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1.
Proc Biol Sci ; 290(1992): 20222129, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722076

RESUMO

Changing patterns in diversity are a feature of many habitats, with seasonality a major driver of ecosystem structure and function. In coastal marine plankton-based ecosystems, seasonality has been established through long-term time-series of bacterioplankton and protists. Alongside these groups, fungi also inhabit coastal marine ecosystems. If and how marine fungi show long-term intra- and inter-annual diversity patterns is unknown, preventing a comprehensive understanding of marine fungal ecology. Here, we use a 17-year environmental DNA time-series from the English Channel to determine long-term marine fungal diversity patterns. We show that fungal community structure progresses at seasonal and monthly scales and is only weakly related to environmental parameters. Communities restructured every 52-weeks suggesting long-term stability in diversity patterns. Some major marine fungal genera have clear inter-annual recurrence patterns, re-appearing in the annual cycle at the same period. Low relative abundance taxa that are likely non-marine show seasonal input to the coastal marine ecosystem suggesting land-sea exchange regularly takes place. Our results demonstrate long-term intra- and inter-annual marine fungal diversity patterns. We anticipate this study could form the basis for better understanding the ecology of marine fungi and how they fit in the structure and function of the wider coastal marine ecosystem.


Assuntos
DNA Ambiental , DNA Fúngico , Ecossistema , Ecologia , Estações do Ano , Água do Mar/microbiologia
3.
Mar Environ Res ; 184: 105855, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36610306

RESUMO

Harmful algal blooms caused by Heterocapsa bohaiensis have broken out in aquaculture areas near Liaodong Bay, China, since 2012, resulting in mass mortality of Eriocheir sinensis larvae and substantial economic loss. Chlorella pyrenoidosa is a local phytoplankton species that is found in aquaculture ponds. However, the reason why H. bohaiensis dominated and proliferated in the phytoplankton community remains unknown. Previous studies have revealed the toxicity and hemolytic activity of H. bohaiensis. It is suspected that the out-competition of H. bohaiensis to C. pyrenoidosa was associated with toxicity. Filtrate and bi-algal cultures were investigated to determine the interspecific competition between H. bohaiensis and C. pyrenoidosa in this study. Filtrate experiments revealed that H. bohaiensis showed no toxin allelopathy in C. pyrenoidosa. However, the C. pyrenoidosa filtrates had significant allelopathic effects on the growth of H. bohaiensis. The bi-algal culture experiments and the simulation showed that the dominant species were dependent on the initial cell density ratios of the species and nutrient ratios. Therefore, H. bohaiensis achieved competitive advantage through exploitation competition but not allelopathy. The results contribute to the reasons for the occurrence of H. bohaiensis blooms in a further study.


Assuntos
Chlorella , Dinoflagelados , Proliferação Nociva de Algas , Fitoplâncton , Ecologia
4.
Philos Trans R Soc Lond B Biol Sci ; 378(1872): 20210411, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36688391

RESUMO

A dynamic model and an agent-based simulation model implementing the assumptions of the confrontational scavenging hypothesis on early protolanguage as an adaptive response of Homo erectus to gradual change in their habitat has been developed and studied. The core assumptions of the hypothesis and the model scenario are the pre-adaptation of our ancestors to occupy the ecological niche that they constructed for themselves by having evolved displaced communication and a rudimentary tool manufacture, two features allowing them to use a new, concentrated and abundant resource-megafauna carrion-on the savannahs replacing arboreal habitats owing to the drying climate of East Africa at about 2 Ma. The shift in diet required coordinated cooperation by the hominin scavengers confronted with concurrent predators. Power scavenging compelled displaced symbolic communication featuring a limited semantic range; syntax was not yet required. We show that phenotypic evolution on the accuracy of information transfer between cooperating hominins is a necessary and sufficient condition for the population of agents to survive the diet shift. Both the individual and the group fitness of the hominin horde increased with the accuracy of their protolanguage, with decreasing time allocated to foraging and thus more time left for culture. This article is part of the theme issue 'Human socio-cultural evolution in light of evolutionary transitions'.


Assuntos
Evolução Biológica , Hominidae , Animais , Humanos , Ecologia , Hominidae/fisiologia , Ecossistema , Idioma , Fósseis
6.
J Helminthol ; 97: e6, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633512

RESUMO

Many of the most contentious questions that concern the ecology of helminths could be resolved with data on helminth abundance over the past few decades or centuries, but unfortunately these data are rare. A new sub-discipline - the historical ecology of parasitism - is resurrecting long-term data on the abundance of parasites, an advancement facilitated by the use of biological natural history collections. Because the world's museums hold billions of suitable specimens collected over more than a century, these potential parasitological datasets are broad in scope and finely resolved in taxonomic, temporal and spatial dimensions. Here, we set out best practices for the extraction of parasitological information from natural history collections, including how to conceive of a project, how to select specimens, how to engage curators and receive permission for proposed projects, standard operating protocols for dissections and how to manage data. Our hope is that other helminthologists will use this paper as a reference to expand their own research programmes along the dimension of time.


Assuntos
Helmintos , Parasitos , Animais , Ecologia , Museus
7.
PeerJ ; 11: e14750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700003

RESUMO

The tiger shark (Galeocerdo cuvier) has been relatively well assessed concerning biology and ecology aspects in both Atlantic and Pacific North America and in Caribbean waters. The amount of data in these regions has led to the species protection under capture quotas and with the creation of sanctuaries. The reality in developing countries, however, is the exact opposite, with scarce information on the species in the southern hemisphere, namely South American and African waters. In these regions, protection measures are insufficient, and studies on tiger shark biology and ecology are scarce, significantly hindering conservation and management efforts. Thus, the aim of this study was to compile scientific literature on the tiger shark in the South Atlantic and discuss the impact of these data (or lack thereof) distributed within a total of ten research categories for guiding management plans. In total, 41 scientific publications on different G. cuvier biology and ecology aspects were obtained. The most studied topics were Feeding Ecology (n = 12), followed by Human Interactions (n = 8), and Movements and Migration (n = 7). Northeastern Brazil (Southwest Atlantic) was the most researched area, probably due to the higher coastal abundance of tiger sharks in this area, alongside a high number of recorded attacks, justifying funding for studies in the region. No studies carried out in other South American or African countries were found. It is important to mention that even though some research topics are relatively well covered, a severe knowledge gap is noted for risk assessments and fisheries management, with a proposition for the implementation of sanctuaries noted. This is, however, particularly worrisome, as the South Atlantic is mostly unexplored in this regard for tiger sharks. It is also important to note how different the attention given to this species is in the North Atlantic when compared to the South region. Lastly, we highlight that the existence of sub-populations, the lack of migratory corridors geographically connecting distinct areas used by the species, and the lack of fisheries statistics on tiger shark landings, all increase the vulnerability of this species in the South Atlantic.


Assuntos
Ecologia , Tubarões , Animais , Humanos , Pesqueiros , Brasil , África
8.
Curr Biol ; 33(1): R36-R39, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36626863

RESUMO

Rapid movements by plants have been a subject of interest since Linnaeus in the 18th century. Largely lacking, however, has been a modern understanding of the adaptive significance of such movements. A recent study shows that rapid stamen movements can increase male fitness by scaring off pollinators once they have pollen placed on them.


Assuntos
Flores , Polinização , Pólen , Plantas , Ecologia
9.
Sci Rep ; 13(1): 907, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650168

RESUMO

Syntrophic cooperation among prokaryotes is ubiquitous and diverse. It relies on unilateral or mutual aid that may be both catalytic and metabolic in nature. Hypotheses of eukaryotic origins claim that mitochondrial endosymbiosis emerged from mutually beneficial syntrophy of archaeal and bacterial partners. However, there are no other examples of prokaryotic syntrophy leading to endosymbiosis. One potential reason is that when externalized products become public goods, they incite social conflict due to selfish mutants that may undermine any mutualistic interactions. To rigorously evaluate these arguments, here we construct a general mathematical framework of the ecology and evolution of different types of syntrophic partnerships. We do so both in a general microbial and in a eukaryogenetic context. Studying the case where partners cross-feed on each other's self-inhibiting waste, we show that cooperative partnerships will eventually dominate over selfish mutants. By contrast, systems where producers actively secrete enzymes that cross-facilitate their partners' resource consumption are not robust against cheaters over evolutionary time. We conclude that cross-facilitation is unlikely to provide an adequate syntrophic origin for endosymbiosis, but that cross-feeding mutualisms may indeed have played that role.


Assuntos
Evolução Biológica , Simbiose , Ecologia , Células Eucarióticas/metabolismo , Eucariotos
11.
PLoS One ; 18(1): e0278395, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36652426

RESUMO

Large bovids and cervids constituted major components of the European Middle Palaeolithic faunas and hence a key resource for Neanderthal populations. In paleoenvironmental reconstructions, red deer (Cervus elaphus) occurrence is classically considered as a tree-cover indicator while Bovinae (Bison priscus and Bos primigenius) and reindeer (Rangifer tarandus) occurrences are typically associated with open landscapes. However, insights into the ecology of extant ungulate populations show a more complex reality. Exploring the diet of past ungulates allows to better comprehend the hunting strategies of Palaeolithic populations and to reconstruct the modifications through time of past landscapes. By reflecting what animals have eaten during the last days or weeks of their life, dental microwear textures of herbivores link a population and its environment. Here we analyzed, via Dental Microwear Texture Analysis (DMTA), the diet of 50 Bos/Bison, 202 R. tarandus and 116 C. elaphus preyed upon by the Neanderthals that occupied Combe-Grenal rock-shelter, one of the most important Mousterian archaeo-sequences in southwestern France considering its long stratigraphy, abundance of faunal remains and the variations perceptible in Palaeolithic material culture. Grazers and mixed-feeders are the most represented dietary categories among Combe-Grenal's guild of herbivores, highlighting the availability, along the sequence, of open landscapes. The absence of clear changes in the use of plant resources by hunted ungulates through time, even though palaeoenvironmental changes were well-documented by previous studies along the sequence, is interpreted as resulting from the hunting of non-randomly selected prey by Neanderthals, preferentially in open environments. Thus, these results provide further insight into the hunting strategies of Neanderthals and modify our perception of potential links between subsistence and material culture. Combe-Grenal hunters "stayed in the open" through millennia, and were not forced to switch to hunting tactics and material technology adapted to close encounters in forested environments.


Assuntos
Bison , Cervos , Homem de Neandertal , Rena , Animais , Bovinos , França , Ecologia , Ruminantes , Fósseis
12.
Commun Biol ; 6(1): 72, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653523

RESUMO

Sedimentary DNA-based studies revealed the effects of human activity on lake cyanobacteria communities over the last centuries, yet we continue to lack information over longer timescales. Here, we apply high-resolution molecular analyses on sedimentary ancient DNA to reconstruct the history of cyanobacteria throughout the Holocene in a lake in north-eastern Germany. We find a substantial increase in cyanobacteria abundance coinciding with deforestation during the early Bronze Age around 4000 years ago, suggesting increased nutrient supply to the lake by local communities settling on the lakeshore. The next substantial human-driven increase in cyanobacteria abundance occurred only about a century ago due to intensified agricultural fertilisation which caused the dominance of potentially toxic taxa (e.g., Aphanizomenon). Our study provides evidence that humans began to locally impact lake ecology much earlier than previously assumed. Consequently, managing aquatic systems today requires awareness of the legacy of human influence dating back potentially several millennia.


Assuntos
Cianobactérias , DNA Antigo , Humanos , Lagos/microbiologia , Efeitos Antropogênicos , Cianobactérias/genética , Ecologia
13.
Curr Biol ; 33(2): R80-R82, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36693316

RESUMO

Tropical deforestation is a significant cause of global biodiversity loss. A new study shows that habitat loss may result in abrupt changes in networks of interacting species. This has major implications for the conservation and restoration of tropical forest ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Florestas , Ecologia , Biodiversidade , Clima Tropical
14.
Curr Microbiol ; 80(2): 59, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36588127

RESUMO

Serratia marcescens is a big emerging concern for human health and coral biodiversity. Spatial ecology and the influencing factors on pathogen ecology, however, remain unknown. The study forms the first global risk assessment of S. marcescens. MaxEnt niche modeling was applied using two biotic and sixteen abiotic variables. The world was classified into five risk-level categories based on the pathogen ecology, and the world population exposed to S. marcescens infection was then quantified. The prepared model showed an area under the curve value of 0.918 ± 0.028, implying excellent prediction ability. The highly and moderately suitable areas occupied around 0.52% and 17.9% of the total global land area. The order of probability of having S. marcescens-related infections was Asia > North America > South America > Europe > Africa > Australia. Human population density and temperature were the most influential factors in the distribution. The moderate to high transmission risk zones contained 0.20% (1.61 billion people) of the human population. In brief, these results give novel insights into its spatial ecology and provide the risk maps that can be utilized to plan targeted strategic control measures against future invasions of this emerging pathogen.


Assuntos
Antozoários , Serratia marcescens , Animais , Humanos , Ecologia , Ecossistema , América do Norte
15.
Science ; 379(6630): eade2109, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36701468

RESUMO

Freeman et al. (Reports, 22 July 2022, p. 416) argue that interspecific competition rather than climate is the leading driver of bird species' elevational ranges. A reanalysis of their data shows no support for the competition hypothesis, but a strong effect of climate seasonality on species ranges. Their results are artifacts arising from a suboptimal model that misses important variables.


Assuntos
Aves , Clima , Animais , Mudança Climática , Ecologia
16.
FEMS Microbiol Ecol ; 99(2)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36631293

RESUMO

Vertebrate decomposition results in an ephemeral disturbance of the surrounding environment. Microbial decomposers are recognized as key players in the breakdown of complex organic compounds, controlling carbon and nutrient fate in the ecosystem and potentially serving as indicators of time since death for forensic applications. As a result, there has been increasing attention on documenting the microbial communities associated with vertebrate decomposition, or the 'necrobiome'. These necrobiome studies differ in the vertebrate species, microhabitats (e.g. skin vs. soil), and geographic locations studied, but many are narrowly focused on the forensic application of microbial data, missing the larger opportunity to understand the ecology of these communities. To further our understanding of microbial dynamics during vertebrate decomposition and identify knowledge gaps, there is a need to assess the current works from an ecological systems perspective. In this review, we examine recent work pertaining to microbial community dynamics and succession during vertebrate (human and other mammals) decomposition in terrestrial ecosystems, through the lens of a microbial succession ecological framework. From this perspective, we describe three major microbial microhabitats (internal, external, and soil) in terms of their unique successional trajectories and identify three major knowledge gaps that remain to be addressed.


Assuntos
Ecossistema , Microbiota , Animais , Humanos , Vertebrados/metabolismo , Ecologia , Microbiologia do Solo , Solo , Mamíferos
17.
Sci Adv ; 9(2): eadd3783, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36638170

RESUMO

Microcystis, a common harmful algal bloom (HAB) taxon, threatens water supplies and human health, yet species delimitation is contentious in this taxon, leading to challenges in research and management of this threat. Historical and common morphology-based classifications recognize multiple morphospecies, most with variable and diverse ecologies, while DNA sequence-based classifications indicate a single species with multiple ecotypes. To better delimit Microcystis species, we conducted a pangenome analysis of 122 genomes. Core- and non-core gene phylogenetic analyses placed 113 genomes into 23 monophyletic clusters containing at least two genomes. Overall, genome-related indices revealed that Microcystis contains at least 16 putative genospecies. Fifteen genospecies included at least one Microcystis aeruginosa morphospecies, and 10 genospecies included two or more morphospecies. This classification system will enable consistent taxonomic identification of Microcystis and thereby aid in resolving some of the complexities and controversies that have long characterized eco-evolutionary research and management of this important HAB taxon.


Assuntos
Microcystis , Humanos , Microcystis/genética , Filogenia , Sequência de Bases , Ecologia
18.
Sci Rep ; 13(1): 1514, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707674

RESUMO

Regular and long-term monitoring of coastal areas is a prerequisite to avoiding or mitigating the impacts of climate and human-driven hazards. In Africa, where populations and infrastructures are particularly exposed to risk, there is an urgent need to establish coastal monitoring, as observations are generally scarce. Measurement campaigns and very high-resolution satellite imagery are costly, while freely available satellite observations have temporal and spatial resolutions that are not suited to capture the event scale. To address the gap, a network of low-cost, multi-variable, shore-based video camera systems has been installed along the African coasts. Here, we present this network and its principle of sharing data, methods, and results obtained, building toward the implementation of a common integrated coastal management policy between countries. Further, we list new contributions to the understanding of still poorly documented African beaches' evolution, waves, and sea level impacts. This network is a solid platform for the development of inter-disciplinary observations for resources and ecology (such as fisheries, and sargassum landing), erosion and flooding, early warning systems during extreme events, and science-based coastal infrastructure management for sustainable future coasts.


Assuntos
Efeitos Antropogênicos , Ecologia , Humanos , Inundações , Clima , Oceanos e Mares , Mudança Climática
19.
Curr Biol ; 33(2): R77-R79, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36693315

RESUMO

Higher-order interactions - the modification of interactions between a species pair by a third - remain poorly understood in nature. A new study manipulates pairwise and higher-order interactions in the field, offering exciting new insights into how higher-order interactions contribute to coexistence.


Assuntos
Ecologia , Ecossistema
20.
Ecol Lett ; 26(2): 335-346, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36604979

RESUMO

Documenting patterns of spatiotemporal change in hyper-diverse communities remains a challenge for tropical ecology yet is increasingly urgent as some long-term studies have shown major declines in bird communities in undisturbed sites. In 1982, Terborgh et al. quantified the structure and organisation of the bird community in a 97-ha. plot in southeastern Peru. We revisited the same plot in 2018 using the same methodologies as the original study to evaluate community-wide changes. Contrary to longitudinal studies of other neotropical bird communities (Tiputini, Manaus, and Panama), we found little change in community structure and organisation, with increases in 5, decreases in 2 and no change in 7 foraging guilds. This apparent stability suggests that large forest reserves such as the Manu National Park, possibly due to regional topographical influences on precipitation, still provide the conditions for establishing refugia from at least some of the effects of global change on bird communities.


Assuntos
Biodiversidade , Parques Recreativos , Animais , Florestas , Ecologia , Aves
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