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Evaluating the correlation between area, environmental heterogeneity, and species richness using terrestrial isopods (Oniscidea) from the Pontine Islands (West Mediterranean). ORG DIVERS EVOL 2021. [DOI: 10.1007/s13127-021-00523-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AbstractArea and environmental heterogeneity influence species richness in islands. Whether area or environmental heterogeneity is more relevant in determining species richness is a central issue in island biogeography. Several models have been proposed, addressing the issue, and they can be reconducted to three main hypotheses developed to explain the species-area relationship: (1) the area-per se hypothesis (known also as the extinction-colonisation equilibrium), (2) the random placement (passive sampling), and the (3) environmental heterogeneity (habitat diversity). In this paper, considering also the possible influence of geographic distance on island species richness, we explore the correlation between area, environmental heterogeneity, and species richness by using faunistic data of Oniscidea inhabiting the Pontine Islands, a group of five small volcanic islands and several islets in the Tyrrhenian Sea, located about 60 km from the Italian mainland. We found that the colonisation of large Pontine Islands may occur via processes independent of geographic distance which could instead be an important factor at a much smaller scale. Such processes may be driven by a combination of anthropogenic influences and natural events. Even in very small-size island systems, environmental heterogeneity mostly contributes to species richness. Environmental heterogeneity could influence the taxocenosis structure and, ultimately, the number of species of Oniscidea via direct and indirect effects, these last mediated by area which may or may not have a direct effect on species richness.
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Olive DJ, Rathnayake RC, Haile MG. Prediction intervals for GLMs, GAMs, and some survival regression models. COMMUN STAT-THEOR M 2021. [DOI: 10.1080/03610926.2021.1887238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- David J. Olive
- School of Mathematical & Statistical Sciences, Southern Illinois University, Carbondale, Illinois, USA
| | - Rasanji C. Rathnayake
- School of Mathematical & Statistical Sciences, Southern Illinois University, Carbondale, Illinois, USA
| | - Mulubrhan G. Haile
- School of Mathematical & Statistical Sciences, Southern Illinois University, Carbondale, Illinois, USA
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A Synopsis of Sardinian Studies: Why Is it Important to Work on Island Orchids? PLANTS 2020; 9:plants9070853. [PMID: 32640731 PMCID: PMC7411895 DOI: 10.3390/plants9070853] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 11/17/2022]
Abstract
Biological and ecological investigations of islands are crucial to explain ecosystem functioning. Many studies on island biodiversity are carried out on oceanic islands. In contrast, information on continental islands, such as those in the Mediterranean Sea, is very often fragmented in space and time. Here, a synopsis of the Orchidaceae of Sardinia is presented based on literature surveys and recent botanical field studies. Our final list comprises of 64 species and 14 genera: thirteen species and subspecies were recognized as endemic and four new species were recorded for the flora of the island: Anacamptis palustris (Jacq.) R.M. Bateman, Pridgeon & M.W. Chase; Himantoglossum hircinum (L.) Spreng; Orchis italica Poir.; and Platanthera kuenkelei subsp. kuenkelei var. sardoa R.Lorenz, Akhalk., H.Baumann, Cortis, Cogoni & Scrugli. This orchid richness reflects the geological history of the island that was linked to the mainland several times, facing long periods of isolation. We also discuss a critical point-of-view of the biodiversity shortfalls still problematic for insular orchids. Indeed, within the Mediterranean Basin, the greatest amount of endemism occurs mainly on large islands, and, despite a long history of botanical exploration in European countries, many of them are scarcely investigated. This annotated synopsis shows the potential of continental islands to understand trends in ecology and evolution. Further studies are required to complete our knowledge of the orchid diversity on continental islands in order to propose scientific-based conservation programs to preserve these unique taxa.
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Naciri Y, Linder HP. The genetics of evolutionary radiations. Biol Rev Camb Philos Soc 2020; 95:1055-1072. [PMID: 32233014 DOI: 10.1111/brv.12598] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 03/12/2020] [Accepted: 03/17/2020] [Indexed: 02/06/2023]
Abstract
With the realization that much of the biological diversity on Earth has been generated by discrete evolutionary radiations, there has been a rapid increase in research into the biotic (key innovations) and abiotic (key environments) circumstances in which such radiations took place. Here we focus on the potential importance of population genetic structure and trait genetic architecture in explaining radiations. We propose a verbal model describing the stages of an evolutionary radiation: first invading a suitable adaptive zone and expanding both spatially and ecologically through this zone; secondly, diverging genetically into numerous distinct populations; and, finally, speciating. There are numerous examples of the first stage; the difficulty, however, is explaining how genetic diversification can take place from the establishment of a, presumably, genetically depauperate population in a new adaptive zone. We explore the potential roles of epigenetics and transposable elements (TEs), of neutral process such as genetic drift in combination with trait genetic architecture, of gene flow limitation through isolation by distance (IBD), isolation by ecology and isolation by colonization, the possible role of intra-specific competition, and that of admixture and hybridization in increasing the genetic diversity of the founding populations. We show that many of the predictions of this model are corroborated. Most radiations occur in complex adaptive zones, which facilitate the establishment of many small populations exposed to genetic drift and divergent selection. We also show that many radiations (especially those resulting from long-distance dispersal) were established by polyploid lineages, and that many radiating lineages have small genome sizes. However, there are several other predictions which are not (yet) possible to test: that epigenetics has played a role in radiations, that radiations occur more frequently in clades with small gene flow distances, or that the ancestors of radiations had large fundamental niches. At least some of these may be testable in the future as more genome and epigenome data become available. The implication of this model is that many radiations may be hard polytomies because the genetic divergence leading to speciation happens within a very short time, and that the divergence history may be further obscured by hybridization. Furthermore, it suggests that only lineages with the appropriate genetic architecture will be able to radiate, and that such a radiation will happen in a meta-population environment. Understanding the genetic architecture of a lineage may be an essential part of accounting for why some lineages radiate, and some do not.
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Affiliation(s)
- Yamama Naciri
- Plant Systematics and Biodiversity Laboratory, Department of Botany and Plant biology of the University of Geneva, 1 Chemin de l'Impératrice, CH-1292, Chambésy, Geneva, Switzerland
| | - H Peter Linder
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, CH-8008, Zurich, Switzerland
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Tapia PI, Negoita L, Gibbs JP, Jaramillo P. Effectiveness of water-saving technologies during early stages of restoration of endemic Opuntia cacti in the Galápagos Islands, Ecuador. PeerJ 2019; 7:e8156. [PMID: 31824769 PMCID: PMC6896940 DOI: 10.7717/peerj.8156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 11/04/2019] [Indexed: 11/20/2022] Open
Abstract
Restoration of keystone species is a primary strategy used to combat biodiversity loss and recover ecological services. This is particularly true for oceanic islands, which despite their small land mass, host a large fraction of the planet’s imperiled species. The endemic Opuntia spp. cacti are one example and a major focus for restoration in the Galápagos archipelago, Ecuador. These cacti are keystone species that support much of the unique vertebrate animal community in arid zones, yet human activities have substantially reduced Opuntia populations. Extreme aridity poses an obstacle for quickly restoring Opuntia populations though water-saving technologies may provide a solution. The aim of this study was to evaluate current restoration efforts and the utility of two water-saving technologies as tools for the early stages of restoring Opuntia populations in the Galápagos archipelago. We planted 1,425 seedlings between 2013 and 2018, of which 66% had survived by the end of 2018. Compared with no-technology controls, seedlings planted with Groasis Waterboxx® water-saving technology (polypropylene trays with water reservoir and protective refuge for germinants) had a greater rate of survival in their first two-years of growth on one island (Plaza Sur) and greater growth rate on four islands whereas the “Cocoon” water-saving technology (similar technology but made of biodegradable fiber) did not affect growth and actually reduced seedling survival. Survival and growth rate were also influenced by vegetation zone, elevation, and precipitation in ways largely contingent on island. Overall, our findings suggest that water-saving technologies are not always universally applicable but can substantially increase the survival and growth rate of seedlings in certain conditions, providing in some circumstances a useful tool for improving restoration outcomes for rare plants of arid ecosystems.
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Affiliation(s)
- Patricia Isabela Tapia
- School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne, Tyne and Wear, United Kingdom.,Charles Darwin Research Station, Charles Darwin Foundation, Santa Cruz, Galápagos, Ecuador
| | - Luka Negoita
- Charles Darwin Research Station, Charles Darwin Foundation, Santa Cruz, Galápagos, Ecuador
| | - James P Gibbs
- Department of Environmental and Forest Biology, State University of New York, Syracuse, NY, United States of America
| | - Patricia Jaramillo
- Charles Darwin Research Station, Charles Darwin Foundation, Santa Cruz, Galápagos, Ecuador.,Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
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Garcia-Retamero R, Rieskamp J. Adaptive Mechanisms for Treating Missing Information: A Simulation Study. PSYCHOLOGICAL RECORD 2017. [DOI: 10.1007/bf03395637] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Carvajal-Endara S, Hendry AP, Emery NC, Davies TJ. Habitat filtering not dispersal limitation shapes oceanic island floras: species assembly of the Galápagos archipelago. Ecol Lett 2017; 20:495-504. [PMID: 28294532 DOI: 10.1111/ele.12753] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 11/03/2016] [Accepted: 01/25/2017] [Indexed: 01/13/2023]
Abstract
Remote locations, such as oceanic islands, typically harbour relatively few species, some of which go on to generate endemic radiations. Species colonising these locations tend to be a non-random subset from source communities, which is thought to reflect dispersal limitation. However, non-random colonisation could also result from habitat filtering, whereby only a few continental species can become established. We evaluate the imprints of these processes on the Galápagos flora by analysing a comprehensive regional phylogeny for ~ 39 000 species alongside information on dispersal strategies and climatic suitability. We found that habitat filtering was more important than dispersal limitation in determining species composition. This finding may help explain why adaptive radiation is common on oceanic archipelagoes - because colonising species can be relatively poor dispersers with specific niche requirements. We suggest that the standard assumption that plant communities in remote locations are primarily shaped by dispersal limitation deserves reconsideration.
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Affiliation(s)
- Sofía Carvajal-Endara
- Department of Biology, McGill University, 1205 Ave Docteur Penfield, Montreal, QC, H3A 1B1, Canada
| | - Andrew P Hendry
- Redpath Museum, McGill University, 859 Sherbrooke Street West, Montreal, QC, H3A 2K6, Canada
| | - Nancy C Emery
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, 80309-0334, USA
| | - T Jonathan Davies
- Department of Biology, McGill University, 1205 Ave Docteur Penfield, Montreal, QC, H3A 1B1, Canada
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Collins AF, Bush MB, Sachs JP. Microrefugia and species persistence in the Galápagos highlands: a 26,000-year paleoecological perspective. Front Genet 2013; 4:269. [PMID: 24348520 PMCID: PMC3848256 DOI: 10.3389/fgene.2013.00269] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/18/2013] [Indexed: 11/13/2022] Open
Abstract
The Galápagos Islands are known to have experienced significant drought during the Quaternary. The loss of mesophytic upland habitats has been suggested to underlie the relatively lower endemism of upland compared with lowland plant assemblages. A fossil pollen record spanning the last 26,000 years from an upland bog on Santa Cruz Island, revealed the persistent presence of highland pollen and spore types during the last glacial maximum and a millennial-scale series of droughts in the mid Holocene. The absence of lowland taxa and presence of mesic taxa led to the conclusion that the highland flora of the Galápagos persisted during both these periods. The resiliency of the highland flora of the Galápagos to long-term drought contradicts an earlier hypothesis that an extinction of highland taxa occurred during the last glacial maximum and that rapid Holocene speciation created the modern plant assemblage within the last 10,000 years. Based on the palynological data, we suggest that, even during the height of glacial and Holocene droughts, cool sea-surface temperatures and strong trade-wind activity would have promoted persistent ground level cloudiness that provided the necessary moisture inputs to maintain microrefugia for mesophytic plants. Although moist conditions were maintained, the lack of precipitation caused the loss of open water habitat during such events, and accounts for the known extinctions of species such as Azolla sp., and Elatine sp., while other moisture dependent taxa, i.e., Cyathea weatherbyana, persisted.
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Affiliation(s)
- Aaron F Collins
- Department of Biological Sciences, Florida Institute of Technology Melbourne, FL, USA
| | - Mark B Bush
- Department of Biological Sciences, Florida Institute of Technology Melbourne, FL, USA
| | - Julian P Sachs
- School of Oceanography, University of Washington Seattle, WA, USA
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Olive DJ. Plots for Generalized Additive Models. COMMUN STAT-THEOR M 2013. [DOI: 10.1080/03610926.2011.628772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Simulating Species Richness Using Agents with Evolving Niches, with an Example of Galápagos Plants. INTERNATIONAL JOURNAL OF ECOLOGY 2010. [DOI: 10.1155/2010/150606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
I sought to evolve plant species richness patterns on 22 Galápagos Islands, Ecuador, as an exploration of the utility of evolutionary computation and an agent-based approach in biogeography research. The simulation was spatially explicit, where agents were plant monocultures defined by three niche dimensions, lava (yes or no), elevation, and slope. Niches were represented as standard normal curves subjected to selection pressure, where neighboring plants bred if their niches overlapped sufficiently, and were considered the same species, otherwise they were different species. Plants that bred produced seeds with mutated niches. Seeds dispersed locally and longer distances, and established if the habitat was appropriate given the seed's niche. From a single species colonizing a random location, hundreds of species evolved to fill the islands. Evolved plant species richness agreed very well with observed plant species richness. I review potential uses of an agent-based representation of evolving niches in biogeography research.
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Denslow JS, Space JC, Thomas PA. Invasive Exotic Plants in the Tropical Pacific Islands: Patterns of Diversity. Biotropica 2009. [DOI: 10.1111/j.1744-7429.2008.00469.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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BORGES PAULOAV, BROWN VALERIEK. Effect of island geological age on the arthropod species richness of Azorean pastures. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.1999.tb01897.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Newmark WD. Species-area relationship and its determinants for mammals in western North American national parks. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.1986.tb01750.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sequeira AS, Lanteri AA, Albelo LR, Bhattacharya S, Sijapati M. Colonization history, ecological shifts and diversification in the evolution of endemic Galápagos weevils. Mol Ecol 2008; 17:1089-107. [PMID: 18261050 DOI: 10.1111/j.1365-294x.2007.03642.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Mitochondrial DNA sequence data were obtained for eight species of flightless Galapaganus endemic weevils and one winged close relative in order to study their colonization history and modes of diversification in the Galápagos Archipelago. Contrary to most other insular radiations, the phylogeny estimates we recovered for Galapaganus do not follow the progression rule of island biogeography. The penalized likelihood age estimates of colonization of the archipelago exceed the age of the emerged islands and underscore the potential role of now sunken seamounts for the early evolution of Galapaganus. The phylogeny proposes one intra-island origin for Galapaganus endemics, but monophyly tests suggest a larger contribution of in-situ speciation on older islands. Generalist habitat preferences were reconstructed as ancestral while shifts to highland habitats were reconstructed as having evolved independently on different islands. Magnitudes and patterns of diversification rate were found to differ between older and younger islands. Our analyses reveal that the colonization sequence of islands and timing of colonization of Galapaganus could be linked with the geological and volcanic history of the islands in a rather complex scenario. Even though most islands appear to have been colonized soon after their emergence, there are notable deviations from the pattern of sequential colonization expected under the progression rule when considering only the extant emerged islands. Patterns of diversification rate variation on older and younger islands correspond to the volcanic activity or remnants of such activity, while the pattern of independent evolution of restricted habitat preferences in different islands suggests that habitat shifts could also have contributed to species diversity in Galapaganus.
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Affiliation(s)
- A S Sequeira
- Department of Biological Sciences, Wellesley College, Wellesley, MA 02481, USA.
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Lee MD, Cummins TDR. Evidence accumulation in decision making: Unifying the “take the best” and the “rational” models. Psychon Bull Rev 2004; 11:343-52. [PMID: 15260204 DOI: 10.3758/bf03196581] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An evidence accumulation model of forced-choice decision making is proposed to unify the fast and frugal take the best (TTB) model and the alternative rational (RAT) model with which it is usually contrasted. The basic idea is to treat the TTB model as a sequential-sampling process that terminates as soon as any evidence in favor of a decision is found and the rational approach as a sequential-sampling process that terminates only when all available information has been assessed. The unified TTB and RAT models were tested in an experiment in which participants learned to make correct judgments for a set of real-world stimuli on the basis of feedback, and were then asked to make additional judgments without feedback for cases in which the TTB and the rational models made different predictions. The results show that, in both experiments, there was strong intraparticipant consistency in the use of either the TTB or the rational model but large interparticipant differences in which model was used. The unified model is shown to be able to capture the differences in decision making across participants in an interpretable way and is preferred by the minimum description length model selection criterion.
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Affiliation(s)
- Michael D Lee
- Department of Psychology, University of Adelaide, Adelaide, SA 5005, Australia.
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Farina JM, Salazar S, Wallem KP, Witman JD, Ellis JC. Nutrient exchanges between marine and terrestrial ecosystems: the case of the Galapagos sea lion Zalophus wollebaecki. J Anim Ecol 2003. [DOI: 10.1046/j.1365-2656.2003.00760.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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GRANT BROSEMARY, GRANT PETERR. What Darwin's Finches Can Teach Us about the Evolutionary Origin and Regulation of Biodiversity. Bioscience 2003. [DOI: 10.1641/0006-3568(2003)053[0965:wdfctu]2.0.co;2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Ricklefs RE, Lovette IJ. The roles of island area per se and habitat diversity in the species-area relationships of four Lesser Antillean faunal groups. J Anim Ecol 1999. [DOI: 10.1046/j.1365-2656.1999.00358.x] [Citation(s) in RCA: 328] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Harvey LE. Spatial patterns of inter‐island plant and bird species movements in the Galápagos Islands. J R Soc N Z 1994. [DOI: 10.1080/03014223.1994.9517455] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Insular biogeography of the montane butterfly faunas in the Great Basin: comparison with birds and mammals. Oecologia 1986; 69:188-194. [DOI: 10.1007/bf00377620] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/1985] [Indexed: 10/26/2022]
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The species-area relation for archipelago biotas: Islands as samples from a species pool. POPUL ECOL 1983. [DOI: 10.1007/bf02515600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Wilcox BA. Supersaturated Island Faunas: A Species-Age Relationship for Lizards on Post-Pleistocene Land-Bridge Islands. Science 1978; 199:996-8. [PMID: 17752374 DOI: 10.1126/science.199.4332.996] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Lizard faunas on post-Pleistocene land-bridge islands in the region of Baja California were examined for the effect of island age on species diversity. Species diversity and age are significantly correlated; and when the variation in species diversity attributable to area and latitude are removed, the corrected species diversity plotted against island age produces a relaxation or extinction curve. These results provide evidence for supersaturated faunas which are relaxing to lower levels of species diversity consistent with the equilibrium theory of island biogeography.
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Abstract
Analyses of the floras of the high north Andean habitat islands (paramos) and the Galápagos Islands show that plant species diversity conforms to the MacArthur and Wilson model of island biogeography but that immigration occurred primarily during glacial periods. Modern plant species diversity is more significantly correlated with area and distance measures of the glacial forms of the islands than with similar measures of the present-day islands.
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