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Velasco JA, Pinto-Ledezma JN. Mapping species diversification metrics in macroecology: Prospects and challenges. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.951271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The intersection of macroecology and macroevolution is one of today’s most active research in biology. In the last decade, we have witnessed a steady increment of macroecological studies that use metrics attempting to capture macroevolutionary processes to explain present-day biodiversity patterns. Evolutionary explanations of current species richness gradients are fundamental for understanding how diversity accumulates in a region. Although multiple hypotheses have been proposed to explain the patterns we observe in nature, it is well-known that the present-day diversity patterns result from speciation, extinction, colonization from nearby areas, or a combination of these macroevolutionary processes. Whether these metrics capture macroevolutionary processes across space is unknown. Some tip-rate metrics calculated directly from a phylogenetic tree (e.g., mean root distance -MRD-; mean diversification rate -mDR-) seem to return very similar geographical patterns regardless of how they are estimated (e.g., using branch lengths explicitly or not). Model-based tip-rate metrics —those estimated using macroevolutionary mixtures, e.g., the BAMM approach— seem to provide better net diversification estimates than only speciation rates. We argue that the lack of appropriate estimates of extinction and dispersal rates in phylogenetic trees may strongly limit our inferences about how species richness gradients have emerged at spatial and temporal scales. Here, we present a literature review about this topic and empirical comparisons between select taxa with several of these metrics. We implemented a simple null model approach to evaluate whether mapping of these metrics deviates from a random sampling process. We show that phylogenetic metrics by themselves are relatively poor at capturing speciation, extinction, and dispersal processes across geographical gradients. Furthermore, we provide evidence of how parametric biogeographic methods can improve our inference of past events and, therefore, our conclusions about the evolutionary processes driving biodiversity patterns. We recommend that further studies include several approaches simultaneously (e.g., spatial diversification modeling, parametric biogeographic methods, simulations) to disentangle the relative role of speciation, extinction, and dispersal in the generation and maintenance of species richness gradients at regional and global scales.
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Global variation in diversification rate and species richness are unlinked in plants. Proc Natl Acad Sci U S A 2022; 119:e2120662119. [PMID: 35767644 PMCID: PMC9271200 DOI: 10.1073/pnas.2120662119] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Species richness varies immensely around the world. Variation in the rate of diversification (speciation minus extinction) is often hypothesized to explain this pattern, while alternative explanations invoke time or ecological carrying capacities as drivers. Focusing on seed plants, the world's most important engineers of terrestrial ecosystems, we investigated the role of diversification rate as a link between the environment and global species richness patterns. Applying structural equation modeling to a comprehensive distribution dataset and phylogenetic tree covering all circa 332,000 seed plant species and 99.9% of the world's terrestrial surface (excluding Antarctica), we test five broad hypotheses postulating that diversification serves as a mechanistic link between species richness and climate, climatic stability, seasonality, environmental heterogeneity, or the distribution of biomes. Our results show that the global patterns of species richness and diversification rate are entirely independent. Diversification rates were not highest in warm and wet climates, running counter to the Metabolic Theory of Ecology, one of the dominant explanations for global gradients in species richness. Instead, diversification rates were highest in edaphically diverse, dry areas that have experienced climate change during the Neogene. Meanwhile, we confirmed climate and environmental heterogeneity as the main drivers of species richness, but these effects did not involve diversification rates as a mechanistic link, calling for alternative explanations. We conclude that high species richness is likely driven by the antiquity of wet tropical areas (supporting the "tropical conservatism hypothesis") or the high ecological carrying capacity of warm, wet, and/or environmentally heterogeneous environments.
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Ding Y, Pan B, Zhao G, Sun C, Han X, Li M. Geo-climatic factors weaken the effectiveness of phytoplankton diversity as a water quality indicator in a large sediment-laden river. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 792:148346. [PMID: 34144241 DOI: 10.1016/j.scitotenv.2021.148346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/22/2021] [Accepted: 06/05/2021] [Indexed: 06/12/2023]
Abstract
The study aims to determine whether phytoplankton diversity can be used as an indicator of water quality in large-scale sediment-laden rivers with heterogeneous environmental conditions. We hypothesized that environmental factors, such as sediment load, water surface slope, and precipitation, may impact the effectiveness of using phytoplankton diversity as a water quality indicator. To test this hypothesis, the Yellow River was selected for phytoplankton diversity and water quality assessments. We measured water quality parameters, calculated phytoplankton diversity indices, and collected data on geo-climatic variables at 130 sampling points in the Yellow River mainstream over two seasons (spring and autumn) in 2019. The results of the water quality assessment based on phytoplankton diversity indices were compared with those based on water quality index (WQI). Correlation analysis, multiple stepwise regression, distance-based redundancy analysis, and regression modeling were used to explore the biogeographical patterns and drivers of phytoplankton diversity. According to the WQI, the water quality gradually deteriorated from the source to the estuary of the river. Three biodiversity indices (Margalef, Pielou, and Shannon-Wiener) indicated that the water quality varied dynamically in the middle reaches of the river. The actual relationships between the biodiversity indices and WQI did not fit well with the standard curves of water quality classification based on the respective biodiversity indices and WQI. Variation partitioning analysis indicated that water quality parameters, such as sediment and nutrient load, were the dominant drivers of variation in phytoplankton diversity in most cases, with the contribution ranging from 11.0% to 25.7%. Geo-climatic factors, such as water surface slope and annual mean precipitation, also affected phytoplankton diversity, with the contribution reaching 27.8%. Therefore, in sediment-laden rivers with a large geographical span and complex environment, phytoplankton diversity cannot be used as a suitable water quality indicator, albeit it can reflect habitat changes to a certain extent.
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Affiliation(s)
- Yitong Ding
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Baozhu Pan
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China.
| | - Gengnan Zhao
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China.
| | - Changshun Sun
- Shaanxi Provincial Academy of Environmental Science, Xi'an 710061, China
| | - Xu Han
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Ming Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China.
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Pinkert S, Zeuss D, Dijkstra KB, Kipping J, Clausnitzer V, Brunzel S, Brandl R. Climate–diversity relationships underlying cross‐taxon diversity of the African fauna and their implications for conservation. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- Stefan Pinkert
- Faculty of Biology Ecology – Animal Ecology Philipps‐Universität Marburg Marburg Germany
- Ecology & Evolutionary Biology Yale University New Haven CT USA
| | - Dirk Zeuss
- Faculty of Geography Environmental Informatics Philipps‐Universität Marburg Marburg Germany
| | | | - Jens Kipping
- Department of Architecture Faculty Management and Geoinformation University of Applied Sciences Anhalt Köthen Germany
- BioCart Kipping, Environmental Consultant Taucha Germany
| | | | - Stefan Brunzel
- Faculty of Landscape Architecture, Biodiversity and Species Conservation University of Applied Sciences Erfurt Erfurt Germany
| | - Roland Brandl
- Faculty of Biology Ecology – Animal Ecology Philipps‐Universität Marburg Marburg Germany
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Lyu Y, Wang X, Luo J. Geographic patterns of insect diversity across China's nature reserves: The roles of niche conservatism and range overlapping. Ecol Evol 2020; 10:3305-3317. [PMID: 32273988 PMCID: PMC7141035 DOI: 10.1002/ece3.6097] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 01/21/2020] [Accepted: 01/24/2020] [Indexed: 01/18/2023] Open
Abstract
AIM Insects are the most species-rich clade in the world, but the broad-scale diversity pattern and the potential drivers have not been well documented for the clade as a whole. We aimed to examine the relative roles of contemporary and historical climate, niche conservatism, range overlapping, and other environmental factors on geographic patterns of species richness and phylogenetic structure, for insects across China. LOCATION China. METHODS We collected insect data from 184 nature reserves and examined geographic patterns of species richness and mean root distance (MRD, a metric of the evolutionary development of assemblages) for different biogeographic affinities (Palearctic, Oriental, and widespread species) and for clades originated during the warm and cold geohistorical periods ("warm clades" and "cold clades," respectively). We related richness and MRD to contemporary and historical climate, area, habitat heterogeneity, and human disturbance to evaluate their relative importance. RESULTS Total species richness revealed a hump-shaped latitudinal pattern, peaking between 30°~35°N. Richness patterns differed markedly among evolutionary groups: Oriental species richness decreased significantly with higher latitude but Palearctic species increased, while other groups again peaked between 30°~35°N. The range overlapping of different biogeographic groups in midlatitudes may be an important contributor to humped latitudinal richness patterns. MRD was positively related to latitude and increased more rapidly for "warm clades" than "cold clades." Historical climate factors (especially winter coldness) were among the strongest predictors for both richness and phylogenetic patterns, for each evolutionary group, suggesting the strong influence of niche conservatism. CONCLUSIONS The hump-shaped latitudinal pattern of insect richness in China is mainly shaped by niche conservatism and range overlapping, supplemented by habitat heterogeneity and contemporary climate. The role of niche conservatism and range overlapping may have been overlooked if only total species richness was analyzed, suggesting the importance of examining different evolutionary groups separately.
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Affiliation(s)
- Yueming Lyu
- College of ForestryBeijing Forestry UniversityBeijingChina
| | - Xiangping Wang
- College of ForestryBeijing Forestry UniversityBeijingChina
| | - Juchun Luo
- College of ForestryBeijing Forestry UniversityBeijingChina
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Velasco JA, Villalobos F, Diniz-Filho JAF, Algar AC, Flores-Villela O, KÖhler G, Poe S, Martinez-Meyer E. Climatic and evolutionary factors shaping geographical gradients of species richness in Anolis lizards. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/blx160] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Julian A Velasco
- Museo de Zoología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, Mexico
| | - Fabricio Villalobos
- Red de Biología Evolutiva, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
- Departamento de Ecologia, ICB, Universidade Federal de Goiás, Brasil
| | | | - Adam C Algar
- School of Geography, University of Nottingham, Sir Clive Granger Building, Nottingham, UK
| | - Oscar Flores-Villela
- Museo de Zoología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, Mexico
| | - Gunther KÖhler
- Senckenberg Forschungsinstitut und Naturmuseum, Frankfurt am Main, Germany
| | - Steven Poe
- Department of Biology, University of New Mexico, Albuquerque, NM, USA
| | - Enrique Martinez-Meyer
- Instituto de Biología, Universidad Nacional Autónoma de México, DF and Centro del Cambio Global y la Sustentabilidad, AC, Villahermosa, Mexico
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Ferrer-Castán D, Morales-Barbero J, Vetaas OR. Water-energy dynamics, habitat heterogeneity, history, and broad-scale patterns of mammal diversity. ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2016. [DOI: 10.1016/j.actao.2016.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
We show that Streptomyces biogeography in soils across North America is influenced by the regional diversification of microorganisms due to dispersal limitation and genetic drift. Streptomyces spp. form desiccation-resistant spores, which can be dispersed on the wind, allowing for a strong test of whether dispersal limitation governs patterns of terrestrial microbial diversity. We employed an approach that has high sensitivity for determining the effects of genetic drift. Specifically, we examined the genetic diversity and phylogeography of physiologically similar Streptomyces strains isolated from geographically distributed yet ecologically similar habitats. We found that Streptomyces beta diversity scales with geographic distance and both beta diversity and phylogenetic diversity manifest in a latitudinal diversity gradient. This pattern of Streptomyces biogeography resembles patterns seen for diverse species of plants and animals, and we therefore evaluated these data in the context of ecological and evolutionary hypotheses proposed to explain latitudinal diversity gradients. The data are consistent with the hypothesis that niche conservatism limits dispersal, and historical patterns of glaciation have limited the time for speciation in higher-latitude sites. Most notably, higher-latitude sites have lower phylogenetic diversity, higher phylogenetic clustering, and evidence of range expansion from lower latitudes. In addition, patterns of beta diversity partition with respect to the glacial history of sites. Hence, the data support the hypothesis that extant patterns of Streptomyces biogeography have been driven by historical patterns of glaciation and are the result of demographic range expansion, dispersal limitation, and regional diversification due to drift. Biogeographic patterns provide insight into the evolutionary and ecological processes that govern biodiversity. However, the evolutionary and ecological processes that govern terrestrial microbial diversity remain poorly characterized. We evaluated the biogeography of the genus Streptomyces to show that the diversity of terrestrial bacteria is governed by many of the same processes that govern the diversity of many plant and animal species. While bacteria of the genus Streptomyces are a preeminent source of antibiotics, their evolutionary history, biogeography, and biodiversity remain poorly characterized. The observations we describe provide insight into the drivers of Streptomyces biodiversity and the processes that underlie microbial diversification in terrestrial habitats.
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Algar AC, Kerr JT, Currie DJ. Evolutionary constraints on regional faunas: whom, but not how many. Ecol Lett 2015; 12:57-65. [PMID: 19049512 DOI: 10.1111/j.1461-0248.2008.01260.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The latitudinal diversity gradient has been hypothesized to reflect past evolutionary dynamics driven by climatic niche conservation during cladogenesis, i.e. the tropical conservatism hypothesis. Here we show that the species diversity of treefrogs (Hylidae) across the western hemisphere is actually independent of evolutionary niche dynamics. We evaluated three key predictions of the tropical conservatism hypothesis that relate to the relationships between climate, species richness and the phylogenetic structure of regional treefrog faunas across the continental Americas. Species composition was dependent on the inability of some lineages to evolve cold tolerance, but the actual number of species in a region was strongly predicted by precipitation, not temperature. Moreover, phylogenetic structure was independent of precipitation. Thus, species in low-richness areas were no more closely related than species in highly diverse regions. These results provide no support for the tropical conservatism hypothesis. Instead, they show that regional species composition and richness are constrained by different climatic components, demonstrating that global biodiversity gradients can be independent of niche stasis during cladogenesis.
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Affiliation(s)
- Adam C Algar
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON K1N 6N5, Canada
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Matamoros WA, Hoagstrom CW, Schaefer JF, Kreiser BR. Fish faunal provinces of the conterminous United States of America reflect historical geography and familial composition. Biol Rev Camb Philos Soc 2015; 91:813-32. [PMID: 26031190 DOI: 10.1111/brv.12196] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 04/18/2015] [Accepted: 04/28/2015] [Indexed: 11/30/2022]
Abstract
Although the conterminous USA has a long history of ichthyological exploration, the description of biogeographical provinces has been ad hoc. In this study we quantitatively determined fish faunal provinces and interpreted them in the context of the geological history of North America. We also evaluated influences of major river basin occupancy and contemporary environmental factors on provincial patterns. Our data set comprised 794 native fishes, which we used to generate a presence and absence matrix for U.S. Geological Survey (USGS) four-digit hydrologic units. Three nested data sets were analysed separately: primary freshwater families, continental freshwater families (including primary and secondary families) and all freshwater families (including primary, secondary and peripheral families). We used clustering analysis to delimit faunal breaks and one-way analysis of similarity (ANOSIM) to determine significance among clusters (i.e. provinces). We used an indicator-species analysis to identify species that contributed most to province delineations and a similarity-percentage (SIMPER) analysis to describe the relative influence of representatives from each category (i.e. primary, secondary, peripheral) on provincial boundaries. Lastly, we used a parsimony redundancy analysis to determine the roles of historical (i.e. major river basin) and contemporary environmental factors in shaping provinces. Analysis of the nested data sets revealed lessening provincial structure with inclusion of more families. There were 10 primary freshwater provinces, 9 continental freshwater provinces and 7 all freshwater provinces. Major basin occupancy, but not contemporary environmental factors, explained substantial variance in faunal similarities among provinces. However, provincial boundaries did not conform strictly to modern river basins, but reflected river-drainage connections of the Quaternary. Provinces represent broad-scale patterns of endemism and provide a starting point for future studies. Relative malleability of province boundaries in the continental interior highlights this region as biogeographically diverse and dynamic. Interior-core provinces of this region (Central Gulf Coastal Plains, Northern Interior) have not been recognized previously and warrant further study.
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Affiliation(s)
- Wilfredo A Matamoros
- Laboratorio de Helmintología, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado Postal 70-153, 04510 México, D. F., México.,Department of Biological Sciences, The University of Southern Mississippi, 118 College Dr., Box 5018, Hattiesburg, MS 39406, U.S.A.,Coleccion de ctiología, Facultad de Ciencias Biológicas, Universidad de Ciencias y Artes de Chiapas, Libramiento Norte Poniente 1150, Col. Lajas Maciel, C.P. 29039, Tuxtla Gutiérrez, Chiapas, México
| | - Christopher W Hoagstrom
- Department of Zoology, Weber State University, 1415 Edvalson Street, Dept. 2505, Ogden, UT 84408-2505, U.S.A
| | - Jacob F Schaefer
- Department of Biological Sciences, The University of Southern Mississippi, 118 College Dr., Box 5018, Hattiesburg, MS 39406, U.S.A
| | - Brian R Kreiser
- Department of Biological Sciences, The University of Southern Mississippi, 118 College Dr., Box 5018, Hattiesburg, MS 39406, U.S.A
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11
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Hurlbert AH, Stegen JC. When should species richness be energy limited, and how would we know? Ecol Lett 2014; 17:401-13. [DOI: 10.1111/ele.12240] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 09/02/2013] [Accepted: 12/06/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Allen H. Hurlbert
- Department of Biology; University of North Carolina; Chapel Hill NC 27599-3280 USA
- Curriculum for Environment and Ecology; University of North Carolina; Chapel Hill NC 27599 USA
| | - James C. Stegen
- Pacific Northwest National Laboratory; 902 Battelle Blvd P.O. Box 999, MSIN J4-18 Richland WA 99352 USA
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12
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Baselga A, Gómez-Rodríguez C, Lobo JM. Historical legacies in world amphibian diversity revealed by the turnover and nestedness components of Beta diversity. PLoS One 2012; 7:e32341. [PMID: 22384222 PMCID: PMC3285684 DOI: 10.1371/journal.pone.0032341] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 01/27/2012] [Indexed: 11/18/2022] Open
Abstract
Historic processes are expected to influence present diversity patterns in combination with contemporary environmental factors. We hypothesise that the joint use of beta diversity partitioning methods and a threshold-based approach may help reveal the effect of large-scale historic processes on present biodiversity. We partitioned intra-regional beta diversity into its turnover (differences in composition caused by species replacements) and nestedness-resultant (differences in species composition caused by species losses) components. We used piecewise regressions to show that, for amphibian beta diversity, two different world regions can be distinguished. Below parallel 37, beta diversity is dominated by turnover, while above parallel 37, beta diversity is dominated by nestedness. Notably, these regions are revealed when the piecewise regression method is applied to the relationship between latitude and the difference between the Last Glacial Maximum (LGM) and the present temperature but not when present energy-water factors are analysed. When this threshold effect of historic climatic change is partialled out, current energy-water variables become more relevant to the nestedness-resultant dissimilarity patterns, while mountainous areas are associated with higher spatial turnover. This result suggests that nested patterns are caused by species losses that are determined by physiological constraints, whereas turnover is associated with speciation and/or Pleistocene refugia. Thus, the new threshold-based view may help reveal the role of historic factors in shaping present amphibian beta diversity patterns.
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Affiliation(s)
- Andrés Baselga
- Departamento de Zoología, Facultad de Biología, Universidad de Santiago de Compostela, Santiago de Compostela, Spain.
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Stevens RD. Relative effects of time for speciation and tropical niche conservatism on the latitudinal diversity gradient of phyllostomid bats. Proc Biol Sci 2011; 278:2528-36. [PMID: 21208951 DOI: 10.1098/rspb.2010.2341] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Determinants of contemporary patterns of diversity, particularly those spanning extensive latitudinal gradients, are some of the most intensely debated issues in ecology. Recently, focus has shifted from a contemporary environmental perspective to a historical one in an attempt to better understand the construction of latitudinal gradients. Although the vast majority of research on historical mechanisms has focused on tropical niche conservatism (TNC), other historical scenarios could produce similar latitudinal gradients. Herein, I formalize predictions to distinguish between two such historical processes--namely time for speciation (TFS) and TNC--and test relative support based on diversity gradients of New World bats. TFS and TNC are distinctly spatial and environmental mechanisms, respectively. Nonetheless, because of the way that environmental characteristics vary spatially, these two mechanisms are hard to distinguish. Evidence provided herein suggests that TNC has had a more important effect than TFS in determining diversity gradients of New World bats. Indeed, relative effects of different historical mechanisms, as well as relative effects of historical and contemporary environmental determinants, are probably context-dependent. Future research should move away from attempting to identify the mechanism with primacy and instead attempt to understand the particular contexts in which different mechanisms have greater influence on diversity gradients.
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Affiliation(s)
- Richard D Stevens
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
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Pavoine S, Bonsall MB. Measuring biodiversity to explain community assembly: a unified approach. Biol Rev Camb Philos Soc 2010; 86:792-812. [DOI: 10.1111/j.1469-185x.2010.00171.x] [Citation(s) in RCA: 402] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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GRIFFITHS DAVID. Pattern and process in the distribution of North American freshwater fish. Biol J Linn Soc Lond 2010. [DOI: 10.1111/j.1095-8312.2010.01404.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Krug AZ, Jablonski D, Valentine JW. Contrarian clade confirms the ubiquity of spatial origination patterns in the production of latitudinal diversity gradients. Proc Natl Acad Sci U S A 2007; 104:18129-34. [PMID: 17989214 PMCID: PMC2084308 DOI: 10.1073/pnas.0709202104] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Indexed: 11/18/2022] Open
Abstract
The latitudinal diversity gradient (LDG), wherein the number of species and higher taxa peaks in the tropics and decreases toward the poles, is the best-documented large-scale diversity pattern on Earth, but hypotheses explaining the standard LDG must also account for rare "contrarian" taxa that show diversity maxima outside of the tropics. For marine bivalves, one of the few groups that provide spatially explicit temporal data on a global scale, we show that a major contrarian group, the Anomalodesmata, unexpectedly exhibits the same large-scale dynamics as related clades having normal LDGs in two key respects. First, maxima in standing genus diversity and genus origination rates coincide spatially. Second, the strength of a clade's present-day LDG is significantly related to the proportion of its living genera that originated in the tropics during the late Cenozoic, with the contrarian gradient strength at both species and genus level predicted quantitatively by the values for the other clades. Geologic age distributions indicate that the anomalous LDG results from origination that is damped in the tropics rather than heightened in the temperate zones. The pervasive role of spatial origination patterns in shaping LDGs, regardless of the position of their diversity maxima, corroborates hypotheses based on clades showing standard gradients and underscores the insights that contrarian groups can provide into general principles of diversity dynamics.
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Affiliation(s)
- Andrew Z. Krug
- *Department of Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637; and
| | - David Jablonski
- *Department of Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637; and
| | - James W. Valentine
- Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, CA 94720-3140
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Hawkins BA, Diniz-Filho JAF, Jaramillo CA, Soeller SA. Climate, Niche Conservatism, and the Global Bird Diversity Gradient. Am Nat 2007; 170 Suppl 2:S16-27. [PMID: 17874382 DOI: 10.1086/519009] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
We tested the proposition that there are more species in the tropics because basal clades adapted to warm paleoclimates have been lost in regions now experiencing cool climates. Molecular phylogenies were used to classify species as "basal" and "derived" based on their family, and their richness patterns were contrasted. Path models also evaluated environmental predictors of richness patterns. As predicted, basal clades are more diverse in the lowland tropics, whereas derived clades are more diverse in the extratropics and high-altitude tropics. Seventy-four percent of the variation in bird richness was explained by environmental variables, but models differed for basal and derived groups. The overall gradient is described by the spatial pattern of basal clades, although there are differences in the Old and New Worlds. We conclude that in ecological time, the global richness gradient reflects birds' responses to climatic gradients, partially operating via plants. Over evolutionary time, the gradient primarily reflects the extirpation of species in older clades from parts of the world that have become cooler in the present. A strong secondary effect arises from dispersal of clades from centers of origin and subsequent radiations. Overall, the diversity gradient is well explained by niche conservatism and the "time-for-speciation" hypothesis.
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Affiliation(s)
- Bradford A Hawkins
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California 92697 USA.
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Roy K, Goldberg EE. Origination, Extinction, and Dispersal: Integrative Models for Understanding Present‐Day Diversity Gradients. Am Nat 2007; 170 Suppl 2:S71-85. [PMID: 17874386 DOI: 10.1086/519403] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Species diversity gradients seen today are, to a large degree, a product of history. Spatially nonrandom originations, extinctions, and changes in geographic distributions can create gradients in species and higher-taxon richness, but the relative roles of each of these processes remain poorly documented. Existing explanations of diversity gradients have tended to focus on either macroevolutionary or biogeographic processes; integrative models that include both are largely lacking. We used simple models that incorporate origination and extinction rates along with dispersal of taxa between regions to show that dispersal not only affects regional richness patterns but also has a strong influence on the average age of taxa present in a region. Failure to take into account the effects of dispersal can, in principle, lead to biased estimates of diversification rates and potentially wrong conclusions regarding processes driving latitudinal and other gradients in diversity. Thus, it is critical to include the effects of dispersal when formulating and testing hypotheses about the causes of large-scale gradients in diversity. Finally, the model results, in conjunction with the results of existing empirical studies, suggest that the nature of macroevolutionary and biogeographic processes may differ between terrestrial and marine diversity gradients.
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Affiliation(s)
- Kaustuv Roy
- Section of Ecology, Behavior and Evolution, University of California San Diego, La Jolla, California 92093, USA.
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Stevens RD. Historical processes enhance patterns of diversity along latitudinal gradients. Proc Biol Sci 2006; 273:2283-9. [PMID: 16928629 PMCID: PMC1636076 DOI: 10.1098/rspb.2006.3596] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
One of the more vexing issues in ecology is how historical processes affect contemporary patterns of biodiversity. Accordingly, few models have been presented. Two corollary models (centre of origin, time-for-speciation) can be used to make quantitative predictions characterizing the tropical niche conservatism hypothesis and describe diversification as diffusion and subsequent cladogenesis of species away from the place of origin of a higher taxon in the tropics. Predictions derived from such models are: (i) species richness declines toward the periphery of the range of a higher taxon; (ii) taxa are more derived toward the periphery than the centre; (iii) ages of taxa are lower toward the periphery than the centre; and (iv) ages and measures of derivedness are less variable toward the periphery of the range of a higher taxon. I tested these predictions to better understand the formation of one of the most ubiquitous patterns of biodiversity-the latitudinal gradient in species richness. Results indicate well-supported predictions for New World leaf-nosed bats and that diversification has had strong influences on latitudinal gradients of species richness. A better understanding of how evolutionary diversification of taxa contributes to formation of patterns of species richness along environmental gradients is necessary to fully understand spatial variation in biodiversity.
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Affiliation(s)
- Richard D Stevens
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
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Evans KL, Warren PH, Gaston KJ. Species-energy relationships at the macroecological scale: a review of the mechanisms. Biol Rev Camb Philos Soc 2005; 80:1-25. [PMID: 15727036 DOI: 10.1017/s1464793104006517] [Citation(s) in RCA: 236] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Correlations between the amount of energy received by an assemblage and the number of species that it contains are very general, and at the macro-scale such species-energy relationships typically follow a monotonically increasing curve. Whilst the ecological literature contains frequent reports of such relationships, debate on their causal mechanisms is limited and typically focuses on the role of energy availability in controlling the number of individuals in an assemblage. Assemblages from high-energy areas may contain more individuals enabling species to maintain larger, more viable populations, whose lower extinction risk elevates species richness. Other mechanisms have, however, also been suggested. Here we identify and clarify nine principal mechanisms that may generate positive species-energy relationships at the macro-scale. We critically assess their assumptions and applicability over a range of spatial scales, derive predictions for each and assess the evidence that supports or refutes them. Our synthesis demonstrates that all mechanisms share at least one of their predictions with an alternative mechanism. Some previous studies of species-energy relationships appear not to have recognised the extent of shared predictions, and this may detract from their contribution to the debate on causal mechanisms. The combination of predictions and assumptions made by each mechanism is, however, unique, suggesting that, in principle, conclusive tests are possible. Sufficient testing of all mechanisms has yet to be conducted, and no single mechanism currently has unequivocal support. Each may contribute to species-energy relationships in some circumstances, but some mechanisms are unlikely to act simultaneously. Moreover, a limited number appear particularly likely to contribute frequently to species-energy relationships at the macro-scale. The increased population size, niche position and diversification rate mechanisms are particularly noteworthy in this context.
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Affiliation(s)
- Karl L Evans
- Biodiversity & Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
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Currie DJ, Mittelbach GG, Cornell HV, Field R, Guegan JF, Hawkins BA, Kaufman DM, Kerr JT, Oberdorff T, O'Brien E, Turner JRG. Predictions and tests of climate-based hypotheses of broad-scale variation in taxonomic richness. Ecol Lett 2004. [DOI: 10.1111/j.1461-0248.2004.00671.x] [Citation(s) in RCA: 859] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Diniz-Filho JAF, Rangel TFLVB, Hawkins BA. A test of multiple hypotheses for the species richness gradient of South American owls. Oecologia 2004; 140:633-8. [PMID: 15248060 DOI: 10.1007/s00442-004-1577-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2003] [Accepted: 03/31/2004] [Indexed: 11/30/2022]
Abstract
Many mechanisms have been proposed to explain broad scale spatial patterns in species richness. In this paper, we evaluate five explanations for geographic gradients in species richness, using South American owls as a model. We compared the explanatory power of contemporary climate, landcover diversity, spatial climatic heterogeneity, evolutionary history, and area. An important aspect of our analyses is that very different hypotheses, such as history and area, can be quantified at the same observation scale and, consequently can be incorporated into a single analytical framework. Both area effects and owl phylogenetic history were poorly associated with richness, whereas contemporary climate, climatic heterogeneity at the mesoscale and landcover diversity explained ca. 53% of the variation in species richness. We conclude that both climate and environmental heterogeneity should be retained as plausible explanations for the diversity gradient. Turnover rates and scaling effects, on the other hand, although perhaps useful for detecting faunal changes and beta diversity at local and regional scales, are not strong explanations for the owl diversity gradient.
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Qian H, Ricklefs RE. Taxon richness and climate in angiosperms: is there a globally consistent relationship that precludes region effects? Am Nat 2004; 163:773-9; discussion 780-5. [PMID: 15122494 DOI: 10.1086/383097] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2003] [Accepted: 08/20/2003] [Indexed: 11/03/2022]
Abstract
We comment on a recent paper by Francis and Currie that reports a globally consistent relationship between plant family diversity in large geographic grid cells and factors in the physical environment. This relationship was interpreted as demonstrating local ecological determination of diversity, leaving little room for regional and historical effects. We suggest that using family richness to describe patterns of diversity reduces regional effects owing to the lower endemism of plants at the family compared with the species level. Regardless of the taxonomic level of analysis, we further point out that unless regional effects are tested explicitly, statistically significant differences in diversity between regions can be overlooked. Finally, even correlations between diversity and physical conditions of the environment can have primarily historical and evolutionary origins when lineages diversify within ecological zones of origin and spread more slowly to diverse environments. Thus, local ecological determinism should not have primacy over evolutionary-historical explanations for patterns of diversity between or within regions. Ecologists must evaluate patterns in local diversity within historical and geographic, as well as ecological, contexts.
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Affiliation(s)
- Hong Qian
- Department of Botany, Research and Collections Center, Illinois State Museum, Springfield, Illinois 62703, USA.
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Currie D, Francis A. Regional versus Climatic Effect on Taxon Richness in Angiosperms: Reply to Qian and Ricklefs. Am Nat 2004. [DOI: 10.1086/383596] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Valle de Britto Rangel TFL, Felizola Diniz-Filho JA. Spatial patterns in species richness and the geometric constraint simulation model: a global analysis of mid-domain effect in Falconiformes. ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2003. [DOI: 10.1016/s1146-609x(03)00093-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Lekve K, Stenseth NC, Johansen R, Lingjaerde OC, Gjøsaeter J. Richness dependence and climatic forcing as regulating processes of coastal fish-species richness. Ecol Lett 2003. [DOI: 10.1046/j.1461-0248.2003.00453.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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van Rensburg BJ, Chown SL, Gaston KJ. Species Richness, Environmental Correlates, and Spatial Scale: A Test Using South African Birds. Am Nat 2002; 159:566-77. [DOI: 10.1086/339464] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
To a first approximation, the distribution of biodiversity across the Earth can be described in terms of a relatively small number of broad-scale spatial patterns. Although these patterns are increasingly well documented, understanding why they exist constitutes one of the most significant intellectual challenges to ecologists and biogeographers. Theory is, however, developing rapidly, improving in its internal consistency, and more readily subjected to empirical challenge.
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Affiliation(s)
- K J Gaston
- Department of Animal and Plant Sciences, University of Sheffield, UK.
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