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Liu Z, Wu D, Zhai W, Ma L. SONAR enables cell type deconvolution with spatially weighted Poisson-Gamma model for spatial transcriptomics. Nat Commun 2023; 14:4727. [PMID: 37550279 PMCID: PMC10406862 DOI: 10.1038/s41467-023-40458-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 07/25/2023] [Indexed: 08/09/2023] Open
Abstract
Recent advancements in spatial transcriptomic technologies have enabled the measurement of whole transcriptome profiles with preserved spatial context. However, limited by spatial resolution, the measured expressions at each spot are often from a mixture of multiple cells. Computational deconvolution methods designed for spatial transcriptomic data rarely make use of the valuable spatial information as well as the neighboring similarity information. Here, we propose SONAR, a Spatially weighted pOissoN-gAmma Regression model for cell-type deconvolution with spatial transcriptomic data. SONAR directly models the raw counts of spatial transcriptomic data and applies a geographically weighted regression framework that incorporates neighboring information to enhance local estimation of regional cell type composition. In addition, SONAR applies an additional elastic weighting step to adaptively filter dissimilar neighbors, which effectively prevents the introduction of local estimation bias in transition regions with sharp boundaries. We demonstrate the performance of SONAR over other state-of-the-art methods on synthetic data with various spatial patterns. We find that SONAR can accurately map region-specific cell types in real spatial transcriptomic data including mouse brain, human heart and human pancreatic ductal adenocarcinoma. We further show that SONAR can reveal the detailed distributions and fine-grained co-localization of immune cells within the microenvironment at the tumor-normal tissue margin in human liver cancer.
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Affiliation(s)
- Zhiyuan Liu
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- University of the Chinese Academy of Sciences, 100049, Beijing, China
| | - Dafei Wu
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
| | - Weiwei Zhai
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.
- University of the Chinese Academy of Sciences, 100049, Beijing, China.
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, 650223, Kunming, China.
| | - Liang Ma
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.
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Zheng B, Lin X, Yin D, Qi X. Does Tobler's first law of geography apply to internet attention? A case study of the Asian elephant northern migration event. PLoS One 2023; 18:e0282474. [PMID: 36857382 PMCID: PMC9977022 DOI: 10.1371/journal.pone.0282474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 02/16/2023] [Indexed: 03/02/2023] Open
Abstract
One of the basic assumptions of spatial theory is formulated in Waldo Tobler's first law of geography: "everything is related to everything else, but near things are more related than distant things." However, as internet space is a complex virtual space independent of the real world, whether this law is applicable to things in the internet space remains to be explored in depth. Therefore, this study takes the event of Asian elephant northern migration as an example, attempts to investigate the issue of the applicability of Tobler's first law of geography to internet attention by integrating geographic methods such as spatial visualization, spatial correlation analysis, and Geo-detector. The results show that Tobler's first law of geography does not fully apply to internet attention, which does not decay with increasing distance. Geographical distance, within certain boundaries, is influenced by "identity" and "relevance", and still plays a large role in internet attention. However, once the boundaries are exceeded, the impact of geographic distance on internet attention is weakened by the intervention of influencing factors such as the degree of information technology, population, and the strength of news media publicity. Overall, the strength of news media publicity has the greatest impact on internet attention. And when it interacts with geographic proximity, it has the most significant effect on internet attention.
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Affiliation(s)
- Boming Zheng
- School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Xijie Lin
- School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Duo Yin
- School of Geography and Remote Sensing, Guangzhou University, Guangzhou, China
| | - Xinhua Qi
- School of Geographical Sciences, Fujian Normal University, Fuzhou, China
- Institute of Geography, Fujian Normal University, Fuzhou, China
- Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry, Fujian Normal University, Fuzhou, China
- * E-mail:
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Velazco SJE, Svenning J, Ribeiro BR, Laureto LMO. On opportunities and threats to conserve the phylogenetic diversity of Neotropical palms. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13215] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Affiliation(s)
- Santiago José Elías Velazco
- Instituto de Biología Subtropical Universidad Nacional de Misiones‐CONICET Puerto Iguazú Misiones N3370BFAArgentina
| | - Jean‐Christian Svenning
- Section of Ecoinformatics and Biodiversity, Department of Bioscience Aarhus University AarhusDK‐8000Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE) Department of Bioscience, Aarhus University AarhusDK‐8000Denmark
| | - Bruno R. Ribeiro
- Programa de Pós‐Graduaçao Ecología e Evolução Instituto de Ciências Biológicas V, Universidade Federal de Goiás Goiânia Goiás 74.690‐900Brazil
| | - Livia Maira Orlandi Laureto
- Theoretical, Metacommunity and Landscape Ecology Laboratory Instituto de Ciências Biológicas V, Universidade Federal de Goiás Goiânia Goiás 74.690‐900Brazil
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Robinson JL, Fordyce JA. Species-free species distribution models describe macroecological properties of protected area networks. PLoS One 2017; 12:e0173443. [PMID: 28301488 PMCID: PMC5354291 DOI: 10.1371/journal.pone.0173443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 02/21/2017] [Indexed: 11/20/2022] Open
Abstract
Among the greatest challenges facing the conservation of plants and animal species in protected areas are threats from a rapidly changing climate. An altered climate creates both challenges and opportunities for improving the management of protected areas in networks. Increasingly, quantitative tools like species distribution modeling are used to assess the performance of protected areas and predict potential responses to changing climates for groups of species, within a predictive framework. At larger geographic domains and scales, protected area network units have spatial geoclimatic properties that can be described in the gap analysis typically used to measure or aggregate the geographic distributions of species (stacked species distribution models, or S-SDM). We extend the use of species distribution modeling techniques in order to model the climate envelope (or “footprint”) of individual protected areas within a network of protected areas distributed across the 48 conterminous United States and managed by the US National Park System. In our approach we treat each protected area as the geographic range of a hypothetical endemic species, then use MaxEnt and 5 uncorrelated BioClim variables to model the geographic distribution of the climatic envelope associated with each protected area unit (modeling the geographic area of park units as the range of a species). We describe the individual and aggregated climate envelopes predicted by a large network of 163 protected areas and briefly illustrate how macroecological measures of geodiversity can be derived from our analysis of the landscape ecological context of protected areas. To estimate trajectories of change in the temporal distribution of climatic features within a protected area network, we projected the climate envelopes of protected areas in current conditions onto a dataset of predicted future climatic conditions. Our results suggest that the climate envelopes of some parks may be locally unique or have narrow geographic distributions, and are thus prone to future shifts away from the climatic conditions in these parks in current climates. In other cases, some parks are broadly similar to large geographic regions surrounding the park or have climatic envelopes that may persist into near-term climate change. Larger parks predict larger climatic envelopes, in current conditions, but on average the predicted area of climate envelopes are smaller in our single future conditions scenario. Individual units in a protected area network may vary in the potential for climate adaptation, and adaptive management strategies for the network should account for the landscape contexts of the geodiversity or climate diversity within individual units. Conservation strategies, including maintaining connectivity, assessing the feasibility of assisted migration and other landscape restoration or enhancements can be optimized using analysis methods to assess the spatial properties of protected area networks in biogeographic and macroecological contexts.
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Affiliation(s)
- Jason L. Robinson
- Illinois Natural History Survey, Prairie Research Institute, University of Illinois, Urbana- Champaign. Champaign IL, United States of America
- * E-mail:
| | - James A. Fordyce
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, United States of America
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5
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Local Knowledge and Professional Background Have a Minimal Impact on Volunteer Citizen Science Performance in a Land-Cover Classification Task. REMOTE SENSING 2016. [DOI: 10.3390/rs8090774] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Arellano G, Tello JS, Jørgensen PM, Fuentes AF, Loza MI, Torrez V, Macía MJ. Disentangling environmental and spatial processes of community assembly in tropical forests from local to regional scales. OIKOS 2015. [DOI: 10.1111/oik.02426] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Gabriel Arellano
- Depto de Biología; Univ. Autónoma de Madrid; Calle Darwin 2 ES-28049 Madrid Spain
| | - J. Sebastián Tello
- Center for Conservation and Sustainable Development, Missouri Botanical Garden; PO Box 299 St. Louis MO 63166-0299 USA
- Escuela de Biología, Pontificia Univ. Católica del Ecuador; Av. 12 de Octubre 1076 y Roca Apdo. 17-01-2184 Quito Ecuador
| | | | - Alfredo F. Fuentes
- Herbario Nacional de Bolivia, Campus Universitario Cota-Cota; calle 27, Correo Central Cajón Postal 10077, La Paz Bolivia
| | - M. Isabel Loza
- Herbario Nacional de Bolivia, Campus Universitario Cota-Cota; calle 27, Correo Central Cajón Postal 10077, La Paz Bolivia
- Dept of Biology; Univ. of Missouri; St. Louis MO 63121 USA
| | - Vania Torrez
- Dept of Biology; Univ. of Leuven; BE-3001 Leuven Belgium
| | - Manuel J. Macía
- Depto de Biología; Univ. Autónoma de Madrid; Calle Darwin 2 ES-28049 Madrid Spain
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Eiserhardt WL, Svenning JC, Baker WJ, Couvreur TLP, Balslev H. Dispersal and niche evolution jointly shape the geographic turnover of phylogenetic clades across continents. Sci Rep 2013; 3:1164. [PMID: 23383367 PMCID: PMC3563030 DOI: 10.1038/srep01164] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 12/05/2012] [Indexed: 11/30/2022] Open
Abstract
The turnover of phylogenetic clades across space is a fundamental biodiversity pattern that may depend on long-term evolutionary processes, and that has downstream effects on other aspects of diversity including species richness and community structure. Limited niche evolution and limited dispersal are two major processes causing spatial restriction, and thus turnover, of clades. We studied the determinants of clade turnover within the World's richest floristic kingdom, the Neotropics, using the palm family (Arecaceae) as a model. We show that continental-scale clade turnover is driven by a combination of limited niche evolution - with respect to temperature and soil tolerances - and limited dispersal. These findings are consistent with strong dispersal barriers within the Neotropics, and the observation that some palm lineages are most diverse in certain biomes or climates. The importance of such deep-time effects suggest that palms might be slow to adapt or disperse in response to anthropogenic climate change.
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Affiliation(s)
- Wolf L. Eiserhardt
- Ecoinformatics and Biodiversity Group, Department of Bioscience, Aarhus University, Ny Munkegade 116, Build 1540, 8000 Aarhus C, DK
| | - Jens-Christian Svenning
- Ecoinformatics and Biodiversity Group, Department of Bioscience, Aarhus University, Ny Munkegade 116, Build 1540, 8000 Aarhus C, DK
| | | | - Thomas L. P. Couvreur
- Institut de Recherche pour le Développement (IRD), UMR DIA-DE, DYNADIV research group, 911, avenue Agropolis, BP 64501, F-34394 Montpellier cedex 5, France
- Université de Yaoundé I, Ecole Normale Supérieure, Département des Sciences Biologiques, Laboratoire de Botanique systématique et d'Ecologie, B.P. 047, Yaoundé, Cameroon
| | - Henrik Balslev
- Ecoinformatics and Biodiversity Group, Department of Bioscience, Aarhus University, Ny Munkegade 116, Build 1540, 8000 Aarhus C, DK
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Wetzel CE, Bicudo DDC, Ector L, Lobo EA, Soininen J, Landeiro VL, Bini LM. Distance decay of similarity in neotropical diatom communities. PLoS One 2012; 7:e45071. [PMID: 23028767 PMCID: PMC3441607 DOI: 10.1371/journal.pone.0045071] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 08/13/2012] [Indexed: 11/24/2022] Open
Abstract
Background The regression of similarity against distance unites several ecological phenomena, and thus provides a highly useful approach for illustrating the spatial turnover across sites. Our aim was to test whether the rates of decay in community similarity differ between diatom growth forms suggested to show different dispersal ability. We hypothesized that the diatom group with lower dispersal ability (i.e. periphyton) would show higher distance decay rates than a group with higher dispersal ability (i.e. plankton). Methods/Principal findings Periphyton and phytoplankton samples were gathered at sites distributed over an area of approximately 800 km length in the Negro River, Amazon basin, Brazil, South America (3°08′00″S; 59°54′30″W). Distance decay relationships were then estimated using distance-based regressions, and the coefficients of these regressions were compared among the groups with different dispersal abilities to assess our predictions. We found evidence that different tributaries and reaches of the Negro River harbor different diatom communities. As expected, the rates of distance decay in community similarity were higher for periphyton than for phytoplankton indicating the lower dispersal ability of periphytic taxa. Conclusions/Significance Our study demonstrates that the comparison of distance decay relationships among taxa with similar ecological requirements, but with different growth form and thus dispersal ability provides a sound approach to evaluate the effects of dispersal ability on beta diversity patterns. Our results are also in line with the growing body of evidence indicating that microorganisms exhibit biogeographic patterns. Finally, we underscore that clumbing all microbial taxa into one group may be a flawed approach to test whether microbes exhibit biogeographic patterns.
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Affiliation(s)
- Carlos E Wetzel
- Núcleo de Ecologia, Instituto de Botânica, São Paulo, SP, Brazil.
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9
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Bacaro G, Rocchini D, Duprè C, Diekmann M, Carnesecchi F, Gori V, Chiarucci A. Absence of distance decay in the similarity of plots at small extent in an urban brownfield. COMMUNITY ECOL 2012. [DOI: 10.1556/comec.13.2012.1.5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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10
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Shackell NL, Fisher JAD, Frank KT, Lawton P. Spatial scale of similarity as an indicator of metacommunity stability in exploited marine systems. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:336-348. [PMID: 22471094 DOI: 10.1890/10-2093.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The spatial scale of similarity among fish communities is characteristically large in temperate marine systems: connectivity is enhanced by high rates of dispersal during the larval/juvenile stages and the increased mobility of large-bodied fish. A larger spatial scale of similarity (low beta diversity) is advantageous in heavily exploited systems because locally depleted populations are more likely to be "rescued" by neighboring areas. We explored whether the spatial scale of similarity changed from 1970 to 2006 due to overfishing of dominant, large-bodied groundfish across a 300 000-km2 region of the Northwest Atlantic. Annually, similarities among communities decayed slowly with increasing geographic distance in this open system, but through time the decorrelation distance declined by 33%, concomitant with widespread reductions in biomass, body size, and community evenness. The decline in connectivity stemmed from an erosion of community similarity among local subregions separated by distances as small as 100 km. Larger fish, of the same species, contribute proportionally more viable offspring, so observed body size reductions will have affected maternal output. The cumulative effect of nonlinear maternal influences on egg/larval quality may have compromised the spatial scale of effective larval dispersal, which may account for the delayed recovery of certain member species. Our study adds strong support for using the spatial scale of similarity as an indicator of metacommunity stability both to understand the spatial impacts of exploitation and to refine how spatial structure is used in management plans.
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Affiliation(s)
- Nancy L Shackell
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, P.O. Box 1006, Dartmouth, Nova Scotia B2Y 4A2, Canada.
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11
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Eiserhardt WL, Svenning JC, Kissling WD, Balslev H. Geographical ecology of the palms (Arecaceae): determinants of diversity and distributions across spatial scales. ANNALS OF BOTANY 2011; 108:1391-416. [PMID: 21712297 PMCID: PMC3219491 DOI: 10.1093/aob/mcr146] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Accepted: 03/28/2011] [Indexed: 05/28/2023]
Abstract
BACKGROUND The palm family occurs in all tropical and sub-tropical regions of the world. Palms are of high ecological and economical importance, and display complex spatial patterns of species distributions and diversity. SCOPE This review summarizes empirical evidence for factors that determine palm species distributions, community composition and species richness such as the abiotic environment (climate, soil chemistry, hydrology and topography), the biotic environment (vegetation structure and species interactions) and dispersal. The importance of contemporary vs. historical impacts of these factors and the scale at which they function is discussed. Finally a hierarchical scale framework is developed to guide predictor selection for future studies. CONCLUSIONS Determinants of palm distributions, composition and richness vary with spatial scale. For species distributions, climate appears to be important at landscape and broader scales, soil, topography and vegetation at landscape and local scales, hydrology at local scales, and dispersal at all scales. For community composition, soil appears important at regional and finer scales, hydrology, topography and vegetation at landscape and local scales, and dispersal again at all scales. For species richness, climate and dispersal appear to be important at continental to global scales, soil at landscape and broader scales, and topography at landscape and finer scales. Some scale-predictor combinations have not been studied or deserve further attention, e.g. climate on regional to finer scales, and hydrology and topography on landscape and broader scales. The importance of biotic interactions - apart from general vegetation structure effects - for the geographic ecology of palms is generally underexplored. Future studies should target scale-predictor combinations and geographic domains not studied yet. To avoid biased inference, one should ideally include at least all predictors previously found important at the spatial scale of investigation.
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Affiliation(s)
| | | | | | - Henrik Balslev
- Ecoinformatics and Biodiversity Group, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
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12
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Svenning JC, Fløjgaard C, Baselga A. Climate, history and neutrality as drivers of mammal beta diversity in Europe: insights from multiscale deconstruction. J Anim Ecol 2010; 80:393-402. [PMID: 21070238 DOI: 10.1111/j.1365-2656.2010.01771.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Environmental sorting, historical factors and neutral dynamics may all drive beta diversity (change in species composition across space), but their relative importance remains unresolved. In the case of European mammals, key potential drivers of large-scale beta diversity include current climate, neutral dynamics and two historical factors: Pleistocene glaciations and peninsular dynamics (immigration from extra-regional eastern faunal source areas and inter-linked relictual survival and evolutionary differentiation in isolated areas). 2. We assessed the relative importance of these drivers using a novel analytical framework to deconstruct beta diversity of non-volant mammals in Europe (138 species) into its turnover (change in species composition because of species replacements) and nestedness components (change in species composition because of species richness differences) at continental and regional (250,000 km(2) ) scales. 3. We found continental-scale mammal beta diversity to be mainly caused by spatial turnover (99·9%), with only a small contribution (0·1%) from nestedness. 4. Current climate emerged as an important driver of beta diversity, given the strong continental-scale turnover, particularly in north-south direction, i.e., in line with the latitudinal climate gradient, and, more directly, the strong correlation of climate with spatial turnover at both continental and regional scales. 5. However, there was also evidence for the importance of non-climatic drivers. Notably, the compositional variation purely accounted for by space was greater than that purely accounted for by environment for both the turnover and the nestedness component of beta diversity. Furthermore, the strong longitudinal turnover within Southern Europe is in accordance with the region's long-term climatic stability having allowed multiple refugia and local evolutionary diversification. As expected from peninsular dynamics, there was increasing dissimilarity with geographic distance in an east-west direction because of nestedness, but only in Central and Northern Europe. 6. In conclusion, European mammal beta diversity mainly reflects spatial turnover and only to a limited extent nestedness and is driven by current climate in combination with historical - and perhaps, neutral - dynamics. These findings suggest that a key challenge for climate-change predictive studies will be taking the influence of non-climatic factors into account.
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Affiliation(s)
- Jens-Christian Svenning
- Ecoinformatics & Biodiversity Group, Department of Biological Sciences, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark.
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Timi JT, Lanfranchi AL, Luque JL. Similarity in parasite communities of the teleost fish Pinguipes brasilianus in the southwestern Atlantic: infracommunities as a tool to detect geographical patterns. Int J Parasitol 2009; 40:243-54. [PMID: 19682450 DOI: 10.1016/j.ijpara.2009.07.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 07/29/2009] [Accepted: 07/31/2009] [Indexed: 11/16/2022]
Abstract
Patterns of distance decay in similarity among communities of the fish Pinguipes brasilianus (Teleostei: Pinguipedidae) from five areas in the southwestern Atlantic were investigated to determine whether the rate of decay varied depending on the community level or the parasite guild analyzed (ectoparasites, adult endoparasites and larval endoparasites). Similarities in species composition were computed at both the component community and infracommunity levels. Similarity indices were calculated between all possible pairs of assemblages from different zones. Infracommunity similarity values between and within host populations were averaged. Significance of linear regressions for similarity values against distance was assessed using randomization tests. Different patterns were observed for each guild, and similarity among infracommunities within host populations varied accordingly. Decay in similarity over distance was recorded for most communities. The slopes differed significantly between infracommunities and component communities in all cases, and stronger decay was always observed for infracommunities. Different geographical patterns in parasite communities were a consequence of variability in parasite availability in the different regions, modulated by oceanographic conditions, as well as variation among species in terms of host specificity and life-cycles strategies. Infracommunities showed a stronger effect of distance than component communities, probably due to the influence of short term and local variability of oceanographic conditions.
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Affiliation(s)
- Juan T Timi
- Laboratorio de Parasitología, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Funes 3350, (7600) Mar del Plata, Argentina.
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