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1.
Ecol Lett ; 26 Suppl 1: S11-S15, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36731905

RESUMO

Despite decades of research on the interactions between ecology and evolution, opportunities still remain to further integrate the two disciplines, especially when considering multispecies systems. Here, we discuss two such opportunities. First, the traditional emphasis on the distinction between evolutionary and ecological processes should be further relaxed as it is particularly unhelpful in the study of microbial communities, where the very notion of species is hard to define. Second, key processes of evolutionary theory such as adaptation should be exported to hierarchical levels higher than populations to make sense of biodiversity dynamics. Together, we argue that broadening our perspective of eco-evolutionary dynamics to be more inclusive of all biodiversity, both phylogenetically and hierarchically, will open up fertile new research directions and help us to address one of the major scientific challenges of our time, that is, to understand and predict changes in biodiversity in the face of rapid environmental change.

2.
Ecol Evol ; 12(11): e9471, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36340816

RESUMO

Climate change has dramatic impacts on ecological systems, affecting a range of ecological factors including phenology, species abundance, diversity, and distribution. The breadth of climate change impacts on ecological systems leads to the occurrence of fingerprints of climate change. However, climate fingerprints are usually identified across broad geographical scales and are potentially influenced by publication biases. In this study, we used natural history collections spanning over 250 years, to quantify a range of ecological responses to climate change, including phenology, abundance, diversity, and distributions, across a range of taxa, including vertebrates, invertebrates, plants, and fungi, within a single region, Central Norway. We tested the hypotheses that ecological responses to climate change are apparent and coherent at a regional scale, that longer time series show stronger trends over time and in relation to temperature, and that ecological responses change in trajectory at the same time as shifts in temperature. We identified a clear regional coherence in climate signal, with decreasing abundances of limnic zooplankton (on average by 7691 individuals m-3 °C-1) and boreal forest breeding birds (on average by 1.94 territories km-2 °C-1), and earlier plant flowering phenology (on average 2 days °C-1) for every degree of temperature increase. In contrast, regional-scale species distributions and species diversity were largely stable. Surprisingly, the effect size of ecological response did not increase with study duration, and shifts in responses did not occur at the same time as shifts in temperature. This may be as the long-term studies include both periods of warming and temperature stability, and that ecological responses lag behind warming. Our findings demonstrate a regional climate fingerprint across a long timescale. We contend that natural history collections provide a unique window on a broad spectrum of ecological responses at timescales beyond most ecological monitoring programs. Natural history collections are thus an essential source for long-term ecological research.

4.
Ecology ; 103(1): e03527, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469586

RESUMO

Wisconsin's plant communities are responding to shifting disturbance regimes, habitat fragmentation, aerial nitrogen deposition, exotic species invasions, ungulate herbivory, and successional processes. To better understand how plant functional traits mediate species' responses to changing environmental conditions, we collected a large set of functional trait data for vascular plant species occupying Wisconsin forests and grasslands. We used standard protocols to make 76,213 measurements of 34 quantitative traits. These data provide rich information on genome size, physical leaf traits (length, width, circularity, thickness, dry matter content, specific leaf area, etc.), chemical leaf traits (carbon, nitrogen, phosphorus, potassium, calcium, magnesium, ash), life history traits (vegetative and flower heights, seed mass), and traits affecting plant palatability (leaf fiber, fat, and lignin). These trait values derive from replicate measurements on 12+ individuals of each species from multiple sites and 45+ individuals for a selected subset of species. Measurements typically reflect values for individuals although some chemical traits involved composite samples from several individuals at the same site. We also qualitatively characterized each species by plant family, woodiness, functional group, and Raunkiaer lifeform. These data allow us to characterize trait dimensionality, differentiation, and covariation among temperate plant species (e.g., leaf and stem economic syndromes). We can also characterize species' responses to environmental gradients and drivers of ecological change. With survey and resurvey data available from >400 sites in Wisconsin, we can analyze variation in community trait distributions and diversity over time and space. These data therefore allow us to assess how trait divergence vs. convergence affects community assembly and how traits may be related to half-century shifts in the distribution and abundance of these species. The data set can be used for non-commercial purposes. The data set is licensed as follows: CC-By Attribution 4.0 International. We request users cite both the OSF data set and this Ecology data paper publication.


Assuntos
Florestas , Plantas/classificação , América do Norte , Folhas de Planta
5.
Heliyon ; 6(10): e05220, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33102846

RESUMO

Mountains support a great diversity of species and habitat types. Grasslands are the dominant landscape in the Andes and play an important ecological role. However, they are threatened by many factors, including climate change and human activities. The spatial distribution of species that compose, and the ecological and evolutionary factors that provide for the spatial biodiversity patterns, are little known. The largest Poa L. (Poaceae) genera are widely diversified and distributed in the Andes. In particular, P. scaberula Hook. f. shows great environmentally mediated phenotypic plasticity, and is distributed from North America to the tip of South America. However, the impact of environmental variables has on the spatial distribution of this species, remain largely unknown. Using high-resolution climatic data, herein we modeled the current suitable habitat for P. scaberula and identified the main climatic variables that best predict its potential distribution. In addition, we assess the species status in the predicted habitats through herbarium data and relate it with species distribution models. The models showed that P. scaberula has a suitable habitat of ca. 162.747 km2 along the Andes and high elevation regions. The most influential variables with a 68.5% contribution to the distribution of the species, particularly high elevation areas, included mean cold hardiness, water vapor pressure and temperature seasonality. The areas of greatest suitability with the highest occurrence of the species were identified geographically by the models. The present study provides useful information that can assist in the identification of areas where the species is most sensitive to different variables, including climate change and human activities and contributes in assessing the conservation status of Andean grassland at a regional scale.

6.
Heliyon ; 6(8): e04580, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32793826

RESUMO

The main aim of this study was to assess the level of mercury accumulation in the hair of students studying in the Vologda Region, Russia. Particular attention is devoted to clarifying the relationship between the metal concentration in the hair and the amount of fish in the diet. It was found that the mercury content in the hair of Vologda Region residents aged 17-21 is in the range from less than 0.002 mg/kg to 1.69 mg/kg, the median of the indicator for the entire sample is 0.14 mg/kg. The median value of mercury content in the hair of males (0.12 mg/kg) is lower than in the hair of females (0.16 mg/kg). The lowest metal concentrations were observed in individuals living in the city of Cherepovets and the highest metal concentration among the entire sample and in females in the western areas, and males in the eastern areas of the Vologda Region. The concentration of metal in the hair of the urban population is lower than in subjects living in rural areas. A higher metal content in the hair was recorded in individuals whose diet usually contains fish twice a month.

7.
Mol Immunol ; 117: 131-138, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31770676

RESUMO

V(D)J recombination is a process of somatic recombination catalyzed by proteins encoded by RAG1 and RAG2 genes, both restricted to the genome of jawed vertebrates. Their proteins constitute the enzymatic core of V(D)J recombination machinery and are crucial for jawed vertebrate adaptive immunity. Mammals possess great ecological diversity, and their complex evolutionary history associated with radiation to different environments presented many distinct pathogenic challenges from these different habitats. Cetaceans comprise a mammalian order of fully aquatic mammals that have arisen from a complete terrestrial ancestor and, accordingly, was confronted with challenges from changing environmental pathogens while they transitioned from land to sea. In this study we undertook molecular evolutionary analyses of RAG1 and RAG2 genes, exploring the possible role of natural selection acting on these genes focusing on the cetacean lineage. We performed phylogenetic reconstructions on IQ-TREE, together with selection analyses in the codeml program of the PAML package, and in the FITMODEL program for codon evolution and switching on both the RAG1 and RAG2 genes. Our findings demonstrate that RAG1 and RAG2 remained fairly conserved among tetrapods, with purifying selection acting on both genes, with evidence for a few punctuated shifts in nucleotide substitution rates of both genes along tetrapod evolution. We demonstrate differential evolution in the closely linked genes RAG1 and RAG2 specifically in cetaceans.


Assuntos
Evolução Biológica , Cetáceos/genética , Cetáceos/imunologia , Proteínas de Ligação a DNA/genética , Genes RAG-1/genética , Animais , Proteínas de Ligação a DNA/imunologia , Genes RAG-1/imunologia , Filogenia
8.
Heliyon ; 5(9): e02482, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687576

RESUMO

The abundance and properties of small standing water bodies (SSWB) is globally not well known for their ecological importance is undervalued and their detection suffers from technical limitations. In the current study, we used a combination of GIS-based methods (satellite, orthophoto, ground validation) to evaluate regional estimates of standing water body (SWB) inventories in two geographically different parts of Europe - France, and Estonia. In our study the SWBs surface area threshold limit was 0.00001 km2, exceeding the limits of previous studies (>0.002 km2). The total number of SWBs in Estonia is 111 552 (2.5 per km2) and in France 598 371 (1.1 per km2). Our estimates show that the median size of SWBs in Estonia and France is 0.0003 km2 and 0.0007 km2 respectively, meaning that most of the SSWBs are not included in the global inventories, and their number is therefore underestimated. SSWBs (area below 0.01 km2) form a significant share of the total shoreline length of SWBs, 70.3% in Estonia and 58.8% in France. As nearshore areas are often very productive with diverse habitats, the SSWBs hold a crucial role in maintaining biodiversity. Our results provide quantitative evidence that SSWBs are vital and abundant landscape elements, freshwater resources, and habitats that should not be ignored in global inventories.

9.
Ecology ; 98(9): 2356-2369, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28500791

RESUMO

Disturbance can catalyze rapid ecological change by causing widespread mortality and initiating successional pathways, and during times of climate change, disturbance may contribute to ecosystem state changes by initiating a new successional pathway. In the Pacific Northwest of North America (PNW), disturbance by wildfires strongly shapes the composition and structure of lowland forests, but understanding the role of fire over periods of climate change is challenging, because fire-return intervals are long (e.g., millennia) and the coniferous trees dominating these forests can live for many centuries. We developed stand-scale paleorecords of vegetation and fire that span nearly the past 14,000 yr to study how fire was associated with state changes and rapid dynamics in forest vegetation at the stand scale (1-3 ha). We studied forest history with sediment cores from small hollow sites in the Marckworth State Forest, located ~1 km apart in the Tsuga heterophylla Zone in the Puget Lowland ecoregion of western Washington, USA. The median rate of change in pollen/spore assemblages was similar between sites (0.12 and 0.14% per year), but at both sites, rates of change increased significantly following fire events (ranging up to 1% per year, with a median of 0.28 and 0.38%, P < 0.003). During times of low climate velocity, forest composition was resilient to fires, which initiated successional pathways leading back to the dominant vegetation type. In contrast, during times of high climate variability and velocity (e.g., the early Holocene) forests were not resilient to fires, which triggered large-scale state changes. These records provide clear evidence that disturbance, in the form of an individual fire event, can be an important catalyst for rapid state changes, accelerating vegetation shifts in response to large-scale climate change.


Assuntos
Mudança Climática , Ecossistema , Incêndios , Florestas , Sedimentos Geológicos , Noroeste dos Estados Unidos , Traqueófitas , Árvores
10.
Glob Chang Biol ; 22(5): 1737-45, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26666533

RESUMO

While ecological effects on short-term population dynamics are well understood, their effects over millennia are difficult to demonstrate and convincing evidence is scant. Using coalescent methods, we analysed past population dynamics of three lizard species (Psammodromus hispanicus, P. edwardsianus, P. occidentalis) and linked the results with climate change data covering the same temporal horizon (120 000 years). An increase in population size over time was observed in two species, and in P. occidentalis, no change was observed. Temporal changes in temperature seasonality and the maximum temperature of the warmest month were congruent with changes in population dynamics observed for the three species and both variables affected population density, either directly or indirectly (via a life-history trait). These results constitute the first solid link between ecological change and long-term population dynamics. The results moreover suggest that ecological change leaves genetic signatures that can be retrospectively traced, providing evidence that ecological change is a crucial driver of genetic diversity and speciation.


Assuntos
Evolução Biológica , Mudança Climática , Variação Genética , Lagartos/fisiologia , Animais , Lagartos/genética , Dinâmica Populacional , Espanha
11.
Hum Ecol Interdiscip J ; 43(3): 411-424, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26213437

RESUMO

This study assesses the nutritional status of Maasai pastoralists living in a period of great social, economic and ecological changes in Kajiado County, southern Kenya. Data on weight, height, skinfolds, and circumferences were collected from 534 individuals in the year 2000. The data were used to describe mean differences in human nutrition between ages, sexes, and within and among three Group Ranches. Nutritional data and diet recall data were compared with past studies of Maasai nutrition from 1930 to 2000. Results indicate that nutritional status is poor and has remained so despite numerous changes to the social-ecological system including livelihood diversification, sedentarization, human population growth and decreased access to vegetation heterogeneity. Imbirikani Group Ranch had better access to infrastructure and markets and some measures of nutritional status were better than for individuals in other group ranches. However, nutritional status remains poor despite transitioning to greater market integration.

13.
Soc Sci Med ; 129: 20-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24673887

RESUMO

The "One World One Health Initiative" has attended little to the priorities, concepts and practices of resource-poor communities confronting disease and the implications of these concerns for its biomedical, ecological and institutional approach to disease surveillance and control. Using the example of Buruli ulcer (BU) and its bacterial etiology, Mycobacterium ulcerans, in south-central Cameroon, we build on debates about the contributions of "local knowledge" and "alternative models" to biomedical knowledge of disease transmission. BU's mode of transmission remains poorly understood. Our approach employs ethno-ecological histories - local understandings of the putative emergence and expansion of a locally important, neglected disease. We develop these histories from 52 individual and small group interviews, group discussions, and participant-observation of daily and seasonal activities, conducted in 2013-2013. These histories offer important clues about past environmental and social change that should guide further ecological, epidemiological research. They highlight a key historical moment (the late 1980s and 1990s); specific ecological transformations; new cultivation practices in unexploited zones that potentially increased exposure to M. ulcerans; and ecological degradation that may have lowered nutritional standards and heightened susceptibility to BU. They also recast transmission, broadening insight into BU and its local analog, atom, by emphasizing the role of social change and economic crisis in its emergence and expansion.


Assuntos
Antropologia Cultural/história , Úlcera de Buruli/transmissão , Ecossistema , Amor , Mycobacterium ulcerans/isolamento & purificação , Animais , Úlcera de Buruli/epidemiologia , Camarões/epidemiologia , Relações Familiares , Saúde Global/economia , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Entrevistas como Assunto , Doenças Negligenciadas/história , Doenças Negligenciadas/prevenção & controle , Fatores Socioeconômicos
14.
Conserv Biol ; 28(3): 820-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24528101

RESUMO

When sudden catastrophic events occur, it becomes critical for coastal communities to detect and respond to environmental transformations because failure to do so may undermine overall ecosystem resilience and threaten people's livelihoods. We therefore asked how capable of detecting rapid ecological change following massive environmental disruptions local, indigenous people are. We assessed the direction and periodicity of experimental learning of people in the Western Solomon Islands after a tsunami in 2007. We compared the results of marine science surveys with local ecological knowledge of the benthos across 3 affected villages and 3 periods before and after the tsunami. We sought to determine how people recognize biophysical changes in the environment before and after catastrophic events such as earthquakes and tsunamis and whether people have the ability to detect ecological changes over short time scales or need longer time scales to recognize changes. Indigenous people were able to detect changes in the benthos over time. Detection levels differed between marine science surveys and local ecological knowledge sources over time, but overall patterns of statistically significant detection of change were evident for various habitats. Our findings have implications for marine conservation, coastal management policies, and disaster-relief efforts because when people are able to detect ecological changes, this, in turn, affects how they exploit and manage their marine resources.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Percepção , Tsunamis , Humanos , Melanesia
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