1
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Frantz BH, Sepúlveda M, García‐Reyes M, Vega R, Palacios DM, Bedriñana‐Romano L, Hückstädt LA, Santos‐Carvallo M, Davis JD, Hines E. Combining potential and realized distribution modeling of telemetry data for a bycatch risk assessment. Ecol Evol 2024; 14:e11541. [PMID: 38932966 PMCID: PMC11199131 DOI: 10.1002/ece3.11541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 05/12/2024] [Accepted: 05/20/2024] [Indexed: 06/28/2024] Open
Abstract
Establishing marine species distributions is essential for guiding management and can be estimated by identifying potential favorable habitat at a population level and incorporating individual-level information (e.g., movement constraints) to inform realized space use. In this research, we applied a combined modeling approach to tracking data of adult female and juvenile South American sea lions (Otaria flavescens; n = 9) from July to November 2011 to make habitat predictions for populations in northern Chile. We incorporated topographic and oceanographic predictors with sea lion locations and environmentally based pseudo-absences in a generalized linear model for estimating population-level distribution. For the individual approach, we used a generalized linear mixed-effects model with a negative exponential kernel variable to quantify distance-dependent movement from the colony. Spatial predictions from both approaches were combined in a bivariate color map to identify areas of agreement. We then used a GIS-based risk model to characterize bycatch risk in industrial and artisanal purse-seine fisheries based on fishing set data from scientific observers and artisanal fleet logs (2010-2015), the bivariate sea lion distribution map, and criteria ratings of interaction characteristics. Our results indicate population-level associations with productive, shallow, low slope waters, near to river-mouths, and with high eddy activity. Individual distribution was restricted to shallow slopes and cool waters. Variation between approaches may reflect intrinsic factors restricting use of otherwise favorable habitat; however, sample size was limited, and additional data are needed to establish the full range of individual-level distributions. Our bycatch risk outputs identified highest risk from industrial fisheries operating nearshore (within 5 NM) and risk was lower, overall, for the artisanal fleet. This research demonstrates the potential for integrating potential and realized distribution models within a spatial risk assessment and fills a gap in knowledge on this species' distribution, providing a basis for targeting bycatch mitigation outreach and interventions.
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Affiliation(s)
- Bethany H. Frantz
- School of the EnvironmentSan Francisco State UniversitySan FranciscoCaliforniaUSA
| | - Maritza Sepúlveda
- Centro de Investigación y Gestión de Recursos Naturales (CIGREN), Instituto de Biología, Facultad de CienciasUniversidad de ValparaísoValparaísoChile
- Núcleo Milenio de Salmónidos Invasores (INVASAL)Universidad de ConcepciónConcepciónChile
| | | | - Rodrigo Vega
- Instituto de Fomento Pesquero (IFOP)ValparaísoChile
| | - Daniel M. Palacios
- Marine Mammal InstituteOregon State UniversityNewportOregonUSA
- Department of Fisheries, Wildlife and Conservation SciencesOregon State UniversityNewportOregonUSA
| | - Luis Bedriñana‐Romano
- Instituto de Ciencias Marinas y Limnológicas, Facultad de CienciasUniversidad Austral de ChileCasilla, ValdiviaChile
- NGO Centro Ballena AzulValdiviaChile
- Centro de Investigación Oceanográfica COPAS CoastalUniversidad de ConcepciónConcepciónChile
| | - Luis A. Hückstädt
- Centre for Ecology and ConservationUniversity of ExeterCornwallUK
- Institute of Marine SciencesUniversity of California Santa CruzSanta CruzCaliforniaUSA
| | - Macarena Santos‐Carvallo
- Centro de Investigación y Gestión de Recursos Naturales (CIGREN), Instituto de Biología, Facultad de CienciasUniversidad de ValparaísoValparaísoChile
| | - Jerry D. Davis
- School of the EnvironmentSan Francisco State UniversitySan FranciscoCaliforniaUSA
| | - Ellen Hines
- School of the EnvironmentSan Francisco State UniversitySan FranciscoCaliforniaUSA
- Estuary & Ocean Science CenterSan Francisco State UniversityTiburonCaliforniaUSA
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2
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Jiang X, Guo X, Lu H, Yang J, Li W, Hao Q. Distinct Community Assembly Mechanisms of Different Growth Stages in a Warm Temperate Forest. DIVERSITY 2023. [DOI: 10.3390/d15040507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
Community phylogenetic structure and diversity analysis are useful complements to species-centric approaches in biodiversity studies by providing new insights into the processes that drive community assembly. In this study, we aimed to understand the differences in the relative importance of abiotic filtering, biotic interactions, and dispersal limitation on community assembly of trees at different vegetation growth stages. We also examined the influence of geographical distance, elevation, terrain, and soil. Thus, we examined the phylogenetic structures and β-diversities of saplings and adults along different abiotic gradients. The results of the net relatedness index (NRI) showed that, instead of being random, the phylogenetic structure of saplings tended to be convergent, whereas that of adults tended to be divergent. This result implies that the relative forces of abiotic filtering and biotic interactions change throughout vegetation growth. The results of generalized dissimilarity modelling (GDM) showed that dispersal limitation (geographical distance) and abiotic filtering influenced the community assembly of both adults and saplings. This result confirmed our hypothesis that both deterministic and stochastic processes were prevalent. The explanatory rates of geographic distance and environmental factor distance to phylogenetic β-diversity were quite different between adults and saplings, which meant that the relative force of dispersal limitation and abiotic filtering had also changed.
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Affiliation(s)
- Xiaolei Jiang
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
| | - Xiao Guo
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
| | - Huicui Lu
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
| | - Jinming Yang
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
| | - Wei Li
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
| | - Qing Hao
- School of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao 266109, China
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3
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Abstract
Microbial communities can be structured by both deterministic and stochastic processes, but the relative importance of these processes remains unknown. The ambiguity partly arises from an inability to disentangle soil microbial processes from confounding factors, such as aboveground plant communities or anthropogenic disturbance. In this study, we characterized the relative contributions of determinism and stochasticity to assembly processes of soil bacterial communities across a large environmental gradient of undisturbed Antarctic soils. We hypothesized that harsh soils would impose a strong environmental selection on microbial communities, whereas communities in benign soils would be structured largely by dispersal. Contrary to our expectations, dispersal was the dominant assembly mechanism across the entire soil environmental gradient, including benign environments. The microbial community composition reflects slowly changing soil conditions and dispersal limitation of isolated sites. Thus, stochastic processes, as opposed to deterministic, are primary drivers of soil ecosystem assembly across space at our study site. This is especially surprising given the strong environmental constraints on soil microorganisms in one of the harshest environments on the planet, suggesting that dispersal could be a driving force in microbial community assembly in soils worldwide. IMPORTANCE Because of their diversity and ubiquity, microbes provide an excellent means to tease apart how natural communities are structured. In general, ecologists believe that stochastic assembly processes, like random drift and dispersal, should dominate in benign environments while deterministic processes, like environmental filtering, should be prevalent in harsh environments. To help resolve this debate, we analyzed microbial community composition in pristine Antarctic soils devoid of human influence or plant communities for eons. Our results demonstrate that dispersal limitation is a surprisingly potent force of community limitation throughout all soil conditions. Thus, dispersal appears to be a driving force of microbial community assembly, even in the harshest of conditions.
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4
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Yuan B, Guo M, Wu W, Zhou X, Li M, Xie S. Spatial and Seasonal Patterns of Sediment Bacterial Communities in Large River Cascade Reservoirs: Drivers, Assembly Processes, and Co-occurrence Relationship. MICROBIAL ECOLOGY 2023; 85:586-603. [PMID: 35338380 DOI: 10.1007/s00248-022-01999-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Sediment bacteria play an irreplaceable role in promoting the function and biogeochemical cycle of the freshwater ecosystem; however, little is known about their biogeographical patterns and community assembly mechanisms in large river suffering from cascade development. Here, we investigated the spatiotemporal distribution patterns of bacterial communities employing next-generation sequencing analysis and multivariate statistical analyses from the Lancang River cascade reservoirs during summer and winter. We found that sediment bacterial composition has a significant seasonal turnover due to the modification of cascade reservoirs operation mode, and the spatial consistency of biogeographical models (including distance-decay relationship and covariation of community composition with geographical distance) also has subtle changes. The linear regression between the dissimilarity of bacterial communities in sediments, geographical and environmental distance showed that the synergistic effects of geographical and environmental factors explained the influence on bacterial communities. Furthermore, the environmental difference explained little variations (19.40%) in community structure, implying the homogeneity of environmental conditions across the cascade reservoirs of Lancang River. From the quantification of the ecological process, the homogeneous selection was recognized as the dominating factor of bacterial community assembly. The co-occurrence topological network analyses showed that the key genera were more important than the most connected genera. In general, the assembly of bacterial communities in sediment of cascade reservoirs was mediated by both deterministic and stochastic processes and is always dominated by homogeneous selection with the seasonal switching, but the effects of dispersal limitation and ecological drift cannot be ignored.
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Affiliation(s)
- Bo Yuan
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China.
| | - Mengjing Guo
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Wei Wu
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Xiaode Zhou
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Miaojie Li
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
| | - Shuguang Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
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5
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Jewell MD, Bell G. A basic community dynamics experiment: Disentangling deterministic and stochastic processes in structuring ecological communities. Ecol Evol 2022; 12:e9568. [PMID: 36479026 PMCID: PMC9720002 DOI: 10.1002/ece3.9568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 10/25/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Community dynamics are governed by two opposed processes: species sorting, which produces deterministic dynamics leading to an equilibrium state, and ecological drift, which produces stochastic dynamics. Despite a great deal of theoretical and empirical work aiming to demonstrate the predominance of one or the other of these processes, the importance of drift in structuring communities and maintaining species diversity remains contested. Here, we present the results of a basic community dynamics experiment using floating aquatic plants, designed to measure the relative contributions of species sorting and ecological drift to community change over about a dozen generations. We found that species sorting became overwhelmingly dominant as the experiment progressed, and directed communities toward a stable equilibrium state maintained by negative frequency-dependent selection. The dynamics of any particular species depended on how far its initial frequency was from its equilibrium frequency, however, and consequently the balance of sorting and drift varied among species.
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Affiliation(s)
| | - Graham Bell
- Department of BiologyMcGill UniversityMontrealQuebecCanada,Redpath MuseumMcGill UniversityMontrealQuebecCanada
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6
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Chatterjee S, Nag Chowdhury S, Ghosh D, Hens C. Controlling species densities in structurally perturbed intransitive cycles with higher-order interactions. CHAOS (WOODBURY, N.Y.) 2022; 32:103122. [PMID: 36319275 DOI: 10.1063/5.0102599] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
The persistence of biodiversity of species is a challenging proposition in ecological communities in the face of Darwinian selection. The present article investigates beyond the pairwise competitive interactions and provides a novel perspective for understanding the influence of higher-order interactions on the evolution of social phenotypes. Our simple model yields a prosperous outlook to demonstrate the impact of perturbations on intransitive competitive higher-order interactions. Using a mathematical technique, we show how alone the perturbed interaction network can quickly determine the coexistence equilibrium of competing species instead of solving a large system of ordinary differential equations. It is possible to split the system into multiple feasible cluster states depending on the number of perturbations. Our analysis also reveals that the ratio between the unperturbed and perturbed species is inversely proportional to the amount of employed perturbation. Our results suggest that nonlinear dynamical systems and interaction topologies can be interplayed to comprehend species' coexistence under adverse conditions. Particularly, our findings signify that less competition between two species increases their abundance and outperforms others.
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Affiliation(s)
- Sourin Chatterjee
- Department of Mathematics and Statistics, Indian Institute of Science Education and Research, Kolkata, West Bengal 741246, India
| | - Sayantan Nag Chowdhury
- Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India
| | - Dibakar Ghosh
- Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India
| | - Chittaranjan Hens
- Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India
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7
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Zhao F, Yang T, Luo C, Rao W, Yang G, Li G, Shen Z. Comparing Elevational Patterns of Taxonomic, Phylogenetic, and Functional Diversity of Woody Plants Reveal the Asymmetry of Community Assembly Mechanisms on a Mountain in the Hengduan Mountains Region. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.869258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The contributions and interaction of biotic and abiotic processes in community assembly are crucial for understanding the elevational patterns of biodiversity. The combined analyses of taxonomic, phylogenetic, and functional diversity are necessary to resolve this issue. By investigating vegetation in 24 transects sampled on Hongla Snow Mountain, in the central Hengduan Mountain Ranges in Southwest China, we delineated the elevational vegetation spectrum on the eastern and western slopes, analyzed the elevational variation in taxonomic, phylogenetic, and functional diversity of woody plant species, and compared the community structure of phylogeny and function in the low-elevational shrublands, mid-elevational forests, and alpine shrubs and meadows. The species richness, phylogenetic diversity, and functional diversity of woody plants showed nonstandard hump-shaped patterns with two peaks along the elevational gradient. The community structure of phylogeny and function (including tree height, leaf area, specific leaf area, leaf thickness, bark thickness, and wood density) clustered in the low-elevation shrub communities, being random and over-dispersed in mid-elevational forests. The phylogenic structure was over-dispersed in alpine communities, whereas the functional structure was clustered. Elevational patterns in taxonomic, phylogenetic, and functional diversity, together with the mean and variation in woody plant functional traits, suggested drought stress and freeze stress as environmental filters dominating the assembly of low and high elevation non-forest communities, and a conspicuous effect of biotic facilitation was also suggested for alpine habitats. By contrast, interspecific competition dominated the community assembly of forests at mid-elevations. The difference in biodiversity indices between the west and east slopes reflected the effects of the Indian Monsoon on the geomorphic patterns of ecosystem structure. These results increased our understanding of biodiversity patterns and underlying mechanisms in the Hengduan Mountains of Southwest China and highlighted the priorities for biodiversity conservation in this region.
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8
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Takeuchi Y, Ohtsuki H, Innan H. Non-zero-sum neutrality test for the tropical rain forest community using long-term between-census data. Ecol Evol 2022; 12:e8462. [PMID: 35136547 PMCID: PMC8809451 DOI: 10.1002/ece3.8462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 11/01/2021] [Accepted: 11/12/2021] [Indexed: 11/07/2022] Open
Abstract
For community ecologists, "neutral or not?" is a fundamental question, and thus, rejecting neutrality is an important first step before investigating the deterministic processes underlying community dynamics. Hubbell's neutral model is an important contribution to the exploration of community dynamics, both technically and philosophically. However, the neutrality tests for this model are limited by a lack of statistical power, partly because the zero-sum assumption of the model is unrealistic. In this study, we developed a neutrality test for local communities that implements non-zero-sum community dynamics and determines the number of new species (N sp) between observations. For the non-zero-sum neutrality test, the model distributed the expected N sp, as calculated by extensive simulations, which allowed us to investigate the neutrality of the observed community by comparing the observed N sp with distributions of the expected N sp derived from the simulations. For this comparison, we developed a new "non-zero-sum N sp test," which we validated by running multiple neutral simulations using different parameter settings. We found that the non-zero-sum N sp test rejected neutrality at a near-significance level, which justified the validity of our approach. For an empirical test, the non-zero-sum N sp test was applied to real tropical tree communities in Panama and Malaysia. The non-zero-sum N sp test rejected neutrality in both communities when the observation interval was long and N sp was large. Hence, the non-zero-sum N sp test is an effective way to examine neutrality and has reasonable statistical power to reject the neutral model, especially when the observed N sp is large. This unique and simple approach is statistically powerful, even though it only employs two temporal sequences of community data. Thus, this test can be easily applied to existing datasets. In addition, application of the test will provide significant benefits for detecting changing biodiversity under climate change and anthropogenic disturbance.
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Affiliation(s)
- Yayoi Takeuchi
- Biodiversity Division National Institute for Environmental Studies Tsukuba Japan
| | - Hisashi Ohtsuki
- SOKENDAI (The Graduate University for Advanced Studies) Hayama Japan
| | - Hideki Innan
- SOKENDAI (The Graduate University for Advanced Studies) Hayama Japan
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9
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Philosophical Skepticism Concerning the Neutral Theory or Randomness: Misplaced or Misconceived? A Reply to Madison, "Stochasticity and Randomness in Community Assembly: Real or As-If?". mSystems 2021; 6:e0101421. [PMID: 34491086 PMCID: PMC8547475 DOI: 10.1128/msystems.01014-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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10
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Ordaz-Németh I, Sop T, Amarasekaran B, Bachmann M, Boesch C, Brncic T, Caillaud D, Campbell G, Carvalho J, Chancellor R, Davenport TRB, Dowd D, Eno-Nku M, Ganas-Swaray J, Granier N, Greengrass E, Heinicke S, Herbinger I, Inkamba-Nkulu C, Iyenguet F, Junker J, Bobo KS, Lushimba A, Maisels F, Malanda GAF, McCarthy MS, Motsaba P, Moustgaard J, Murai M, Ndokoue B, Nixon S, Nseme RA, Nzooh Z, Pintea L, Plumptre AJ, Roy J, Rundus A, Sanderson J, Serckx A, Strindberg S, Tweh C, Vanleeuwe H, Vosper A, Waltert M, Williamson EA, Wilson M, Mundry R, Kühl HS. Range-wide indicators of African great ape density distribution. Am J Primatol 2021; 83:e23338. [PMID: 34662462 DOI: 10.1002/ajp.23338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/05/2021] [Accepted: 09/30/2021] [Indexed: 01/23/2023]
Abstract
Species distributions are influenced by processes occurring at multiple spatial scales. It is therefore insufficient to model species distribution at a single geographic scale, as this does not provide the necessary understanding of determining factors. Instead, multiple approaches are needed, each differing in spatial extent, grain, and research objective. Here, we present the first attempt to model continent-wide great ape density distribution. We used site-level estimates of African great ape abundance to (1) identify socioeconomic and environmental factors that drive densities at the continental scale, and (2) predict range-wide great ape density. We collated great ape abundance estimates from 156 sites and defined 134 pseudo-absence sites to represent additional absence locations. The latter were based on locations of unsuitable environmental conditions for great apes, and on existing literature. We compiled seven socioeconomic and environmental covariate layers and fitted a generalized linear model to investigate their influence on great ape abundance. We used an Akaike-weighted average of full and subset models to predict the range-wide density distribution of African great apes for the year 2015. Great ape densities were lowest where there were high Human Footprint and Gross Domestic Product values; the highest predicted densities were in Central Africa, and the lowest in West Africa. Only 10.7% of the total predicted population was found in the International Union for Conservation of Nature Category I and II protected areas. For 16 out of 20 countries, our estimated abundances were largely in line with those from previous studies. For four countries, Central African Republic, Democratic Republic of the Congo, Liberia, and South Sudan, the estimated populations were excessively high. We propose further improvements to the model to overcome survey and predictor data limitations, which would enable a temporally dynamic approach for monitoring great apes across their range based on key indicators.
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Affiliation(s)
- Isabel Ordaz-Németh
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Tenekwetche Sop
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Mona Bachmann
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Christophe Boesch
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Wild Chimpanzee Foundation, Leipzig, Germany
| | - Terry Brncic
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | - Damien Caillaud
- Dian Fossey Gorilla Fund International, Atlanta, USA.,Department of Anthropology, University of California, Davis, California, USA
| | | | - Joana Carvalho
- Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, UK
| | - Rebecca Chancellor
- Departments of Anthropology & Sociology and Psychology, West Chester University, West Chester, Pennsylvania, USA
| | - Tim R B Davenport
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | - Dervla Dowd
- Wild Chimpanzee Foundation, Leipzig, Germany
| | | | | | | | | | - Stefanie Heinicke
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany.,Transformation Pathways Research Department, Potsdam Institute for Climate Impact Research, Potsdam, Germany
| | | | | | - Fortuné Iyenguet
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | - Jessica Junker
- Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany
| | - Kadiri S Bobo
- Department of Forestry, Faculty of Agronomy and Agricultural Sciences, The University of Dschang, Dschang, Cameroon
| | - Alain Lushimba
- IUCN, Regional Program Central and West Africa, Ouagadougou, Burkina Faso
| | - Fiona Maisels
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA.,Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, UK
| | | | - Maureen S McCarthy
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Prosper Motsaba
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | | | - Mizuki Murai
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Bezangoye Ndokoue
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | | | | | | | - Lilian Pintea
- Conservation Science, Jane Goodall Institute, Vienna, USA
| | | | - Justin Roy
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Aaron Rundus
- Department of Psychology, West Chester University, West Chester, Pennsylvania, USA
| | - Jim Sanderson
- Small Wild Cat Conservation Foundation, Corrales, New Mexico, USA
| | - Adeline Serckx
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,The Biodiversity Consultancy Ltd., Cambridge, UK.,Behavioral Biology Unit, Primatology Research Group, University of Liège, Liège, Belgium
| | - Samantha Strindberg
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | - Clement Tweh
- Wild Chimpanzee Foundation, Leipzig, Germany.,School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - Hilde Vanleeuwe
- Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
| | | | - Matthias Waltert
- Workgroup on Endangered Species, University of Göttingen, Göttingen, Germany
| | | | - Michael Wilson
- Departments of Anthropology and Ecology, Evolution and Behavior, University of Minnesota, Minneapolis, Minnesota, USA
| | - Roger Mundry
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Hjalmar S Kühl
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany
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11
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Peck SL, Heiss A. Can constraint closure provide a generalized understanding of community dynamics in ecosystems? OIKOS 2021. [DOI: 10.1111/oik.07621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Andrew Heiss
- Dept of Public Management and Policy/Andrew Young School of Policy Studies, Georgia State Univ. Atlanta GA USA
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12
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Phylogenetic and Functional Traits Verify the Combined Effect of Deterministic and Stochastic Processes in the Community Assembly of Temperate Forests along an Elevational Gradient. FORESTS 2021. [DOI: 10.3390/f12050591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Explaining community assembly mechanisms along elevational gradients dominated by deterministic processes or stochastic processes is a pressing challenge. Many studies suggest that phylogenetic and functional diversity are significant indicators of the process. In this study, we analyzed the structure and beta diversity of phylogenetic and functional traits along an elevational gradient and discussed the effects of environmental and spatial factors. We found that the phylogenetic and functional traits showed inconsistent changes, and their variations were closely related to the abiotic environment. The results suggested that the community assembly of woody plants was obviously affected by the combined effect of deterministic processes and the stochastic hypothesis (primarily by the latter). Phylogenetic and functional traits had a certain relationship but changed according to different rules. These results enhance our understanding of the assembly mechanism of forest communities by considering both phylogenetic and functional traits.
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13
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Travassos‐Britto B, Pardini R, El‐Hani CN, Prado PI. Towards a pragmatic view of theories in ecology. OIKOS 2021. [DOI: 10.1111/oik.07314] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Charbel N. El‐Hani
- Centre for Social Studies, Univ. of Coimbra Coimbra Portugal
- Inst. of Biology, Federal Univ. of Bahia Salvador BA Brazil
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14
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van Eldijk TJB, Bisschop K, Etienne RS. Uniting Community Ecology and Evolutionary Rescue Theory: Community-Wide Rescue Leads to a Rapid Loss of Rare Species. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.552268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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15
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Deines P, Hammerschmidt K, Bosch TCG. Exploring the Niche Concept in a Simple Metaorganism. Front Microbiol 2020; 11:1942. [PMID: 32849483 PMCID: PMC7432292 DOI: 10.3389/fmicb.2020.01942] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 07/23/2020] [Indexed: 11/30/2022] Open
Abstract
Organisms and their resident microbial communities - the microbiome - form a complex and mostly stable ecosystem. It is known that the composition of the microbiome and bacterial species abundances can have a major impact on host health and Darwinian fitness, but the processes that lead to these microbial patterns have not yet been identified. We here apply the niche concept and trait-based approaches as a first step in understanding the patterns underlying microbial community assembly and structure in the simple metaorganism Hydra. We find that the carrying capacities in single associations do not reflect microbiota densities as part of the community, indicating a discrepancy between the fundamental and realized niche. Whereas in most cases, the realized niche is smaller than the fundamental one, as predicted by theory, the opposite is observed for Hydra’s two main bacterial colonizers. Both, Curvibacter sp. and Duganella sp. benefit from association with the other members of the microbiome and reach higher fractions as compared to when they are the only colonizer. This cannot be linked to any particular trait that is relevant for interacting with the host or by the utilization of specific nutrients but is most likely determined by metabolic interactions between the individual microbiome members.
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Affiliation(s)
- Peter Deines
- Zoological Institute, Christian Albrechts University Kiel, Kiel, Germany
| | - Katrin Hammerschmidt
- Institute of General Microbiology, Christian Albrechts University Kiel, Kiel, Germany
| | - Thomas C G Bosch
- Zoological Institute, Christian Albrechts University Kiel, Kiel, Germany
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16
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Abstract
Neutral models of evolution assume the absence of natural selection. Formerly confined to ecology and evolutionary biology, neutral models are spreading. In recent years they've been applied to explaining the diversity of baby names, scientific citations, cryptocurrencies, pot decorations, literary lexica, tumour variants and much more besides. Here, we survey important neutral models and highlight their similarities. We investigate the most widely used tests of neutrality, show that they are weak and suggest more powerful methods. We conclude by discussing the role of neutral models in the explanation of diversity. We suggest that the ability of neutral models to fit low-information distributions should not be taken as evidence for the absence of selection. Nevertheless, many studies, in increasingly diverse fields, make just such claims. We call this tendency 'neutral syndrome'.
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17
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Li Y, Gao Y, Zhang W, Wang C, Wang P, Niu L, Wu H. Homogeneous selection dominates the microbial community assembly in the sediment of the Three Gorges Reservoir. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 690:50-60. [PMID: 31284194 DOI: 10.1016/j.scitotenv.2019.07.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 06/28/2019] [Accepted: 07/01/2019] [Indexed: 06/09/2023]
Abstract
Deep-water reservoir sediment is a unique habitat sheltering indispensable microorganisms and facilitating their biogeochemical functions; however, the assembly processes of the microbial community therein remain elusive. This study focuses on the assembly processes in the Three Gorges Reservoir Area (TGRA). A total of 42 sediment samples were collected from the TGRA, both in the mainstream and the tributaries, and in different seasons. Metagenomic analyses of 16S rRNA using Exact Sequence Variants revealed the spatiotemporal distribution patterns of the microbial communities. Linear regressions between dissimilarity of microbial communities, geographic and environmental distance showed that environmental, rather than geographic factors, impacted the microbial community. However, the environmental differences explained little variations (14.14%) in community structure, implying the homogeneity of environmental conditions across the TGRA. From the quantification of ecological processes, homogeneous selection was shown to be a dominating factor (51.34%) in the assembly of the microbial communities. The co-occurrence network showed that keystone species were more important than prevalent abundant species in interspecies interactions. Overall, the assembly of microbial community in the deep-water reservoir sediment is mediated by both deterministic and stochastic processes, and homogeneous selection plays a leading role.
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Affiliation(s)
- Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Yu Gao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
| | - Hainan Wu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China
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18
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Fung T, Verma S, Chisholm RA. Probability distributions of extinction times, species richness, and immigration and extinction rates in neutral ecological models. J Theor Biol 2019; 485:110051. [PMID: 31626812 DOI: 10.1016/j.jtbi.2019.110051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 10/07/2019] [Accepted: 10/14/2019] [Indexed: 01/30/2023]
Abstract
In community ecology, neutral models make the assumption that species are equivalent, such that species abundances differ only because of demographic stochasticity. Despite their ecological simplicity, neutral models have been found to give reasonable descriptions of expected patterns of biodiversity in communities with many species. Such patterns include the expected total number of species and species-abundance distributions describing the expected number of species in different abundance classes. However, the expected patterns represent only the central tendencies of the full distributions of possible outcomes. Thus, ecological inferences and conclusions based only on expected patterns are incomplete, and may be misleading. Here, we address this issue for the spatially implicit neutral model, by using classic results from birth-death processes to derive (1) the probability distribution of extinction time of a species with given abundance for the metacommunity; (2) the probability distributions of total species richness and number of species with given abundance for both the metacommunity and local community; and (3) the probability distributions of the average immigration and extinction rates in the local community, across different values of total species richness. We illustrate the utility of these probability distributions in providing greater ecological insight via statistical inference. Firstly, we show that under the neutral metacommunity model, there is only 2.65×10-9 probability that the age of a common tree species in the Amazon is ≤ 3 × 108 yr, which is approximately the oldest estimated age of the first angiosperm. Thus, species ages from the model are unrealistically high. Secondly, for a tree community in a 50 ha plot at Barro Colorado Island in Panama, we show that the spatially implicit model can be fitted to observed species richness and an independent estimate of the immigration parameter, with the fitted model predicting a species-abundance distribution close to the observed distribution. Our results complement those using sampling formulae that specify the multivariate probability distribution of species abundances from neutral models.
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Affiliation(s)
- Tak Fung
- National University of Singapore, Department of Biological Sciences, 16 Science Drive 4, Singapore 117558, Singapore.
| | - Sonali Verma
- Scuola Normale Superiore, Department of Physics, Piazza dei Cavalieri, Pisa 7-56126, Italy.
| | - Ryan A Chisholm
- National University of Singapore, Department of Biological Sciences, 16 Science Drive 4, Singapore 117558, Singapore.
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19
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Bongalov B, Burslem DFRP, Jucker T, Thompson SED, Rosindell J, Swinfield T, Nilus R, Clewley D, Phillips OL, Coomes DA. Reconciling the contribution of environmental and stochastic structuring of tropical forest diversity through the lens of imaging spectroscopy. Ecol Lett 2019; 22:1608-1619. [PMID: 31347263 PMCID: PMC6852337 DOI: 10.1111/ele.13357] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/08/2019] [Accepted: 07/01/2019] [Indexed: 11/29/2022]
Abstract
Both niche and stochastic dispersal processes structure the extraordinary diversity of tropical plants, but determining their relative contributions has proven challenging. We address this question using airborne imaging spectroscopy to estimate canopy β-diversity for an extensive region of a Bornean rainforest and challenge these data with models incorporating niches and dispersal. We show that remotely sensed and field-derived estimates of pairwise dissimilarity in community composition are closely matched, proving the applicability of imaging spectroscopy to provide β-diversity data for entire landscapes of over 1000 ha containing contrasting forest types. Our model reproduces the empirical data well and shows that the ecological processes maintaining tropical forest diversity are scale dependent. Patterns of β-diversity are shaped by stochastic dispersal processes acting locally whilst environmental processes act over a wider range of scales.
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Affiliation(s)
- Boris Bongalov
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - David F R P Burslem
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, UK
| | - Tommaso Jucker
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.,School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Samuel E D Thompson
- Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.,National University of Singapore, 21 Lower Kent Ridge Road, 119077, Singapore
| | - James Rosindell
- Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK
| | - Tom Swinfield
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.,Centre for Conservation Science, Royal Society for Protection of Birds, David Attenborough Building, Cambridge, CB2 3QZ, UK
| | - Reuben Nilus
- Forest Research Centre, Sabah Forestry Department, Sandakan, Malaysia
| | | | | | - David A Coomes
- Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
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20
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Fung T, Xiao S, Chisholm RA. Spatial scaling of species richness–productivity relationships for local communities: analytical results from a neutral model. THEOR ECOL-NETH 2019. [DOI: 10.1007/s12080-019-0431-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Dynamics and Functional Potential of Stormwater Microorganisms Colonizing Sand Filters. WATER 2018. [DOI: 10.3390/w10081065] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Stormwater management is increasingly relying on engineered infiltration systems (EIS) to reduce the volume and improve the quality of managed stormwater. Yet, EIS in the field will be colonized by a diverse array of environmental microorganisms that change the physiochemical properties of the EIS and provide a habitat for microorganisms with harmful or beneficial qualities. Understanding factors influencing the composition and stability of microbial communities could open up strategies for more efficient management of stormwater. Here, we analyzed the potential pathogenic and metabolic capabilities of stormwater microorganisms colonizing idealized EIS (i.e., sand columns) under laboratory conditions over time. The diversity of microbial communities was analyzed using 16S rRNA gene sequencing, and potential pathogens and denitrifying microbes were identified from taxonomic match to known species. Denitrification potential as determined by nosZ abundance was also assessed with quantitative polymerase chain reaction PCR. Our findings demonstrate that replicate microbial communities colonizing sand columns change in a similar way over time, distinct from control columns and the source community. Potential pathogens were initially more abundant on the columns than in the stormwater but returned to background levels by 24 days after inoculation. The conditions within sand columns select for potential denitrifying microorganisms, some of which were also potential pathogens. These results demonstrate that a diverse suite of stormwater microorganisms colonize sand filters, including a transient population of potential pathogens and denitrifiers. Manipulating the inoculating microbial community of EIS could prove an effective mechanism for changing both potential pathogens and denitrifying bacteria.
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22
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Aduse‐Poku K, Molleman F, Oduro W, Oppong SK, Lohman DJ, Etienne RS. Relative contribution of neutral and deterministic processes in shaping fruit-feeding butterfly assemblages in Afrotropical forests. Ecol Evol 2018; 8:296-308. [PMID: 29321872 PMCID: PMC5756852 DOI: 10.1002/ece3.3618] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 10/03/2017] [Accepted: 10/08/2017] [Indexed: 11/13/2022] Open
Abstract
The unified neutral theory of biodiversity and biogeography has gained the status of a quantitative null model for explaining patterns in ecological (meta)communities. The theory assumes that individuals of trophically similar species are functionally equivalent. We empirically evaluate the relative contribution of neutral and deterministic processes in shaping fruit-feeding butterfly assemblages in three tropical forests in Africa, using both direct (confronting the neutral model with species abundance data) and indirect approaches (testing the predictions of neutral theory using data other than species abundance distributions). Abundance data were obtained by sampling butterflies using banana baited traps set at the forest canopy and understorey strata. Our results indicate a clear consistency in the kind of species or species groups observed at either the canopy or understorey in the three studied communities. Furthermore, we found significant correlation between some flight-related morphological traits and species abundance at the forest canopy, but not at the understorey. Neutral theory's contribution to explaining our data lies largely in identifying dispersal limitation as a key process regulating fruit-feeding butterfly community structure. Our study illustrates that using species abundance data alone in evaluating neutral theory can be informative, but is insufficient. Species-level information such as habitat preference, host plants, geographical distribution, and phylogeny is essential in elucidating the processes that regulate biodiversity community structures and patterns.
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Affiliation(s)
- Kwaku Aduse‐Poku
- Biology DepartmentCity College of New YorkCity University of New YorkNew YorkNYUSA
- School of Natural ResourcesUniversity of Energy and Natural ResourcesSunyaniGhana
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Freerk Molleman
- Centre for Research and Education in Ecology and EvolutionIndian Institute of Science Education and Research Thiruvananthapuram (IISER‐TVM)ThiruvananthapuramKeralaIndia
- Department of Systematic Zoology. Ecology Institute of Environmental BiologyFaculty of BiologyA. Mickiewicz UniversityPoznańPoland
| | - William Oduro
- FRNR‐College of Agricultural and Renewable Natural ResourcesKwame Nkrumah University of Science & TechnologyKumasiGhana
| | - Samuel K. Oppong
- FRNR‐College of Agricultural and Renewable Natural ResourcesKwame Nkrumah University of Science & TechnologyKumasiGhana
| | - David J. Lohman
- Biology DepartmentCity College of New YorkCity University of New YorkNew YorkNYUSA
- Biology Ph.D. Program, Graduate CenterCity University of New YorkNew YorkNYUSA
- Entomology SectionNational Museum of the PhilippinesManilaPhilippines
| | - Rampal S. Etienne
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
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23
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Climate and dispersal influence the structure of leaf fungal endophyte communities of Quercus gambelii in the eastern Great Basin, USA. FUNGAL ECOL 2017. [DOI: 10.1016/j.funeco.2017.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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24
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Bispo PDC, Balzter H, Malhi Y, Slik JWF, dos Santos JR, Rennó CD, Espírito-Santo FD, Aragão LEOC, Ximenes AC, Bispo PDC. Drivers of metacommunity structure diverge for common and rare Amazonian tree species. PLoS One 2017; 12:e0188300. [PMID: 29155865 PMCID: PMC5695845 DOI: 10.1371/journal.pone.0188300] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 11/04/2017] [Indexed: 11/19/2022] Open
Abstract
We analysed the flora of 46 forest inventory plots (25 m x 100 m) in old growth forests from the Amazonian region to identify the role of environmental (topographic) and spatial variables (obtained using PCNM, Principal Coordinates of Neighbourhood Matrix analysis) for common and rare species. For the analyses, we used multiple partial regression to partition the specific effects of the topographic and spatial variables on the univariate data (standardised richness, total abundance and total biomass) and partial RDA (Redundancy Analysis) to partition these effects on composition (multivariate data) based on incidence, abundance and biomass. The different attributes (richness, abundance, biomass and composition based on incidence, abundance and biomass) used to study this metacommunity responded differently to environmental and spatial processes. Considering standardised richness, total abundance (univariate) and composition based on biomass, the results for common species differed from those obtained for all species. On the other hand, for total biomass (univariate) and for compositions based on incidence and abundance, there was a correspondence between the data obtained for the total community and for common species. Our data also show that in general, environmental and/or spatial components are important to explain the variability in tree communities for total and common species. However, with the exception of the total abundance, the environmental and spatial variables measured were insufficient to explain the attributes of the communities of rare species. These results indicate that predicting the attributes of rare tree species communities based on environmental and spatial variables is a substantial challenge. As the spatial component was relevant for several community attributes, our results demonstrate the importance of using a metacommunities approach when attempting to understand the main ecological processes underlying the diversity of tropical forest communities.
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Affiliation(s)
- Polyanna da Conceição Bispo
- Leicester Institute for Space and Earth Observation, Centre for Landscape and Climate Research, Department of Geography, University of Leicester, Leicester, United Kingdom
- NERC, National Centre for Earth Observation at the University of Leicester, Leicester, United Kingdom
- * E-mail:
| | - Heiko Balzter
- Leicester Institute for Space and Earth Observation, Centre for Landscape and Climate Research, Department of Geography, University of Leicester, Leicester, United Kingdom
- NERC, National Centre for Earth Observation at the University of Leicester, Leicester, United Kingdom
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - J. W. Ferry Slik
- Faculty of Science, Universiti Brunei Darussalam, Gadong, Brunei
| | - João Roberto dos Santos
- Remote Sensing Division, National Institute for Space Research (INPE), São José dos Campos, Brazil
| | - Camilo Daleles Rennó
- Image Processing Division, National Institute for Space Research (INPE), São José dos Campos, Brazil
| | | | - Luiz E. O. C. Aragão
- Remote Sensing Division, National Institute for Space Research (INPE), São José dos Campos, Brazil
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Arimatéa C. Ximenes
- Laboratory of Systems Ecology and Resource Management, Department of Biology of Organisms, Université Libre de Bruxelles, Brussels, Belgium
- Laboratory of Plant Biology and Nature Management, Ecology & Biodiversity, Vrije Universiteit Brussel, Brussels, Belgium
| | - Pitágoras da Conceição Bispo
- Department of Biological Sciences, Faculty of Sciences and Languages of Assis, State University of São Paulo (UNESP), Assis, Brazil
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25
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Bonnet-Lebrun AS, Manica A, Eriksson A, Rodrigues ASL. Empirical phylogenies and species abundance distributions are consistent with preequilibrium dynamics of neutral community models with gene flow. Evolution 2017; 71:1149-1163. [PMID: 28306137 DOI: 10.1111/evo.13228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 03/04/2017] [Indexed: 11/30/2022]
Abstract
Community characteristics reflect past ecological and evolutionary dynamics. Here, we investigate whether it is possible to obtain realistically shaped modeled communities-that is with phylogenetic trees and species abundance distributions shaped similarly to typical empirical bird and mammal communities-from neutral community models. To test the effect of gene flow, we contrasted two spatially explicit individual-based neutral models: one with protracted speciation, delayed by gene flow, and one with point mutation speciation, unaffected by gene flow. The former produced more realistic communities (shape of phylogenetic tree and species-abundance distribution), consistent with gene flow being a key process in macro-evolutionary dynamics. Earlier models struggled to capture the empirically observed branching tempo in phylogenetic trees, as measured by the gamma statistic. We show that the low gamma values typical of empirical trees can be obtained in models with protracted speciation, in preequilibrium communities developing from an initially abundant and widespread species. This was even more so in communities sampled incompletely, particularly if the unknown species are the youngest. Overall, our results demonstrate that the characteristics of empirical communities that we have studied can, to a large extent, be explained through a purely neutral model under preequilibrium conditions.
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Affiliation(s)
- Anne-Sophie Bonnet-Lebrun
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valéry Montpellier-EPHE, 1919 route de Mende, 34293 Montpellier cedex 5, France.,Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom.,École Normale Supérieure, 45 rue d'Ulm, F-75230, Paris, France
| | - Andrea Manica
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom
| | - Anders Eriksson
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom.,Integrative Systems Biology Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Ana S L Rodrigues
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valéry Montpellier-EPHE, 1919 route de Mende, 34293 Montpellier cedex 5, France
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26
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Janzen T, Alzate A, Muschick M, Maan ME, van der Plas F, Etienne RS. Community assembly in Lake Tanganyika cichlid fish: quantifying the contributions of both niche-based and neutral processes. Ecol Evol 2017; 7:1057-1067. [PMID: 28303177 PMCID: PMC5306054 DOI: 10.1002/ece3.2689] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/07/2016] [Accepted: 11/27/2016] [Indexed: 02/03/2023] Open
Abstract
The cichlid family features some of the most spectacular examples of adaptive radiation. Evolutionary studies have highlighted the importance of both trophic adaptation and sexual selection in cichlid speciation. However, it is poorly understood what processes drive the composition and diversity of local cichlid species assemblages on relatively short, ecological timescales. Here, we investigate the relative importance of niche-based and neutral processes in determining the composition and diversity of cichlid communities inhabiting various environmental conditions in the littoral zone of Lake Tanganyika, Zambia. We collected data on cichlid abundance, morphometrics, and local environments. We analyzed relationships between mean trait values, community composition, and environmental variation, and used a recently developed modeling technique (STEPCAM) to estimate the contributions of niche-based and neutral processes to community assembly. Contrary to our expectations, our results show that stochastic processes, and not niche-based processes, were responsible for the majority of cichlid community assembly. We also found that the relative importance of niche-based and neutral processes was constant across environments. However, we found significant relationships between environmental variation, community trait means, and community composition. These relationships were caused by niche-based processes, as they disappeared in simulated, purely neutrally assembled communities. Importantly, these results can potentially reconcile seemingly contrasting findings in the literature about the importance of either niche-based or neutral-based processes in community assembly, as we show that significant trait relationships can already be found in nearly (but not completely) neutrally assembled communities; that is, even a small deviation from neutrality can have major effects on community patterns.
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Affiliation(s)
- Thijs Janzen
- Department of Evolutionary TheoryMax Planck Institute for Evolutionary BiologyPlönGermany
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Adriana Alzate
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
- Terrestrial Ecology UnitUniversity of GhentGhentBelgium
- Fundacion EcomaresCaliColombia
| | - Moritz Muschick
- Zoological InstituteUniversity of BaselBaselSwitzerland
- Department of Fish Ecology & EvolutionEAWAG Centre for EcologyKastanienbaumSwitzerland
| | - Martine E. Maan
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
| | - Fons van der Plas
- Institute of Plant SciencesUniversity of BernBernSwitzerland
- Biodiversity and Climate Research CentreSenckenberg Gesellschaft für NaturforschungFrankfurtGermany
| | - Rampal S. Etienne
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenGroningenThe Netherlands
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27
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28
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Munoz F, Huneman P. From the Neutral Theory to a Comprehensive and Multiscale Theory of Ecological Equivalence. QUARTERLY REVIEW OF BIOLOGY 2016; 91:321-42. [DOI: 10.1086/688098] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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29
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Linquist S, Cottenie K, Elliott TA, Saylor B, Kremer SC, Gregory TR. Applying ecological models to communities of genetic elements: the case of neutral theory. Mol Ecol 2015; 24:3232-42. [DOI: 10.1111/mec.13219] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 04/23/2015] [Accepted: 04/24/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Stefan Linquist
- Department of Philosophy; University of Guelph; Guelph Ontario Canada N1G 2W1
| | - Karl Cottenie
- Department of Integrative Biology; University of Guelph; Guelph Ontario Canada N1G 2W1
| | - Tyler A. Elliott
- Department of Integrative Biology; University of Guelph; Guelph Ontario Canada N1G 2W1
| | - Brent Saylor
- Department of Integrative Biology; University of Guelph; Guelph Ontario Canada N1G 2W1
| | - Stefan C. Kremer
- School of Computer Science; University of Guelph; Guelph Ontario Canada N1G 2W1
| | - T. Ryan Gregory
- Department of Integrative Biology; University of Guelph; Guelph Ontario Canada N1G 2W1
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30
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Janzen T, Haegeman B, Etienne RS. A sampling formula for ecological communities with multiple dispersal syndromes. J Theor Biol 2015; 374:94-106. [PMID: 25816742 DOI: 10.1016/j.jtbi.2015.03.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 03/10/2015] [Accepted: 03/13/2015] [Indexed: 10/23/2022]
Abstract
Over the past decade, the neutral theory of biodiversity has stirred up community assembly theory considerably by suggesting that stochasticity in the form of ecological drift is an important factor determining community composition and community turnover. The neutral theory assumes that all species within a community are functionally equivalent (the neutrality assumption), and therefore applies best to communities of trophically similar species. Evidently, trophically similar species may still differ in dispersal ability, and therefore may not be completely functionally equivalent. Here we present a new sampling formula that takes into account the partitioning of a community into two guilds that differ in immigration rate. We show that, using this sampling formula, we can accurately detect a subdivision into guilds from species abundance distributions, given ecological data about dispersal ability. We apply our sampling formula to tropical tree data from Barro Colorado Island, Panama. Tropical trees are divided depending on their dispersal mode, where biotically dispersed trees are grouped as one guild, and abiotically dispersed trees represent another guild. We find that breaking neutrality by adding guild structure to the neutral model significantly improves the fit to data and provides a better understanding of community assembly on BCI. Our findings are thus an important step towards an integration of neutral and niche theory.
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Affiliation(s)
- Thijs Janzen
- University of Groningen, Groningen Institute for Evolutionary Life Sciences, Box 11103, 9700 CC Groningen, The Netherlands.
| | - Bart Haegeman
- Centre for Biodiversity Theory and Modelling, Station d׳Ecologie Expérimentale du CNRS, 2 route du CNRS, 09200 Moulis, France
| | - Rampal S Etienne
- University of Groningen, Groningen Institute for Evolutionary Life Sciences, Box 11103, 9700 CC Groningen, The Netherlands
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Al Hammal O, Alonso D, Etienne RS, Cornell SJ. When can species abundance data reveal non-neutrality? PLoS Comput Biol 2015; 11:e1004134. [PMID: 25793889 PMCID: PMC4368519 DOI: 10.1371/journal.pcbi.1004134] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 01/16/2015] [Indexed: 11/19/2022] Open
Abstract
Species abundance distributions (SAD) are probably ecology's most well-known empirical pattern, and over the last decades many models have been proposed to explain their shape. There is no consensus over which model is correct, because the degree to which different processes can be discerned from SAD patterns has not yet been rigorously quantified. We present a power calculation to quantify our ability to detect deviations from neutrality using species abundance data. We study non-neutral stochastic community models, and show that the presence of non-neutral processes is detectable if sample size is large enough and/or the amplitude of the effect is strong enough. Our framework can be used for any candidate community model that can be simulated on a computer, and determines both the sampling effort required to distinguish between alternative processes, and a range for the strength of non-neutral processes in communities whose patterns are statistically consistent with neutral theory. We find that even data sets of the scale of the 50 Ha forest plot on Barro Colorado Island, Panama, are unlikely to be large enough to detect deviations from neutrality caused by competitive interactions alone, though the presence of multiple non-neutral processes with contrasting effects on abundance distributions may be detectable.
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Affiliation(s)
- Omar Al Hammal
- School of Biology, University of Leeds, Leeds, United Kingdom
| | - David Alonso
- School of Biology, University of Leeds, Leeds, United Kingdom
- Center for Advanced Studies (CEAB-CSIC), Blanes, Spain
| | - Rampal S. Etienne
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
| | - Stephen J. Cornell
- School of Biology, University of Leeds, Leeds, United Kingdom
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom (current address)
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Application of a neutral community model to assess structuring of the human lung microbiome. mBio 2015. [PMID: 25604788 DOI: 10.1128/mbio.02 284-14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED DNA from phylogenetically diverse microbes is routinely recovered from healthy human lungs and used to define the lung microbiome. The proportion of this DNA originating from microbes adapted to the lungs, as opposed to microbes dispersing to the lungs from other body sites and the atmosphere, is not known. We use a neutral model of community ecology to distinguish members of the lung microbiome whose presence is consistent with dispersal from other body sites and those that deviate from the model, suggesting a competitive advantage to these microbes in the lungs. We find that the composition of the healthy lung microbiome is consistent with predictions of the neutral model, reflecting the overriding role of dispersal of microbes from the oral cavity in shaping the microbial community in healthy lungs. In contrast, the microbiome of diseased lungs was readily distinguished as being under active selection. We also assessed the viability of microbes from lung samples by cultivation with a variety of media and incubation conditions. Bacteria recovered by cultivation from healthy lungs represented species that comprised 61% of the 16S rRNA-encoding gene sequences derived from bronchoalveolar lavage samples. IMPORTANCE Neutral distribution of microbes is a distinguishing feature of the microbiome in healthy lungs, wherein constant dispersal of bacteria from the oral cavity overrides differential growth of bacteria. No bacterial species consistently deviated from the model predictions in healthy lungs, although representatives of many of the dispersed species were readily cultivated. In contrast, bacterial populations in diseased lungs were identified as being under active selection. Quantification of the relative importance of selection and neutral processes such as dispersal in shaping the healthy lung microbiome is a first step toward understanding its impacts on host health.
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Abstract
UNLABELLED DNA from phylogenetically diverse microbes is routinely recovered from healthy human lungs and used to define the lung microbiome. The proportion of this DNA originating from microbes adapted to the lungs, as opposed to microbes dispersing to the lungs from other body sites and the atmosphere, is not known. We use a neutral model of community ecology to distinguish members of the lung microbiome whose presence is consistent with dispersal from other body sites and those that deviate from the model, suggesting a competitive advantage to these microbes in the lungs. We find that the composition of the healthy lung microbiome is consistent with predictions of the neutral model, reflecting the overriding role of dispersal of microbes from the oral cavity in shaping the microbial community in healthy lungs. In contrast, the microbiome of diseased lungs was readily distinguished as being under active selection. We also assessed the viability of microbes from lung samples by cultivation with a variety of media and incubation conditions. Bacteria recovered by cultivation from healthy lungs represented species that comprised 61% of the 16S rRNA-encoding gene sequences derived from bronchoalveolar lavage samples. IMPORTANCE Neutral distribution of microbes is a distinguishing feature of the microbiome in healthy lungs, wherein constant dispersal of bacteria from the oral cavity overrides differential growth of bacteria. No bacterial species consistently deviated from the model predictions in healthy lungs, although representatives of many of the dispersed species were readily cultivated. In contrast, bacterial populations in diseased lungs were identified as being under active selection. Quantification of the relative importance of selection and neutral processes such as dispersal in shaping the healthy lung microbiome is a first step toward understanding its impacts on host health.
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De Schryver P, Vadstein O. Ecological theory as a foundation to control pathogenic invasion in aquaculture. THE ISME JOURNAL 2014; 8:2360-8. [PMID: 24892581 PMCID: PMC4260705 DOI: 10.1038/ismej.2014.84] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 03/20/2014] [Accepted: 04/18/2014] [Indexed: 01/02/2023]
Abstract
Detrimental host-pathogen interactions are a normal phenomenon in aquaculture animal production, and have been counteracted by prophylactic use of antibiotics. Especially, the youngest life stages of cultivated aquatic animals are susceptible to pathogen invasion, resulting in disease and mortality. To establish a more sustainable aquatic food production, there is a need for new microbial management strategies that focus on 'join them' and not the traditional 'beat them' approaches. We argue that ecological theory could serve as a foundation for developing sustainable microbial management methods that prevent pathogenic disease in larviculture. Management of the water microbiota in aquaculture systems according to ecological selection principles has been shown to decrease opportunistic pathogen pressure and to result in an improved performance of the cultured animals. We hypothesize that manipulation of the biodiversity of the gut microbiota can increase the host's resistance against pathogenic invasion and infection. However, substantial barriers need to be overcome before active management of the intestinal microbiota can effectively be applied in larviculture.
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Affiliation(s)
- Peter De Schryver
- Laboratory of Aquaculture and Artemia Reference Center, Ghent University, Ghent, Belgium
| | - Olav Vadstein
- Department of Biotechnology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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Abstract
Recent research has expanded our understanding of microbial community assembly. However, the field of community ecology is inaccessible to many microbial ecologists because of inconsistent and often confusing terminology as well as unnecessarily polarizing debates. Thus, we review recent literature on microbial community assembly, using the framework of Vellend (Q. Rev. Biol. 85:183-206, 2010) in an effort to synthesize and unify these contributions. We begin by discussing patterns in microbial biogeography and then describe four basic processes (diversification, dispersal, selection, and drift) that contribute to community assembly. We also discuss different combinations of these processes and where and when they may be most important for shaping microbial communities. The spatial and temporal scales of microbial community assembly are also discussed in relation to assembly processes. Throughout this review paper, we highlight differences between microbes and macroorganisms and generate hypotheses describing how these differences may be important for community assembly. We end by discussing the implications of microbial assembly processes for ecosystem function and biodiversity.
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Trejo-Barocio P, Arita HT. The co-occurrence of species and the co-diversity of sites in neutral models of biodiversity. PLoS One 2013; 8:e79918. [PMID: 24244579 PMCID: PMC3823601 DOI: 10.1371/journal.pone.0079918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 09/27/2013] [Indexed: 11/24/2022] Open
Abstract
Patterns of co-occurrence of species are widely used to assess the fit of ecological neutral models to empirical patterns. The mathematically equivalent patterns of co-diversity of sites, in contrast, have been considered only indirectly and analyses normally are focused on the spatial distribution of species richness, rather than on the patterns of species sharing. Here we use two analytical tools (range-diversity plots and rank plots) to assess the predictions of simple neutral models in relation to patterns of co-occurrence and co-diversity. Whereas a fully stochastic null model predicts zero average among species and among sites, neutral models generate systems with low levels of covariance among species and high levels of positive covariance among sites. These patterns vary with different combinations of dispersal and speciation rates, but are always linked to the shape, symmetry, and spread of the range-size and species-richness frequency distributions. Non-homogeneous patterns of diversity and distribution arise in neutral models because of the spatial arrangement of sites and their concomitant similarity, which is reflected also in the spread of the range-size frequency distribution. The nearly null covariance among species, in contrast, implies low variance in species richness of sites and very slim frequency distributions. In real world assemblages of Mexican volant and non-volant mammals, patterns of range-size and species-richness frequency distribution are similar to those generated by neutral models. However, when the comparison includes the covariance both for species (co-occurrence) and for sites (co-diversity), empirical patterns differ significantly from the predictions of neutral models. Because of the mathematical links between the covariance in the distribution of species and the variance of species-richness values and between the covariance in species sharing among sites and the variance of range-size values, a full understanding of patterns of diversity calls for the simultaneous analysis of co-occurrence and co-diversity.
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Affiliation(s)
- Paulina Trejo-Barocio
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, México, D. F., México
| | - Héctor T. Arita
- Centro de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
- * E-mail:
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Xiao S, Zhao L, Zhang JL, Wang XT, Chen SY. The integration of facilitation into the neutral theory of community assembly. Ecol Modell 2013. [DOI: 10.1016/j.ecolmodel.2012.12.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Desjardins-Proulx P, Gravel D. A complex speciation-richness relationship in a simple neutral model. Ecol Evol 2012; 2:1781-90. [PMID: 22957181 PMCID: PMC3433983 DOI: 10.1002/ece3.292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Revised: 05/11/2012] [Accepted: 05/15/2012] [Indexed: 12/05/2022] Open
Abstract
Speciation is the “elephant in the room” of community ecology. As the ultimate source of biodiversity, its integration in ecology's theoretical corpus is necessary to understand community assembly. Yet, speciation is often completely ignored or stripped of its spatial dimension. Recent approaches based on network theory have allowed ecologists to effectively model complex landscapes. In this study, we use this framework to model allopatric and parapatric speciation in networks of communities. We focus on the relationship between speciation, richness, and the spatial structure of communities. We find a strong opposition between speciation and local richness, with speciation being more common in isolated communities and local richness being higher in more connected communities. Unlike previous models, we also find a transition to a positive relationship between speciation and local richness when dispersal is low and the number of communities is small. We use several measures of centrality to characterize the effect of network structure on diversity. The degree, the simplest measure of centrality, is the best predictor of local richness and speciation, although it loses some of its predictive power as connectivity grows. Our framework shows how a simple neutral model can be combined with network theory to reveal complex relationships between speciation, richness, and the spatial organization of populations.
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Affiliation(s)
- Philippe Desjardins-Proulx
- Canada Research Chair on Terrestrial Ecosystems, Département de biologie, chimie et géographique, Université du Québec à Rimouski300 Allée des Ursulines, Québec, G5L 3A1, Canada
- College of Engineering, University of Illinois at ChicagoChicago, Illinois
| | - Dominique Gravel
- Canada Research Chair on Terrestrial Ecosystems, Département de biologie, chimie et géographique, Université du Québec à Rimouski300 Allée des Ursulines, Québec, G5L 3A1, Canada
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Etienne RS, Rosindell J. Comment on "Global correlations in tropical tree species richness and abundance reject neutrality". Science 2012; 336:1639; author reply 1639. [PMID: 22745401 DOI: 10.1126/science.1222056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Ricklefs and Renner (Reports, 27 January 2012, p. 464) showed correlations of species richness and individual abundance within families across continents and claimed that neutral theory predicts no such correlation. However, they did not substantiate this claim quantitatively with a neutral model. Here, we show that neutral theory can be consistent with these correlations and, consequently, that the correlations alone cannot reject neutrality.
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Affiliation(s)
- Rampal S Etienne
- Community and Conservation Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen, Box 11103, 9700 CC Groningen, Netherlands
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Rosindell J, Hubbell SP, He F, Harmon LJ, Etienne RS. The case for ecological neutral theory. Trends Ecol Evol 2012; 27:203-8. [PMID: 22341498 DOI: 10.1016/j.tree.2012.01.004] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Revised: 01/15/2012] [Accepted: 01/18/2012] [Indexed: 10/28/2022]
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