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1.
Heliyon ; 9(9): e19783, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809595

RESUMO

Wildlife-vehicle collision (WVC) is one of the major causes of wildlife mortality and a concern for conservationists worldwide. The study of roadkill data that can be used to develop appropriate measures and strategies for both wildlife conservation and traffic safety to mitigate the WVC and animals' mortality. Extensive studies have been conducted in the developed countries on the identification of WVC hotspots and its potential impact; however, less attention is given in developing countries. Because of this, the problem is not well understood in developing countries. This study was intended to identify victim species, hotspot areas for roadkill, and factors that contribute to WVC in Jimma Zone, along three roads leading from Jimma City. Data were collected using a citizen science approach and a skilled man power road survey (March-September 2022) to document the number and type of species killed. Three road segments (135 km in total) were surveyed weekly as a baseline for future research. All statistical analyses were carried out using R-software. In the present study, a total of 84 roadkill specimens were collected from 16 different mammal species, of which 85.7% were medium-sized carnivores. The findings showed that Jackals (Canis mesomalis and Canis adustus) were the most frequently killed species (25%, n is 21), followed by Civettictis civetta (22.62%, n is 19). The study revealed that the major factors causing collisions include habitat type (forest cover) and wildlife behavior (nocturnal or diurnal). Further, the study revealed that the majority of WVC occurred at night (dusk) and at dawn in areas that are covered with dense forests. To minimize the potential risks of WVC and animals' mortality, we suggest putting warning signs in hotspot areas where roadkill usually occur frequently. In addition, we recommend creating awareness among drivers, traffic police, and all communities about the negative impacts and consequences of collisions on the ecological and economic value of wildlife.

3.
Nat Commun ; 14(1): 1569, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944651

RESUMO

Ensuring a more equitable distribution of vaccines worldwide is an effective strategy to control global pandemics and support economic recovery. We analyze the socioeconomic effects - defined as health gains, lockdown-easing effect, and supply-chain rebuilding benefit - of a set of idealized COVID-19 vaccine distribution scenarios. We find that an equitable vaccine distribution across the world would increase global economic benefits by 11.7% ($950 billion per year), compared to a scenario focusing on vaccinating the entire population within vaccine-producing countries first and then distributing vaccines to non-vaccine-producing countries. With limited doses among low-income countries, prioritizing the elderly who are at high risk of dying, together with the key front-line workforce who are at high risk of exposure is projected to be economically beneficial (e.g., 0.9%~3.4% annual GDP in India). Our results reveal how equitable distributions would cascade more protection of vaccines to people and ways to improve vaccine equity and accessibility globally through international collaboration.


Assuntos
COVID-19 , Vacinas , Humanos , Idoso , Vacinas contra COVID-19 , Saúde Global , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis
5.
J Hazard Mater ; 424(Pt C): 127570, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34753647

RESUMO

Coastal ecosystem health is of vital importance to human well-being. Field investigations of major pollutants along the whole coast of China were carried out to explore associations between coastal development activities and pollutant inputs. Measurements of target pollutants such as PFAAs and PAHs uncovered notable levels in small estuary rivers. The Yangtze River was identified to deliver the highest loads of these pollutants to the seas as a divide for the spatial distribution of pollutant compositions. Soil concentrations of the volatile and semi-volatile pollutants showed a cold-trapping effect in pace with increasing latitudinal gradient. The coastal ecosystem is facing high ecological risks from metal pollution, especially copper (Cu) and zinc (Zn), while priority pollutants of high risks vary for different kinds of protected species, and the ecological risks were influenced by both climate and physicochemical properties of environmental matrices, which should be emphasized to protect and restore coastal ecosystem functioning.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Oceanos e Mares , Medição de Risco , Rios , Poluentes Químicos da Água/análise
6.
Glob Chang Biol ; 27(16): 3732-3740, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33993582

RESUMO

Animal populations at northern latitudes may have cyclical dynamics that are degraded by climate change leading to trophic cascade. Hare populations at more southerly latitudes are characterized by dramatic declines in abundance associated with agricultural intensification. We focus on the impact of historical climatic and agricultural change on a mid-latitude population of mountain hares, Lepus timidus hibernicus. Using game bag records from multiple sites throughout Ireland, the hare population index exhibited a distinct regime shift. Contrary to expectations, there was a dynamical structure typical of northern latitude hare populations from 1853 to 1908, during which numbers were stable but cyclic with a periodicity of 8 years. This regime was replaced by dynamics more typical of southern latitude hare populations from 1909 to 1970, in which cycles were lost and numbers declined dramatically. Destabilization of the autumn North Atlantic Oscillation (NAO) led to the collapse of similar cycles in the hare population, coincident with the onset of agricultural intensification (a shift from small-to-large farms) in the first half of the 20th century. Similar, but more recent regime shifts have been observed in Arctic ecosystems and attributed to anthropogenic climate change. The present study suggests such shifts may have occurred at lower latitudes more than a century ago during the very early 20th century. It seems likely that similar tipping points in the population collapse of other farmland species may have occurred similarly early but went undocumented. As northern systems are increasingly impacted by climate change and probable expansion of agriculture, the interaction of these processes is likely to disrupt the pulsed flow of resources from cyclic populations impacting ecosystem function.


Assuntos
Lebres , Agricultura , Animais , Regiões Árticas , Ecossistema , Irlanda , Dinâmica Populacional
7.
Sci Adv ; 7(12)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33741585

RESUMO

Current food production and consumption trends are inconsistent with the Convention on Biological Diversity's 2050 vision of living in harmony with nature. Here, we examine how, and under what conditions, the post-2020 biodiversity framework can support transformative change in food systems. Our analysis of actions proposed in four science-policy fora reveals that subsidy reform, valuation, food waste reduction, sustainability standards, life cycle assessments, sustainable diets, mainstreaming biodiversity, and strengthening governance can support more sustainable food production and consumption. By considering barriers and opportunities of implementing these actions in Peru and the United Kingdom, we derive potential targets and indicators for the post-2020 biodiversity framework. For targets to support transformation, genuine political commitment, accountability and compliance, and wider enabling conditions and actions by diverse agents are needed to shift food systems onto a sustainable path.


Assuntos
Alimentos , Eliminação de Resíduos , Biodiversidade , Conservação dos Recursos Naturais , Dieta , Peru
8.
BMC Ecol ; 20(1): 70, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334346

RESUMO

BACKGROUND: Earlier breeding is one of the strongest responses to global change in birds and is a key factor determining reproductive success. In most studies of climate effects, the focus has been on large-scale environmental indices or temperature averaged over large geographical areas, neglecting that animals are affected by the local conditions in their home ranges. In riverine ecosystems, climate change is altering the flow regime, in addition to changes resulting from the increasing demand for renewable and clean hydropower. Together with increasing temperatures, this can lead to shifts in the time window available for successful breeding of birds associated with the riverine habitat. Here, we investigated specifically how the environmental conditions at the territory level influence timing of breeding in a passerine bird with an aquatic lifestyle, the white-throated dipper Cinclus cinclus. We relate daily river discharge and other important hydrological parameters, to a long-term dataset of breeding phenology (1978-2015) in a natural river system. RESULTS: Dippers bred earlier when winter river discharge and groundwater levels in the weeks prior to breeding were high, and when there was little snow in the catchment area. Breeding was also earlier at lower altitudes, although the effect dramatically declined over the period. This suggests that territories at higher altitudes had more open water in winter later in the study period, which permitted early breeding also here. Unexpectedly, the largest effect inducing earlier breeding time was territory river discharge during the winter months and not immediately prior to breeding. The territory river discharge also increased during the study period. CONCLUSIONS: The observed earlier breeding can thus be interpreted as a response to climate change. Measuring environmental variation at the scale of the territory thus provides detailed information about the interactions between organisms and the abiotic environment.


Assuntos
Hidrologia , Passeriformes , Animais , Cruzamento , Mudança Climática , Ecossistema
9.
Folia Primatol (Basel) ; 91(6): 669-687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126549

RESUMO

With 60% of all primate species now threatened with extinction and many species only persisting in small populations in forest fragments, conservation action is urgently needed. But what type of action? Here we argue that restoration of primate habitat will be an essential component of strategies aimed at conserving primates and preventing the extinctions that may occur before the end of the century and propose that primates can act as flagship species for restoration efforts. To do this we gathered a team of academics from around the world with experience in restoration so that we could provide examples of why primate restoration ecology is needed, outline how primates can act as flagship species for restoration efforts of tropical forest, review what little is known about how primate populations respond to restoration efforts, and make specific recommendations of the next steps needed to make restoration of primate populations successful. We set four priorities: (1) academics must effectively communicate both the value of primates and the need for restoration; (2) more research is needed on how primates contribute to forest restoration; (3) more effort must be put into Masters and PhD level training for tropical country nationals; and finally (4) more emphasis is needed to monitor the responses of regenerating forest and primate populations where restoration efforts are initiated. We are optimistic that populations of many threatened species can recover, and extinctions can be prevented, but only if concerted large-scale efforts are made soon and if these efforts include primate habitat restoration.


Assuntos
Conservação dos Recursos Naturais/métodos , Florestas , Primatas , Animais , Ecossistema , Recuperação e Remediação Ambiental , Extinção Biológica
10.
R Soc Open Sci ; 6(9): 190772, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31598305

RESUMO

African wolves (AWs) are sympatric with endangered Ethiopian wolves (EWs) in parts of their range. Scat analyses have suggested a dietary overlap between AWs and EWs, raising the potential for exploitative competition, and a possible conservation threat to EWs. However, in contrast to that of the well-studied EW, the foraging ecology of AWs remains poorly characterized. Accordingly, we studied the foraging ecology of radio-collared AWs (n = 11 individuals) at two localities with varying levels of anthropogenic disturbance in the Ethiopian Highlands, the Guassa-Menz Community Conservation Area (GMCCA) and Borena-Saynt National Park (BSNP), accumulating 845 h of focal observation across 2952 feeding events. We also monitored rodent abundance and rodent trapping activity by local farmers who experience conflict with AWs. The AW diet consisted largely of rodents (22.0%), insects (24.8%), and goats and sheep (24.3%). Of the total rodents captured by farmers using local traps during peak barley production (July to November) in GMCCA, averaging 24.7 ± 8.5 rodents/hectare/day, 81% (N = 3009) were scavenged by AWs. Further, of all the rodents consumed by AWs, most (74%) were carcasses. These results reveal complex interactions between AWs and local farmers, and highlight the scavenging niche occupied by AWs in anthropogenically altered landscapes in contrast to the active hunting exhibited by EWs in more intact habitats. While AWs cause economic damage to local farmers through livestock predation, they appear to play an important role in scavenging pest rodents among farmlands, a pattern of behaviour which likely mitigates direct and indirect competition with EWs. We suggest two routes to promote the coexistence of AWs and EWs in the Ethiopian highlands: local education efforts highlighting the complex role AWs play in highland ecosystems to reduce their persecution, and enforced protection of intact habitats to preserve habitat preferred by EWs.

11.
Ecol Evol ; 9(11): 6665-6677, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31236251

RESUMO

Translocation of organisms within or outside its native range carries the risk of modifying the community of the recipient ecosystems and induces gene flow between locally adapted populations or closely related species. In this study, we evaluated the genetic consequences of large-scale translocation of cleaner wrasses that has become a common practice within the salmon aquaculture industry in northern Europe to combat sea lice infestation. A major concern with this practice is the potential for hybridization of escaped organisms with the local, recipient wrasse population, and thus potentially introduce exogenous alleles and breaking down coadapted gene complexes in local populations. We investigated the potential threat for such genetic introgressions in a large seminatural mesocosm basin. The experimental setting represented a simulated translocation of corkwing wrasse (Symphodus melops) that occurs on a large scale in the Norwegian salmon industry. Parentage assignment analysis of mesocosm's offspring revealed 30% (195 out of 651 offspring) interbreeding between the two populations, despite their being genetically (F ST = 0.094, p < 0.05) and phenotypically differentiated. Moreover, our results suggest that reproductive fitness of the translocated western population doubled that of the local southern population. Our results confirm that human translocations may overcome the impediments imposed by natural habitat discontinuities and urge for immediate action to manage the genetic resources of these small benthic wrasses.

12.
Proc Natl Acad Sci U S A ; 116(9): 3624-3629, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808752

RESUMO

Dengue is a climate-sensitive mosquito-borne disease with increasing geographic extent and human incidence. Although the climate-epidemic association and outbreak risks have been assessed using both statistical and mathematical models, local mosquito population dynamics have not been incorporated in a unified predictive framework. Here, we use mosquito surveillance data from 2005 to 2015 in China to integrate a generalized additive model of mosquito dynamics with a susceptible-infected-recovered (SIR) compartmental model of viral transmission to establish a predictive model linking climate and seasonal dengue risk. The findings illustrate that spatiotemporal dynamics of dengue are predictable from the local vector dynamics, which in turn, can be predicted by climate conditions. On the basis of the similar epidemiology and transmission cycles, we believe that this integrated approach and the finer mosquito surveillance data provide a framework that can be extended to predict outbreak risk of other mosquito-borne diseases as well as project dengue risk maps for future climate scenarios.


Assuntos
Vírus da Dengue/patogenicidade , Dengue/epidemiologia , Surtos de Doenças , Mosquitos Vetores/genética , Animais , China , Mudança Climática , Culicidae/patogenicidade , Culicidae/virologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/genética , Vetores de Doenças , Modelos Teóricos , Mosquitos Vetores/virologia
13.
Primate Biol ; 6(1): 7-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32110714

RESUMO

Black-and-white colobus (Colobus guereza Rüppell, 1835) are arboreal Old World monkeys inhabiting large parts of the deciduous and evergreen forests of sub-Saharan Africa. Two of the eight subspecies of Colobus guereza are endemic to Ethiopia: C. g. gallarum and C. g. guereza. However, the validity of the Ethiopian taxa is debated and observed morphological differences were attributed to clinal variation within C. g. guereza. To date, no molecular phylogeny of the Ethiopian guerezas is available to facilitate their taxonomic classification. We used mitochondrial DNA markers from 94 samples collected across Ethiopia to reconstruct a phylogeny of respective mitochondrial lineages. In our phylogenetic reconstruction, augmented by orthologous sequence information of non-Ethiopian black-and-white colobus from GenBank, we found two major Ethiopian mitochondrial clades, with one being largely congruent with the distribution of C. g. guereza. The second clade was found only at two locations in the eastern part of the putative range of C. g. gallarum. This second lineage clustered with the lowland form, C. g. occidentalis, from central Africa, whereas the C. g. guereza lineages clustered with C. g. caudatus and C. g. kikuyuensis from Kenya and northern Tanzania. These two guereza lineages diverged around 0.7 million years ago. In addition, mitochondrial sequence information does not support unequivocally a distinction of C. g. caudatus and C. g. kikuyuensis. Our findings indicate a previous biogeographic connection between the ranges of C. g. occidentalis and C. g. gallarum and a possible secondary invasion of Ethiopia by members of the C. g. guereza-C. g. caudatus-C. g. kikuyuensis clade. Given these phylogenetic relationships, our study supports the two-taxa hypothesis, making C. g. gallarum an Ethiopian endemic, and, in combination with the taxon's very restricted range, makes it one of the most endangered subspecies of black-and-white colobus.

14.
Proc Natl Acad Sci U S A ; 115(50): E11790-E11797, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30478041

RESUMO

Over the last few years, genomic studies on Yersinia pestis, the causative agent of all known plague epidemics, have considerably increased in numbers, spanning a period of about 5,000 y. Nonetheless, questions concerning historical reservoirs and routes of transmission remain open. Here, we present and describe five genomes from the second half of the 14th century and reconstruct the evolutionary history of Y. pestis by reanalyzing previously published genomes and by building a comprehensive phylogeny focused on strains attributed to the Second Plague Pandemic (14th to 18th century). Corroborated by historical and ecological evidence, the presented phylogeny, which includes our Y. pestis genomes, could support the hypothesis of an entry of plague into Western European ports through distinct waves of introduction during the Medieval Period, possibly by means of fur trade routes, as well as the recirculation of plague within the human population via trade routes and human movement.


Assuntos
Pandemias/história , Peste/história , Yersinia pestis/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Europa (Continente)/epidemiologia , Evolução Molecular , Fósseis/microbiologia , Genoma Bacteriano , História Medieval , Humanos , Filogenia , Peste/epidemiologia , Peste/microbiologia , Polimorfismo de Nucleotídeo Único , Fatores de Tempo , Yersinia pestis/classificação
15.
Proc Natl Acad Sci U S A ; 115(41): 10422-10427, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30249639

RESUMO

Louse-borne relapsing fever (LBRF) is known to have killed millions of people over the course of European history and remains a major cause of mortality in parts of the world. Its pathogen, Borrelia recurrentis, shares a common vector with global killers such as typhus and plague and is known for its involvement in devastating historical epidemics such as the Irish potato famine. Here, we describe a European and historical genome of Brecurrentis, recovered from a 15th century skeleton from Oslo. Our distinct European lineage has a discrete genomic makeup, displaying an ancestral oppA-1 gene and gene loss in antigenic variation sites. Our results illustrate the potential of ancient DNA research to elucidate dynamics of reductive evolution in a specialized human pathogen and to uncover aspects of human health usually invisible to the archaeological record.


Assuntos
Proteínas de Bactérias/genética , Borrelia/genética , Genoma Bacteriano , Metagenômica , Febre Recorrente/genética , Adulto , Animais , Borrelia/classificação , Borrelia/patogenicidade , Criança , Feminino , História do Século XV , Humanos , Filogenia , Febre Recorrente/história , Febre Recorrente/microbiologia , Países Escandinavos e Nórdicos
16.
Evolution ; 72(11): 2325-2342, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30259522

RESUMO

In changing environments, phenotypic traits are shaped by numerous agents of selection. The optimal phenotypic value maximizing the fitness of an individual thus varies through time and space with various environmental covariates. Selection may differ between different life-cycle stages and act on correlated traits inducing changes in the distribution of several traits simultaneously. Despite increasing interests in environmental sensitivity of phenotypic selection, estimating varying selective optima on various traits throughout the life cycle, while considering (a)biotic factors as potential selective agents has remained challenging. Here, we provide a statistical model to measure varying selective optima from longitudinal data. We apply our approach to analyze environmental sensitivity of phenotypic selection on egg-laying date and clutch size throughout the life cycle of a white-throated dipper population. We show the presence of a joint optimal phenotype that varies over the 35-year period, being dependent on altitude and temperature. We also find that optimal laying date is density-dependent, with high population density favoring earlier laying dates. By providing a flexible approach, widely applicable to free-ranging populations for which long-term data on individual phenotypes, fitness, and environmental factors are available, our study improves the understanding of phenotypic selection in varying environments.


Assuntos
Tamanho da Ninhada , Oviposição/fisiologia , Passeriformes/fisiologia , Fenótipo , Fatores Etários , Altitude , Animais , Feminino , Estágios do Ciclo de Vida , Modelos Estatísticos , Noruega , Densidade Demográfica , Temperatura
18.
R Soc Open Sci ; 5(5): 172207, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29892409

RESUMO

Carnivore populations are declining globally due to range contraction, persecution and prey depletion. One consequence of these patterns is increased range and niche overlap with other carnivores, and thus an elevated potential for competitive exclusion. Here, we document competition between an endangered canid, the Ethiopian wolf (EW), and the newly discovered African wolf (AW) in central Ethiopia. The diet of the ecological specialist EW was dominated by rodents, whereas the AW consumed a more diverse diet also including insects and non-rodent mammals. EWs used predominantly intact habitat, whereas AWs used mostly areas disturbed by humans and their livestock. We observed 82 encounters between the two species, of which 94% were agonistic. The outcomes of agonistic encounters followed a territory-specific dominance pattern, with EWs dominating in intact habitat and AWs in human-disturbed areas. For AWs, the likelihood of winning encounters also increased with group size. Rodent species consumed by EWs were also available in the human-disturbed areas, suggesting that these areas could be suitable habitat for EWs if AWs were not present. Increasing human encroachment not only affects the prey base of EWs, but also may impact their survival by intensifying competition with sympatric AWs.

19.
Biol Lett ; 14(6)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29875207

RESUMO

Intralocus sexual conflicts arise whenever the fitness optima for a trait expressed in both males and females differ between the sexes and shared genetic architecture constrains the sexes from evolving independently towards their respective optima. Such sexual conflicts are commonplace in nature, yet their long-term evolutionary consequences remain unexplored. Using a Bayesian phylogenetic comparative framework, we studied the macroevolutionary dynamics of intersexual trait integration in stalk-eyed flies (Diopsidae) spanning a time frame of more than 25 Myr. We report that increased intensity of sexual selection on male eyestalks is associated with reduced intersexual eyestalk integration, as well as sex-specific rates of eyestalk evolution. Despite this, lineages where males have been under strong sexual selection for millions of years still exhibit high levels of intersexual trait integration. This low level of decoupling between the sexes may indicate that exaggerated female eyestalks are in fact adaptive-or alternatively, that there are strong constraints on reducing trait integration between the sexes. Future work should seek to clarify the relative roles of constraints and selection in contributing to the varying levels of intersexual trait integration in stalk-eyed flies, and in this way clarify whether sexual conflicts can act as constraints on adaptive evolution even on macroevolutionary time scales.


Assuntos
Evolução Biológica , Dípteros/classificação , Caracteres Sexuais , Animais , Dípteros/anatomia & histologia , Olho/anatomia & histologia , Feminino , Masculino , Filogenia , Seleção Genética
20.
Ecol Evol ; 8(8): 4065-4073, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29721280

RESUMO

Interactions between birds and fish are often overlooked in aquatic ecosystems. We studied the influence of Atlantic salmon and brown trout on the breeding population size and reproductive output of the white-throated dipper in a Norwegian river. Acidic precipitation led to the extinction of salmon, but salmon recolonized after liming was initiated in 1991. We compared the dipper population size and reproductive output before (1978-1992) and after (1993-2014) salmon recolonization. Despite a rapid and substantial increase in juvenile salmon, the breeding dipper population size and reproductive output were not influenced by juvenile salmon, trout, or total salmonid density. This might be due to different feeding strategies in salmonids and dippers, where salmonids are mainly feeding on drift, while the dipper is a benthic feeder. The correlation between the size of the dipper population upstream and downstream of a salmonid migratory barrier was similar before and after recolonization, indicating that the downstream territories were not less attractive after the recolonization of salmon. Upstream dipper breeding success rates declined before the recolonization event and increased after, indicating improved water quality due to liming, and increasing invertebrate prey abundances and biodiversity. Surprisingly, upstream the migratory barrier, juvenile trout had a weak positive effect on the dipper population size, indicating that dippers may prey upon small trout. It is possible that wider downstream reaches might have higher abundances of alternative food, rending juvenile trout unimportant as prey. Abiotic factors such as winter temperatures and acidic precipitation with subsequent liming, potentially mediated by prey abundance, seem to play the most important role in the life history of the dipper.

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