obtener información sobre el mercado ilegal de especies silvestres, se sabe poco sobre su posible sesgo. Comparamos tres conjuntos de datos típicos con correspondencia temporal (4,204 sentencias judiciales, 926 informes de noticias sobre incautaciones y 219 encuestas sobre mercados de aves) de aves autóctonas de China objeto de comercio y evaluamos sus posibles sesgos por especie. En concreto, evaluamos el sesgo y la exhaustividad del muestreo de la riqueza de especies, la filogenia, el estado de conservación, la distribución espacial y las características del ciclo vital entre los tres conjuntos de datos a la hora de determinar los patrones del mercado ilegal. Las sentencias judiciales contenían la mayor riqueza de especies. En los estudios de mercado de aves y en los informes de noticias sobre incautaciones, la agrupación filogenética fue mayor que en las sentencias judiciales, donde las especies de aves canoras (Passeriformes) se detectaron en mayor proporción en los estudios de mercado. El conjunto de datos de noticias sobre decomisos contenía la mayor proporción de especies de alta prioridad para la conservación, pero la menor cobertura de especies. En todo el país, todos los conjuntos de datos informaron sistemáticamente de una riqueza de especies relativamente alta en las regiones sur y suroeste, pero los mercados revelaron un sesgo geográfico septentrional. La composición por especies en los veredictos judiciales y en los mercados también mostró patrones geográficos distintos. Hubo un sesgo significativo de rasgos ecológicos cuando modelamos si una especie de ave se comercializa en el mercado. Nuestro modelo de regresión sugería que las especies con masas corporales pequeñas, grandes áreas de distribución geográfica y preferencia por los hábitats antropogénicos y las especies que no están protegidas a nivel nacional tenían más probabilidades de ser objeto de comercio ilegal. Los sesgos de las especies que hallamos resaltan la necesidad de conocer las limitaciones de cada conjunto de datos para poder informar de manera óptima las estrategias de lucha contra el comercio ilegal de especies silvestres.


Assuntos
Biodiversidade , Aves , Comércio , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/legislação & jurisprudência , Animais , China , Comércio/legislação & jurisprudência , Crime/estatística & dados numéricos , Animais Selvagens , Filogenia , Comércio de Vida Silvestre
3.
Mol Ecol ; 32(1): 214-228, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36261866

RESUMO

Although vicariant processes are expected to leave similar genomic signatures among codistributed taxa, ecological traits such as habitat and stratum can influence genetic divergence within species. Here, we combined landscape history and habitat specialization to understand the historical and ecological factors responsible for current levels of genetic divergence in three species of birds specialized in seasonally flooded habitats in muddy rivers and which are widespread in the Amazon basin but have isolated populations in the Rio Branco. Populations of the white-bellied spinetail (Mazaria propinqua), lesser wagtail-tyrant (Stigmatura napensis) and bicolored conebill (Conirostrum bicolor) are currently isolated in the Rio Branco by the black-waters of the lower Rio Negro, offering a unique opportunity to test the effect of river colour as a barrier to gene flow. We used ultraconserved elements (UCEs) to test alternative hypotheses of population history in a comparative phylogeographical approach by modelling genetic structure, demographic history and testing for shared divergence time among codistributed taxa. Our analyses revealed that (i) all three populations from the Rio Branco floodplains are genetically distinct from other populations along the Amazon River floodplains; (ii) these divergences are the result of at least two distinct events, consistent with species habitat specialization; and (iii) the most likely model of population evolution includes lower population connectivity during the Late Pleistocene transition (~250,000 years ago), with gene flow being completely disrupted after the Last Glacial Maximum (~21,000 years ago). Our findings highlight how landscape evolution modulates population connectivity in habitat specialist species and how organisms can have different responses to the same historical processes of environmental change, depending on their habitat affinity.


Assuntos
Variação Genética , Metagenômica , Animais , Ecossistema , Filogeografia , Aves/genética , Filogenia , DNA Mitocondrial/genética
4.
Theor Popul Biol ; 153: 102-110, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37442528

RESUMO

Dispersal can enable access to resources in new locations. Consequently, traits that govern dispersal probability and dispersal distance may impact an individual's ability to acquire resources. However, spatial variation in the quality or quantity of resources may mediate potential adaptive benefits of novel dispersal traits. Ecological traits (i.e., those that determine how an individual processes resources) will also, by definition, affect how an individual interacts with the resource landscape. In a spatially heterogeneous environment, this creates potential for evolutionary feedbacks between dispersal-related traits and ecological traits. For example, dispersal may introduce individuals to novel resources, at which point there may be selection for local adaptation of ecological traits. Conversely, an individual's ability to utilize different resource types may determine how dispersal impacts fitness. Here, we develop an individual-based model to investigate co-evolution of dispersal and ecological traits in a landscape where multiple resources vary independently across space. We find that: (1) resource specialists can emerge and tend to evolve dispersal strategies suited to the structure of their preferred resource type and (2) generalists, when they emerge, tend to possess intermediate dispersal strategies. Lastly, we note that the effect of dispersal on the evolution of the ecological trait is weaker than vice versa and, as a result, appreciable heterogeneity in the abundance of resources across a landscape will likely obscure a signal of co-evolution.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Humanos , Dinâmica Populacional , Fenótipo , Ecossistema
5.
J Anim Ecol ; 92(2): 352-366, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36385373

RESUMO

Performance trade-offs between competition and colonization can be an important mechanism facilitating regional coexistence of competitors. However, empirical evidence for this trade-off is mixed, raising questions about the extent to which it shapes diverse ecological communities. Here, we outline a framework that can be used to improve empirical tests of the competition-colonization trade-off. We argue that tests of the competition-colonization trade-off have been diverted into unproductive paths when dispersal mode and/or competition type have been inadequately defined. To generate comparative predictions of associations between dispersal and competitive performance, we develop a conceptual trait-based framework that clarifies how dispersal mode and type of competitor shape this trade-off at the stage of dispersal and establishment in a variety of systems. Our framework suggests that competition-colonization trade-offs may be less common for passively dispersing organisms when competitive dominants are those best able to withstand resource depletion (competitive response), and for active dispersers when traits for dispersal performance are positively associated with resource pre-emption (competitive effect). The framework presented here is designed to provide common ground for researchers working in different systems in order to prompt more effective assessment of this performance trade-off and its role in shaping community structure. By delineating key system properties that mediate the trade-off between competitive and colonization performance and their relationship to individual-level traits, researchers in disparate systems can structure their predictions about this trade-off more effectively and compare across systems more clearly.


Assuntos
Biota , Ecossistema , Animais , Fenótipo , Modelos Biológicos
6.
Naturwissenschaften ; 110(6): 54, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37957333

RESUMO

The current ecological crisis has risen extinction rates to similar levels of ancient mass extinctions. However, it seems to not be acting uniformly across all species but affecting species differentially. This suggests that species' susceptibility to the extinction process is mediated by specific traits. Since understanding this response mechanism at large scales will benefit conservation effort around the world, we used the IUCN global threat status and population trends of 8281 extant bird species as proxies of the extinction risk to identify the species-specific traits affecting their susceptibility to extinction within the biogeographic regions and at the global scale. Using linear mixed effect models and multinomial models, we related the global threat status and the population trends with the following traits: migratory strategy, habitat and diet specialization, body size, and generation length. According to our results and independently of the proxy used, more vulnerable species are sedentary and have larger body size, longer generation time, and higher degree of habitat specialization. These relationships apply globally and show little variation across biogeographic regions. We suggest that such concordant patterns might be caused either by a widespread occurrence of the same threats such as habitat modification or by a uniform capacity of some traits to reflect the impact of different local threats. Regardless of the cause of this pattern, our study identified the traits that affect species' response capability to the current ecological crisis. Conservation effort should focus on the species with trait values indicating the limited response capacity to overcome this crisis.


Assuntos
Mudança Climática , Extinção Biológica , Animais , Ecossistema , Especificidade da Espécie , Aves , Conservação dos Recursos Naturais , Biodiversidade
7.
Glob Chang Biol ; 28(3): 1077-1090, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34783130

RESUMO

Invasive alien species (IAS) are a major threat to insular vertebrates, although the ecological characteristics that make insular communities vulnerable to IAS are poorly understood. After describing the ecological strategies of 6015 insular amphibians, birds, lizards, and mammals, we assessed the functional and ecological features of vertebrates exposed to IAS. We found that at least 50% of insular amphibian functional richness was hosted by IAS-threatened amphibians and up to 29% for birds. Moreover, all IAS-threatened groups except birds harbored a higher functional richness than species groups threatened by other threats. Disentangling the ecological strategies threatened by IAS, compared to those associated with other threats, we showed that birds, lizards, and mammals were more likely to be terrestrial foragers and amphibians to have larval development. By contrast, large-bodied species and habitat specialists were universally threatened. By considering the functional aspect of threatened insular diversity, our work improves our understanding of global IAS impacts. This new dimension proves essential for undertaking relevant and effective conservation actions.


Assuntos
Espécies em Perigo de Extinção , Extinção Biológica , Anfíbios , Animais , Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Vertebrados
8.
J Fish Biol ; 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36571395

RESUMO

Phylogeographic congruence among co-distributed taxa is regarded as an inherent inference to vicariance events. Nonetheless, incongruent patterns of contemporary lineage divergence among taxa indicated that species differ in their response to common past events. To investigate the role of past events, ecological traits and lineage diversification time in shaping the contemporary phylogeographic patterns, comparative analyses were conducted for Tibetan stone loaches in the Himalayas using three gene markers and two ecological traits (depth of caudal peduncle in their length and presence/absence of posterior chamber of the air bladder). By a thorough sampling in two flanks of the Himalayas, the authors detected that phylogenetic breaks were spatially discordant and divergences of populations were also temporally asynchronous in co-distributed loaches. Estimated divergence time using fossil-calibrated node dating indicated that the Tibetan stone loaches colonised into the south flank of the Himalayas until the Pleistocene. The demographic expansions were also disconcerted between populations in north and south flanks, or east and west Himalayas. Ongoing gene flows between populations in north and south sides implied that the Himalayas do not strictly impede dispersal of cold-adapted species. The results highlight that the quaternary climatic oscillation, in conjunction with ecological traits and lineage diversification time, shaped contemporary phylogenetic patterns of stone loaches in the Himalayas and provide new insights into the biodiversity and composition of species in the Himalayas and surrounding region.

9.
Proc Biol Sci ; 288(1963): 20211651, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34784766

RESUMO

Back and forth transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between humans and animals will establish wild reservoirs of virus that endanger long-term efforts to control COVID-19 in people and to protect vulnerable animal populations. Better targeting surveillance and laboratory experiments to validate zoonotic potential requires predicting high-risk host species. A major bottleneck to this effort is the few species with available sequences for angiotensin-converting enzyme 2 receptor, a key receptor required for viral cell entry. We overcome this bottleneck by combining species' ecological and biological traits with three-dimensional modelling of host-virus protein-protein interactions using machine learning. This approach enables predictions about the zoonotic capacity of SARS-CoV-2 for greater than 5000 mammals-an order of magnitude more species than previously possible. Our predictions are strongly corroborated by in vivo studies. The predicted zoonotic capacity and proximity to humans suggest enhanced transmission risk from several common mammals, and priority areas of geographic overlap between these species and global COVID-19 hotspots. With molecular data available for only a small fraction of potential animal hosts, linking data across biological scales offers a conceptual advance that may expand our predictive modelling capacity for zoonotic viruses with similarly unknown host ranges.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Especificidade de Hospedeiro , Humanos , Mamíferos , Glicoproteína da Espícula de Coronavírus
10.
Mol Ecol ; 30(16): 4062-4076, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34160853

RESUMO

Understanding how geographic and environmental heterogeneity drive local patterns of genetic variation is a major goal of ecological genomics and a key question in evolutionary biology. The tropical Andes and inter-Andean valleys are shaped by markedly heterogeneous landscapes, where species experience strong selective processes. We examined genome-wide SNP data together with behavioural and ecological traits (mating calls and body size) known to contribute to genetic isolation in anurans in the banana tree-dwelling frog, Boana platanera, distributed across an environmental gradient in Central Colombia (northern South America). Here, we analysed the relationships between environmentally (temperature and precipitation) associated genetic and phenotypic differentiation and the potential drivers of isolation by environment along an elevation gradient. We identified candidate SNPs associated with temperature and body size, which follow a clinal pattern of genome-wide differentiation tightly coupled with phenotypic variation: as elevation increases, B. platanera exhibits larger body size and longer call duration with more pulses but lower pulse rate and frequency. Thus, the environmental landscape has rendered a scenario where isolation by environment and candidate loci show concordance with phenotypic divergence in this tropical frog along an elevation gradient in the Colombian Andes. Our study sets the basis for evaluating the role of temperature in the genetic structure and local adaptation in tropical treefrogs and its putative effect on life cycle (embryos, tadpoles, adults) along elevation gradients.


Assuntos
Altitude , Anuros , Animais , Anuros/genética , Colômbia , Genômica , Isolamento Reprodutivo
11.
Glob Chang Biol ; 27(23): 6086-6102, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34543498

RESUMO

Biological invasions represent one of the main threats to marine biodiversity. From a conservation perspective, especially in the context of increasing sea warming, it is critical to examine the suitability potential of geographical areas for the arrival of Range-Expanding Introduced and Native Species (REINS), and hence anticipate the risk of such species to become invasive in their new distribution areas. Here, we developed an empirical index, based on functional and bio-ecological traits, that estimates the Invasive Potential (IP; i.e. the potential success in transport, introduction and population establishment) for a set of 13 fishes that are expanding their distributional range into the Mediterranean Sea, the most invaded sea in the world. The IP index showed significant correlation with the observed spreading of REINS. For the six species characterized by the highest IP, we calculated contemporary and future projections of their Environmental Suitability Index (ESI). By using an ensemble modelling approach, we estimated the geographical areas that are likely to be the most impacted by REINS spreading under climate change. Our results demonstrated the importance of functional traits related to reproduction for determining high invasion potential. For most species, we found high contemporary ESI values in the South-eastern Mediterranean Sea and low to intermediate contemporary ESI values in the Adriatic Sea and North-western Mediterranean sector. Moreover, we highlighted a major potential future expansion of high ESI values, and thus REINS IP, towards the northern Mediterranean, especially in the northern Adriatic Sea. This potential future northward expansion highlights the risk associated with climate-induced impacts on ecosystem conservation and fish stock management throughout the entire Mediterranean Sea.


Assuntos
Mudança Climática , Espécies Introduzidas , Animais , Ecossistema , Peixes , Mar Mediterrâneo
12.
J Environ Manage ; 298: 113472, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34365186

RESUMO

Quarrying activities cause profound modifications on ecosystems, such as removal of vegetation cover, biodiversity loss and depletion of ecosystem services. Ecological restoration stands as a solution to revert such effects. Concomitantly, awareness is currently being given on ecosystem services and ecological processes to evaluate restoration efficiency. The objective of the study was to assess restoration success in a quarry subjected to restoration practices for the last 40 years involving the plantation of native Mediterranean vegetation and the non-native Aleppo pine Pinus halepensis. The study was carried out by assessing the effectiveness of seed dispersal service provided by birds in the restored quarry by comparing this service to neighbouring natural (shrubland) and other semi-natural areas (oak-pine mixed open and Aleppo pine forest) present at the landscape. For this purpose, we explored bird composition structure and seed dispersal networks using point counts and faecal samples of mist-netted birds. We also collected vegetation structure data and explored its effect on bird community composition. Our results showed that bird abundance in the restored quarry was significantly lower, and its bird community was compositionally different than natural shrubland and semi-natural areas. For instance, seed-dispersing birds, woody and shrub/ground foragers and partially migrators were the most affected groups at the restored area. Bird community composition and their traits were likely driven by vegetation characteristics, with higher native vegetation cover and fruit richness promoting higher bird abundance and Aleppo pine cover negatively influencing seed-dispersing birds. Concurrently, seed dispersal network in the restored quarry was less complex than in other areas. Seed dispersal services in the restored quarry were below the reported values for neighbouring natural and semi-natural areas and are likely driven by the low abundance of seed-dispersing birds. We consider that the causes affecting this group's low abundance can be related to revegetation measures favouring Aleppo pine, combined with a shallow soil depth and poor soil quality, which may have constrained native vegetation development. We conclude that seed dispersal services at the quarry are depleted, which may suggest a low restoration success concerning ecosystem functioning. Our results strengthen that quarry revegetation with non-native species must be avoided, since it alters bird community composition, and consequently, affects seed dispersal service provided by birds.


Assuntos
Dispersão de Sementes , Animais , Biodiversidade , Aves , Ecossistema , Florestas
13.
J Anim Ecol ; 89(11): 2496-2507, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32745261

RESUMO

Anthropogenic activity underpins the creation of urban ecosystems, often with introduced or invasive species playing a large role in structuring ecological communities. While the effects of urbanization on charismatic taxa such as birds, bees or butterflies have received much attention, the impacts on small and inconspicuous organisms remain poorly understood. Here, we assess how the community structure of leaf litter-inhabiting microarthropods in city parks varies along an urbanization gradient in Toronto, Canada. At each park, we established paired forest understorey plots which were either dominated by native vegetation or dog-strangling vine Vincetoxicum rossicum, an invasive species that is spreading throughout northeastern North America and abundant in urban areas. We compared microarthropod richness, abundance and diversity in ecological traits between invaded and non-invaded plots as well as compositional dissimilarities among plots across the urbanization gradient. We recorded 123 genera and found (a) there was a negative effect of urbanization on microarthropod richness and abundance but only in invaded plots; (b) richness and abundance increased continuously with urbanization in non-invaded plots, but peaked at intermediate urbanization levels in invaded plots and (c) there was significant turnover with increasing urbanization, with distinct communities represented in highly urbanized areas compared to less urbanized areas, regardless of whether invaded. We also found litter microarthropod richness and abundance increased with soil ammonium and decreased with nitrate. These trends were especially strong for fungivorous microarthropods; however, there was no relationship between soil nutrients and urbanization or invasion. Urbanization and biological invasion drive biodiversity change, and there is a need to disentangle these effects on ecological communities and related ecosystem processes. We show microarthropod communities change with urbanization, with the effects of invasion most prominent in non-urban areas. Here, there is high richness and abundance but low ecological trait diversity, possibly because certain feeding traits are excluded and others overrepresented. Understanding of urban ecological systems must include knowledge of the microarthropods that interact widely across food webs, form distinct communities in highly urban areas and drive many of the important ecological functions upon which people in cities depend.


Assuntos
Borboletas , Urbanização , Animais , Abelhas , Biodiversidade , Canadá , Cidades , Cães , Ecossistema
14.
Glob Chang Biol ; 25(10): 3424-3437, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31006156

RESUMO

Trait diversity is believed to influence ecosystem dynamics through links between organismal traits and ecosystem processes. Theory predicts that key traits and high trait redundancy-large species richness and abundance supporting the same traits-can buffer communities against environmental disturbances. While experiments and data from simple ecological systems lend support, large-scale evidence from diverse, natural systems under major disturbance is lacking. Here, using long-term data from both temperate (English Channel) and tropical (Seychelles Islands) fishes, we show that sensitivity to disturbance depends on communities' initial trait structure and initial trait redundancy. In both ecosystems, we found that increasing dominance by climatically vulnerable traits (e.g., small, fast-growing pelagics/corallivores) rendered fish communities more sensitive to environmental change, while communities with higher trait redundancy were more resistant. To our knowledge, this is the first study demonstrating the influence of trait structure and redundancy on community sensitivity over large temporal and spatial scales in natural systems. Our results exemplify a consistent link between biological structure and community sensitivity that may be transferable across ecosystems and taxa and could help anticipate future disturbance impacts on biodiversity and ecosystem functioning.


Assuntos
Ecossistema , Peixes , Animais , Biodiversidade
15.
Glob Chang Biol ; 25(11): 3972-3984, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31376310

RESUMO

Describing the spatial and temporal dynamics of communities is essential for understanding the impacts of global environmental change on biodiversity and ecosystem functioning. Trait-based approaches can provide better insight than species-based (i.e. taxonomic) approaches into community assembly and ecosystem functioning, but comparing species and trait dynamics may reveal important patterns for understanding community responses to environmental change. Here, we used a 33-year database of fish monitoring to compare the spatio-temporal dynamics of taxonomic and trait structure in North Sea fish communities. We found that the majority of variation in both taxonomic and trait structure was explained by a pronounced spatial gradient, with distinct communities in the southern and northern North Sea related to depth, sea surface temperature, salinity and bed shear stress. Both taxonomic and trait structure changed significantly over time; however taxonomically, communities in the south and north diverged towards different species, becoming more dissimilar over time, yet they converged towards the same traits regardless of species differences. In particular, communities shifted towards smaller, faster growing species with higher thermal preferences and pelagic water column position. Although taxonomic structure changed over time, its spatial distribution remained relatively stable, whereas in trait structure, the southern zone of the North Sea shifted northward and expanded, leading to homogenization. Our findings suggest that global environmental change, notably climate warming, will lead to convergence towards traits more adapted for novel environments regardless of species composition.


Assuntos
Ecossistema , Peixes , Animais , Biodiversidade , Fenótipo , Temperatura
16.
Proc Natl Acad Sci U S A ; 113(29): 8018-24, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27432974

RESUMO

For three decades, comparative phylogeography has conceptually and methodologically relied on the concordance criterion for providing insights into the historical/biogeographic processes driving population genetic structure and divergence. Here we discuss how this emphasis, and the corresponding lack of methods for extracting information about biotic/intrinsic contributions to patterns of genetic variation, may bias our general understanding of the factors driving genetic structure. Specifically, this emphasis has promoted a tendency to attribute discordant phylogeographic patterns to the idiosyncracies of history, as well as an adherence to generic null expectations of concordance with reduced predictive power. We advocate that it is time for a paradigm shift in comparative phylogeography, especially given the limited utility of the concordance criterion as genomic data provide ever-increasing levels of resolution. Instead of adhering to the concordance-discordance dichotomy, comparative phylogeography needs to emphasize the contribution of taxon-specific traits that will determine whether concordance is a meaningful criterion for evaluating hypotheses or may predict discordant phylogeographic structure. Through reference to some case studies we illustrate how refined hypotheses based on taxon-specific traits can provide improved predictive frameworks to forecast species responses to climatic change or biogeographic barriers while gaining unique insights about the taxa themselves and their interactions with their environment. We outline a potential avenue toward a synthetic comparative phylogeographic paradigm that includes addressing some important conceptual and methodological challenges related to study design and application of model-based approaches for evaluating support of trait-based hypotheses under the proposed paradigm.


Assuntos
Modelos Genéticos , Fenótipo , Variação Genética , Filogeografia
17.
Ecol Lett ; 21(9): 1401-1412, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30019409

RESUMO

The composition of local mammalian carnivore communities has far-reaching effects on terrestrial ecosystems worldwide. To better understand how carnivore communities are structured, we analysed camera trap data for 108 087 trap days across 12 countries spanning five continents. We estimate local probabilities of co-occurrence among 768 species pairs from the order Carnivora and evaluate how shared ecological traits correlate with probabilities of co-occurrence. Within individual study areas, species pairs co-occurred more frequently than expected at random. Co-occurrence probabilities were greatest for species pairs that shared ecological traits including similar body size, temporal activity pattern and diet. However, co-occurrence decreased as compared to other species pairs when the pair included a large-bodied carnivore. Our results suggest that a combination of shared traits and top-down regulation by large carnivores shape local carnivore communities globally.


Assuntos
Carnívoros , Ecologia , Ecossistema , Animais , Simpatria
18.
Ecol Lett ; 21(10): 1515-1529, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30133154

RESUMO

Dispersal is a fundamental ecological process, yet demonstrating the occurrence and importance of long-distance dispersal (LDD) remains difficult, having rarely been examined for widespread, non-coastal plants. To address this issue, we integrated phylogenetic, molecular dating, biogeographical, ecological, seed biology and oceanographic data for the inland Urticaceae. We found that Urticaceae originated in Eurasia c. 69 Ma, followed by ≥ 92 LDD events between landmasses. Under experimental conditions, seeds of many Urticaceae floated for > 220 days, and remained viable after 10 months in seawater, long enough for most detected LDD events, according to oceanographic current modelling. Ecological traits analyses indicated that preferences for disturbed habitats might facilitate LDD. Nearly half of all LDD events involved dioecious taxa, so population establishment in dioecious Urticaceae requires multiple seeds, or occasional selfing. Our work shows that seawater LDD played an important role in shaping the geographical distributions of Urticaceae, providing empirical evidence for Darwin's transoceanic dispersal hypothesis.


Assuntos
Urticaceae , Ecologia , Ecossistema , Filogenia , Sementes
19.
Glob Chang Biol ; 24(3): 925-932, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29215778

RESUMO

Given the global continuous rise, artificial light at night is often considered a driving force behind moth population declines. Although negative effects on individuals have been shown, there is no evidence for effects on population sizes to date. Therefore, we compared population trends of Dutch macromoth fauna over the period 1985-2015 between moth species that differ in phototaxis and adult circadian rhythm. We found that moth species that show positive phototaxis or are nocturnally active have stronger negative population trends than species that are not attracted to light or are diurnal species. Our results indicate that artificial light at night is an important factor in explaining declines in moth populations in regions with high artificial night sky brightness. Our study supports efforts to reduce the impacts of artificial light at night by promoting lamps that do not attract insects and reduce overall levels of illumination in rural areas to reverse declines of moth populations.


Assuntos
Ritmo Circadiano , Luz , Iluminação , Mariposas/fisiologia , Animais , Conservação dos Recursos Naturais , Comportamento Alimentar , Países Baixos , Fototaxia , Dinâmica Populacional
20.
Glob Chang Biol ; 24(1): e80-e89, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28727210

RESUMO

Recent decades have seen profound changes in species abundance and community composition. In the marine environment, the major anthropogenic drivers of change comprise exploitation, invasion by nonindigenous species, and climate change. However, the magnitude of these stressors has been widely debated and we lack empirical estimates of their relative importance. In this study, we focused on Eastern Mediterranean, a region exposed to an invasion of species of Red Sea origin, extreme climate change, and high fishing pressure. We estimated changes in fish abundance using two fish trawl surveys spanning a 20-year period, and correlated these changes with estimated sensitivity of species to the different stressors. We estimated sensitivity to invasion using the trait similarity between indigenous and nonindigenous species; sensitivity to fishing using a published composite index based on the species' life-history; and sensitivity to climate change using species climatic affinity based on occurrence data. Using both a meta-analytical method and random forest analysis, we found that for shallow-water species the most important driver of population size changes is sensitivity to climate change. Species with an affinity to warm climates increased in relative abundance and species with an affinity to cold climates decreased suggesting a strong response to warming local sea temperatures over recent decades. This decrease in the abundance of cold-water-associated species at the trailing "warm" end of their distribution has been rarely documented. Despite the immense biomass of nonindigenous species and the presumed high fishing pressure, these two latter factors seem to have only a minor role in explaining abundance changes. The decline in abundance of indigenous species of cold-water origin indicates a future major restructuring of fish communities in the Mediterranean in response to the ongoing warming, with unknown impacts on ecosystem function.


Assuntos
Adaptação Fisiológica , Mudança Climática , Ecossistema , Peixes/fisiologia , Temperatura , Distribuição Animal , Animais , Peixes/classificação , Oceano Índico , Mar Mediterrâneo
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