DOCSLIB.ORG

Distance Decay of Similarity Among European Urban Floras

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Distance Decay of Similarity Among European Urban Floras Global Ecology and Biogeography, (Global Ecol. Biogeogr.) (2008) 17, 363–371 Blackwell Publishing Ltd RESEARCH Distance decay of similarity among PAPER European urban floras: the impact of anthropogenic activities on β diversity Frank A. La Sorte1*, Michael L. McKinney2, Petr Pyßek3,4, Stefan Klotz5,6, G.L. Rapson7, Laura Celesti-Grapow8 and Ken Thompson9 1Division of Biological Sciences, University of ABSTRACT California, San Diego, La Jolla, CA 92093, USA, Aim We examine how two categories of non-native species (archaeophyte and 2Department of Earth and Planetary Sciences, neophyte, introduced before and after 1500, respectively) have had different University of Tennessee, Knoxville, TN 37996, β USA, 3Institute of Botany, Academy of Sciences impacts on diversity across European urban floras. Our goal is to use the unique of the Czech Republic, CZ-252 43 Pruhonice, biological perspective provided by urban areas, and the contrasting historical and Czech Republic, 4Department of Ecology, geographical perspectives provided by archaeophytes and neophytes, to infer how β Faculty of Science, Charles University, Vini4ná non-native species will impact upon diversity in the future. 7, CZ-128 01 Praha 2, Czech Republic, Location Twenty-two urban areas located in seven European countries. 5UFZ – Helmholtz Centre for Environmental Research, Department of Community Ecology Methods We used the β-sim dissimilarity index to estimate the level of β diversity (BZF), Theodor-Lieser-Strasse 4, D-06120 for 231 unique pair-wise combinations of 22 urban floras. We examined bivariate Halle, Germany, 6Virtual Institute for plots of dissimilarity by geographical separation of city centres to evaluate distance Macroecology, Theodor-Lieser-Strasse 4, decay of similarity for native species, archaeophytes and neophytes. D-06120 Halle, Germany, 7Ecology Group, Results Based on average percentages, 52.8% (SD = 8.2%) of species in the urban Institute of Natural Resources, Massey University, Palmerston North, New Zealand, floras were identified as non-native with 28.3% (SD = 6.9%) classified as neophytes 8Department of Plant Biology, Sapienza and 24.5% (SD = 4.9%) as archaeophytes. Relative to native species, across urban floras, University of Rome, Piazzale Aldo Moro 5, archaeophytes were associated with higher compositional similarity and weaker I-00185, Rome, Italy, 9Department of Animal distance decay patterns, whereas neophytes were associated with lower compositional and Plant Sciences, University of Sheffield, similarity and stronger distance decay patterns. Sheffield S10 2TN, UK Main conclusions Across European urban floras, archaeophytes and neophytes occurred in similar numbers but archaeophytes were consistently associated with lower β diversity and neophytes with higher β diversity. Thus, the impact of non-native species on β diversity can be determined, at least in part, through their historical and geographical associations with anthropogenic activities. If archaeophytes represent the long-term biogeographical outcome for human commensal species, neophytes could develop similar patterns. The consequences, however, are likely to be more substantial ecologically and geographically due to the increasing numbers of neophytes and their global anthropogenic associations. Nevertheless, at present, our findings suggest that, based on occurrence information, neophytes have not achieved this state with European urban floras retaining regionally distinct assemblages of neophytes. *Correspondence: Frank A. La Sorte, Ecology, Behavior and Evolution Section, Division of Keywords Biological Sciences, University of California, Anthropogenic activities, archaeophyte, beta diversity, biotic homogenization, San Diego, 9500 Gilman Drive, MC 0116, La Jolla, CA 92093, USA. compositional similarity, distance decay, Europe, neophyte, non-native species, E-mail: fl[email protected] urban floras. having consequences for the composition, structure and INTRODUCTION function of ecological communities (Vitousek et al., 1997; Mack Anthropogenic activities are increasingly disrupting biogeo- et al., 2000; Lockwood, 2004; Hobbs & Mooney, 2005; McNeely, graphical barriers to dispersal, resulting in the spread and 2005). Two outcomes of this process that are commonly investigated establishment of species beyond their historical ranges, thereby include changes in biological diversity within (species richness or © 2007 The Authors DOI: 10.1111/j.1466-8238.2007.00369.x Journal compilation © 2007 Blackwell Publishing Ltd www.blackwellpublishing.com/geb 363 F. A. La Sorte et al. α diversity) and among (species turnover or β diversity; in determining local patterns in urban floras (Celesti-Grapow Whittaker, 1972) species assemblages. Within assemblages at et al., 2006), habitat structure across cities tends to share many local and regional extents there is evidence that species richness commonalities that are distinct from the surrounding landscape. has increased for many taxonomic groups through the addition This island-like characteristic of urban areas makes them suitable of new species (Sax & Gaines, 2003; Sax et al., 2005). This for evaluating the broad-scale impact of the intentional and includes the addition of native and non-native species that, in unintentional translocation of species by humans. Therefore, by many cases, have benefited directly or indirectly from anthropogenic focusing on urban areas – particularly in Europe which contains activities (e.g. La Sorte & Boecklen, 2005). Among assemblages, some of the oldest and best studied examples of these environ- the outcome for β diversity is more complex and is dependent on ments (Sukopp, 2002; Antrop, 2004) – we can assess some of the a combination of factors, including the anthropogenic, biological long-term consequences of the globalization of the Earth’s biota and geographical characteristics of the region under consideration. (Vitousek et al., 1997) and the transformation of landscapes into This includes, for non-native species found within a region, their urban environments (Berry, 1990; Douglas, 1994). time of introduction and place of origin (McKinney, 2005; La In this study, we examine β diversity for native species, archaeo- Sorte & McKinney, 2006; La Sorte et al., 2007). An outcome of phytes and neophytes across 22 major urban areas located in particular interest is the broad-scale decline in β diversity associated seven European countries. We use distance decay of similarity with the loss of species with narrow distributions in conjunction (Nekola & White, 1999; McKinney, 2004; Soininen et al., 2007) with the acquisition of widely distributed species (biotic or to represent these patterns and we compare the outcome with an taxonomic homogenization; McKinney & Lockwood, 1999). analysis conducted on urban floras in the north-eastern United For vascular plants in European floras, there is evidence that States (La Sorte & McKinney, 2006). The goal of this study is to non-native species have had a different impact on β diversity use the unique biological perspective provided by European based on their time of introduction and place of origin. urban areas and the contrasting historical and geographical Specifically, across European floras, non-native species that were perspectives provided by archaeophytes and neophytes in Europe introduced before 1500 (archaeophytes) have lower β diversity, to infer how non-native species, in association with expanding and assemblages of non-native species that were introduced after anthropogenic activities, will impact upon β diversity or spatial 1500 (neophytes; see Pyßek et al., 2004a for definitions) have patterns of diversity in the future. higher β diversity (Kühn et al., 2003; Kühn & Klotz, 2006; La Sorte et al., 2007). The year 1500 signifies the initiation of MATERIALS AND METHODS European exploration of North and South America and the transition from regional (Mediterranean Basin and south- We assembled urban floras for 22 European cities located in eastern European steppes) to global (primarily North America seven countries (Fig. 1 & Table 1). Twenty-one of the cities were and Asia) origins of non-native species in Europe. Therefore, located between latitude 49° and 55° N. Rome, Italy was an contrasting patterns of β diversity for archaeophytes and outlier occurring at latitude 41° N (Fig. 1). The exclusion of neophytes reflect, at least in part, differences in their historical Rome from the analysis did not alter our conclusions, thus our and geographical associations with anthropogenic activities. analysis considered all 22 cities. For each flora, we combined all That is, archaeophytes have an ancient association functioning, varieties and subspecies into single species. We then standardized at least initially, at a regional extent, and neophytes have a modern the taxonomic nomenclature using the Missouri Botanical association functioning at a global extent. These contrasting Garden’s TROPICOS data base and the program TS, perspectives provide a unique opportunity to study the long- version 1.2 (Boyle, 2004) resulting in a data base of 4108 species. term and broad-scale impact of non-native species on β diversity. We then designated each species as native (indigenous, auto- The structure and composition of natural communities within chthonous) or non-native (non-indigenous, alien, exotic, urban areas represent the consequences of intensive anthropogenic allochthonous) within each flora (Pyßek et al., 2004a) using three activities. Specifically, urban areas act as the focal point for
Load more

Recommended publications
  • Phd Position in Ecology and Evolutionary Botany
    PhD in Biology Institut de Biologie LaborAtoire de génétique PhD position in ecology and evolutionary évolutive botany Available from February 1, 2020 INFORMATION A four-year PhD position combining ecology and evolutionary botany is available in the Laboratory of evolutionary genetics, Institute of Biology, University of Neuchâtel, Switzerland. The thesis is financed by the Swiss National Science Foundation (SNF) within the framework of a Sinergia project. It is directed by Prof. Jason Grant (UniNe) and co-supervised by Dr. Pierre-Emmanuel Du Pasquier (UniNe) and Dr. Beryl Laitung (Université de Bourgogne, UMR Agroécologie, DiJon, France). BACKGROUND AND OBJECTIVES Anthropic pressure may lead to the rapid and sometimes irreversible decline of botanical diversity, or on the contrary, favors the expansion of certain non-native species. In Europe, since the mid-20th century, the intensification and modernization of agricultural practices (mechanization with deep ploughing, use of herbicides, seed sorting, densification of monocultures and systematic use of certified seeds) has had an unprecedented impact on archaeophyte messicole species (crop-related species that were introduced mainly from the Middle East before the year 1500). As messicole species are generally therophytes (annual plants that spend the difficult season in the form of seeds), modernization quickly destroys seed stocks in the soil and contributes to the decline of these populations that were common until the mid-20th century. Although messicolous species are part of the floristic richness of the different countries where they are now native, they seem to have been introduced in the past by man in the form of seed since the domestication of crops from the Neolithic period (11000 to 9000 years ago).
    [Show full text]
  • Design a Database of Italian Vascular Alimurgic Flora (Alimurgita): Preliminary Results
    plants Article Design a Database of Italian Vascular Alimurgic Flora (AlimurgITA): Preliminary Results Bruno Paura 1,*, Piera Di Marzio 2 , Giovanni Salerno 3, Elisabetta Brugiapaglia 1 and Annarita Bufano 1 1 Department of Agricultural, Environmental and Food Sciences University of Molise, 86100 Campobasso, Italy; [email protected] (E.B.); [email protected] (A.B.) 2 Department of Bioscience and Territory, University of Molise, 86090 Pesche, Italy; [email protected] 3 Graduate Department of Environmental Biology, University “La Sapienza”, 00100 Roma, Italy; [email protected] * Correspondence: [email protected] Abstract: Despite the large number of data published in Italy on WEPs, there is no database providing a complete knowledge framework. Hence the need to design a database of the Italian alimurgic flora: AlimurgITA. Only strictly alimurgic taxa were chosen, excluding casual alien and cultivated ones. The collected data come from an archive of 358 texts (books and scientific articles) from 1918 to date, chosen with appropriate criteria. For each taxon, the part of the plant used, the method of use, the chorotype, the biological form and the regional distribution in Italy were considered. The 1103 taxa of edible flora already entered in the database equal 13.09% of Italian flora. The most widespread family is that of the Asteraceae (20.22%); the most widely used taxa are Cichorium intybus and Borago officinalis. The not homogeneous regional distribution of WEPs (maximum in the south and minimum in the north) has been interpreted. Texts published reached its peak during the 2001–2010 decade. A database for Italian WEPs is important to have a synthesis and to represent the richness and Citation: Paura, B.; Di Marzio, P.; complexity of this knowledge, also in light of its potential for cultural enhancement, as well as its Salerno, G.; Brugiapaglia, E.; Bufano, applications for the agri-food system.
    [Show full text]
  • Alien Plants in Temperate Weed Communities: Prehistoric and Recent Invaders Occupy Different Habitats
    Ecology, 86(3), 2005, pp. 772±785 q 2005 by the Ecological Society of America ALIEN PLANTS IN TEMPERATE WEED COMMUNITIES: PREHISTORIC AND RECENT INVADERS OCCUPY DIFFERENT HABITATS PETR PYSÏ EK,1,2,5 VOJTEÏ CH JAROSÏÂõK,1,2 MILAN CHYTRY ,3 ZDENEÏ K KROPA CÏ ,4 LUBOMÂõR TICHY ,3 AND JAN WILD1 1Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 PruÊhonice, Czech Republic 2Department of Ecology, Faculty of Science, Charles University, VinicÏna 7, CZ-128 01 Praha 2, Czech Republic 3Department of Botany, Masaryk University, KotlaÂrÏska 2, CZ-611 37 Brno, Czech Republic 4SlavõÂkova 16, CZ-130 00 Praha 3, Czech Republic Abstract. Variables determining the number of native and alien plants on arable land in Central Europe are identi®ed. Species richness of 698 samples of weed ¯oras recorded in the Czech Republic in plots of a standard size of 100 m2 in 1955±2000 was studied in relation to altitudinally based ¯oristic region, soil type, type of cultivated crop, climatic variables, altitude, year of the record, crop cover and height, and human population density in the region. Vascular plant species were classi®ed into native and alien, the latter divided in archaeophytes, introduced before AD 1500, and neophytes, introduced after this date. The use of minimal adequate models in the analysis of covariance allowed determination of the net effects of mutually correlated environmental variables. Models for particular species groups explained 33±48% of variation in species numbers and 27±51% in propor- tions; however, explanatory variables affected native species, archaeophytes, and neophytes differently.
    [Show full text]
  • Non-Native Plants Add to the British Flora Without Negative Consequences for Native Diversity
    Non-native plants add to the British flora without negative consequences for native diversity Chris D. Thomas1 and G. Palmer Department of Biology, University of York, York YO10 5DD, United Kingdom Edited by James H. Brown, University of New Mexico, Albuquerque, NM, and approved February 24, 2015 (received for review December 15, 2014) Plants are commonly listed as invasive species, presuming that extinctions on centennial or millennial timescales. Introduced they cause harm at both global and regional scales. Approximately plants have certainly contributed to vegetation change in many 40% of all species listed as invasive within Britain are plants. isolated environments, such as the Hawaiian Islands and the However, invasive plants are rarely linked to the national or global ecologically distinct fynbos vegetation in South Africa (10, 20– extinction of native plant species. The possible explanation is that 22). They can also become abundant in some continental competitive exclusion takes place slowly and that invasive plants regions, and hence they have the potential to alter ecosystems will eventually eliminate native species (the “time-to-exclusion hy- and exclude native species over long periods of time (23–26). We pothesis”). Using the extensive British Countryside Survey Data, refer to the proposition that ongoing increases in the dis- we find that changes to plant occurrence and cover between 1990 tributions and abundances of non-native plants will cause long- and 2007 at 479 British sites do not differ between native and term competitive exclusion of native plant species as the “time- non-native plant species. More than 80% of the plant species that to-exclusion hypothesis”.
    [Show full text]
  • Genetic Variability and Distance Between Lactuca Serriola L
    Acta Bot. Croat. 77 (2), 172–180, 2018 CODEN: ABCRA 25 DOI: 10.2478/botcro-2018-0019 ISSN 0365-0588 eISSN 1847-8476 Genetic variability and distance between Lactuca serriola L. populations from Sweden and Slovenia assessed by SSR and AFLP markers Michaela Jemelková1, Miloslav Kitner1, Eva Křístková1, Ivana Doležalová2, Aleš Lebeda1* 1 Palacký University in Olomouc, Faculty of Science, Department of Botany, Šlechtitelů 27, 783 71 Olomouc, Czech Republic 2 Department of Genetic Resources for Vegetables, Medicinal, and Special Plants of Crop Research Institute in Olomouc, Šlechtitelů 29, 783 71 Olomouc, Czech Republic Abstract – The study involved 121 samples of the common weed, Lactuca serriola L. (prickly lettuce), represent- ing 53 populations from Sweden and Slovenia. The seed materials, originating from different habitats, were re- generated and taxonomically validated at the Department of Botany, Palacký University in Olomouc, Czech Re- public. The morphological characterizations of the collected plant materials classified all 121 samples as L. serriola f. serriola; one sample was heterogeneous, and also present was L. serriola f. integrifolia. Differences in the amount and distribution of the genetic variations between the two regions were analyzed using 257 ampli- fied fragment length polymorphism (AFLP) and 7 microsatellite (SSRs) markers. Bayesian clustering and Neigh- bor-Network were used for visualization of the differences among the samples by country. Under the Bayesian approach, the best partitioning (according to the most frequent signals) was resolved into three groups. While the absence of an admixture or low admixture was detected in the Slovenian samples, and the majority of the Swedish samples, a significant admixture was detected in the profiles of five Swedish samples collected near Malmö, which bore unique morphological features of their rosette leaves.
    [Show full text]
  • Non-Native Plants Add to the British Flora Without Negative Consequences for Native Diversity
    This is a repository copy of Non-native plants add to the British flora without negative consequences for native diversity. White Rose Research Online URL for this paper: https://eprints.whiterose.ac.uk/85229/ Version: Accepted Version Article: Thomas, Chris D orcid.org/0000-0003-2822-1334 and Palmer, Georgina orcid.org/0000- 0001-6185-7583 (2015) Non-native plants add to the British flora without negative consequences for native diversity. Proceedings of the National Academy of Sciences of the United States of America. 201423995. pp. 4387-4392. ISSN 1091-6490 https://doi.org/10.1073/pnas.1423995112 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ Thomas, C. D., & Palmer, G. (2015). Non-native plants add to the British flora without negative consequences for native diversity. Proceedings of the National Academy of Sciences, USA 112 (14), 4387–4392. doi: 10.1073/pnas.1423995112 AUTHOR FINAL COPY Short title: Non-natives increase floral diversity C D Thomas1* and G Palmer1 Author affiliation: 1Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK * [email protected] Keywords: alien, biodiversity, conservation, invasive species 1 Abstract Plants are commonly listed as invasive species, presuming that they cause harm at both global and regional scales; ~40% of species listed as invasive within Britain are plants.
    [Show full text]
  • Comparison of European Archaeophyte Lists in the Light of Distribution Data
    Ecseri K and Honfi P (2020) Notulae Botanicae Horti Agrobotanici Cluj-Napoca 47(4):480-491 DOI:10.15835/nbha48111812 Notulae Botanicae Horti AcademicPres Research Article Agrobotanici Cluj-Napoca Comparison of European Archaeophyte lists in the light of distribution data Károly ECSERI 1, Péter HONFI 2* 1John von Neumann University, Faculty of Horticulture and Rural Development, Department of Horticulture, 1-3, Mészöly Gyula Square 6000, Kecskemét, Hungary; [email protected] 2Szent István University, Faculty of Horticultural Science, Institute of Sustainable Horticulture, Department of Floriculture and Dendrology, 29-43. Villányi Street, 1118, Budapest, Hungary; [email protected] (*corresponding author) Abstract Currently is not available a complex archaeophyte definition based on the same criteria in Europe, and it cause significant anomalies between neighbouring countries. The main aim of our work was to provide the criteria which based on the available lists and chorological information. For this purpose, the archaeophyte flora of 15 European countries was compared in our research. The list of available resources has been revised and completed, taking into account the distribution data of the species. The lists were merged to contain 560 species. The majority of the plants in the merged list belong to the Asteraceae and Poaceae families with 74 and 55 species, respectively. The Chenopodium genus is characterized by the most frequent occurrence (14 species). More than half of the plants are annual and 151 species belong to Eurasian geoelements. The greatest numbers of species were observed in Crete (461 species) and Greece (460 species) and the smallest numbers were observed in Ireland (240 species) and England (241 species).
    [Show full text]
  • Non-Native Plants Add to the British Flora Without Negative Consequences for Native Diversity
    Non-native plants add to the British flora without negative consequences for native diversity Chris D. Thomas1 and G. Palmer Department of Biology, University of York, York YO10 5DD, United Kingdom Edited by James H. Brown, University of New Mexico, Albuquerque, NM, and approved February 24, 2015 (received for review December 15, 2014) Plants are commonly listed as invasive species, presuming that extinctions on centennial or millennial timescales. Introduced they cause harm at both global and regional scales. Approximately plants have certainly contributed to vegetation change in many 40% of all species listed as invasive within Britain are plants. isolated environments, such as the Hawaiian Islands and the However, invasive plants are rarely linked to the national or global ecologically distinct fynbos vegetation in South Africa (10, 20– extinction of native plant species. The possible explanation is that 22). They can also become abundant in some continental competitive exclusion takes place slowly and that invasive plants regions, and hence they have the potential to alter ecosystems will eventually eliminate native species (the “time-to-exclusion hy- and exclude native species over long periods of time (23–26). We pothesis”). Using the extensive British Countryside Survey Data, refer to the proposition that ongoing increases in the dis- we find that changes to plant occurrence and cover between 1990 tributions and abundances of non-native plants will cause long- and 2007 at 479 British sites do not differ between native and term competitive exclusion of native plant species as the “time- non-native plant species. More than 80% of the plant species that to-exclusion hypothesis”.
    [Show full text]
  • The First Attempt to List the Archaeophytes of Iceland
    Acta Societatis Botanicorum Poloniae DOI: 10.5586/asbp.3608 ORIGINAL RESEARCH PAPER Publication history Received: 2018-08-09 Accepted: 2018-12-05 The frst attempt to list the archaeophytes Published: 2018-12-31 of Iceland Handling editor Michał Ronikier, W. Szafer Institute of Botany, Polish Academy of Sciences, Poland Paweł Wąsowicz* Icelandic Institue of Natural History, Akureyri Division, Borgir við Norðurslóð, Pósthólf 180, 602 Funding Akureyri, Iceland This research was funded by the Icelandic Institute of Natural * Email: [email protected] History. Competing interests No competing interests have Abstract been declared. Tis article presents for the frst time a list of the possible archaeophytes from Iceland. In the present study, all the fowering plant taxa that are considered native/long Copyright notice © The Author(s) 2018. This is an established in Iceland were assessed against criteria designed to recognize possible Open Access article distributed archaeophytes. Te assessment resulted in a list of 39 taxa meeting (or possibly under the terms of the meeting) at least one research criterion. Nineteen taxa were classifed as possible Creative Commons Attribution archaeophytes, 10 were classifed as non-natives of unknown age (due to the inability License, which permits redistribution, commercial and to classify them as neither archaeophytes nor neophytes using the available data), noncommercial, provided that while the remaining 10 species were classifed as uncertain (doubtfully native). Te the article is properly cited. limitations of the present study in terms of both the methodology and the uncertain- ties connected with the classifcation of individual taxa are discussed. Citation Wąsowicz P. The frst attempt to list the archaeophytes of Keywords Iceland.
    [Show full text]
  • Prehistory of Gardens and Biodiversity in Britain
    Prehistory of Gardens and Biodiversity in Britain By Steve Head What is a garden? In his 1755 dictionary, Dr Samuel Johnson defined a garden as: “A piece of ground, enclosed, and cultivated with extraordinary care, planted with herbs or fruit or food, or laid out for pleasure”. The key word is “enclosed” - gardens have always been patches of land set aside from the rest of the town or country, to protect and nurture the specially managed plants and animals within. Through history, gardens have had two primary functions, food (and medicinal herb) production, and places of pleasure, primarily for the rich, and often used as a conspicuous show of wealth. Climate and Human Occupation in Britain. 10 8 6 4 2 0 +2 Thousands of years BC Adapted and simplified from composite graph by Robert A. Rohde available at www.globalwarmingart.com/wiki/File:Holocene_Temperature_Variations_Rev_png Britain was probably uninhabitable at the height of the last Ice Age, around 24 - 20,000 years ago, although people survived elsewhere in Europe and Asia. The gradual warming which began about 20,000 BC was interrupted by two brief cold spells, the last one called the “Younger Dryas” from about 10,800 BC, which took Britain back to near glacial conditions, ending with permanent warming about 9,500 BC. The first people to return to Britain were the late Palaeolithic hunter-gatherers associated with Cresswell Crags in Derbyshire, about 11,000 to 9,500 BC and considered an offshoot of the southern European Magdelanian culture, famous for its cave art. After the end of the Younger Dryas, human occupation is termed Mesolithic, a nomadic or seasonally settled hunter-gatherer society adapted to temperatures similar to today.
    [Show full text]
  • The Linnaean Collections
    THE LINNEAN SPECIAL ISSUE No. 7 The Linnaean Collections edited by B. Gardiner and M. Morris WILEY-BLACKWELL 9600 Garsington Road, Oxford OX4 2DQ © 2007 The Linnean Society of London All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage or retrieval system, without permission in writing from the publisher. The designations of geographic entities in this book, and the presentation of the material, do not imply the expression of any opinion whatsoever on the part of the publishers, the Linnean Society, the editors or any other participating organisations concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The Linnaean Collections Introduction In its creation the Linnaean methodology owes as much to Artedi as to Linneaus himself. So how did this come about? It was in the spring of 1729 when Linnaeus first met Artedi in Uppsala and they remained together for just over seven years. It was during this period that they not only became the closest of friends but also developed what was to become their modus operandi. Artedi was especially interested in natural history, mineralogy and chemistry; Linnaeus on the other hand was far more interested in botany. Thus it was at this point that they decided to split up the natural world between them. Artedi took the fishes, amphibia and reptiles, Linnaeus the plants, insects and birds and, while both agreed to work on the mammals, Linneaus obligingly gave over one plant family – the Umbelliforae – to Artedi “as he wanted to work out a new method of classifying them”.
    [Show full text]
  • Alien Plants in Checklists and Floras
    53 (1) • February 2004: 131–143 Pyšek & al. • Alien plants in checklists and floras Alien plants in checklists and floras: towards better communication between taxonomists and ecologists Petr Pyšek1, David M. Richardson2, Marcel Rejmánek3, Grady L. Webster4, Mark Williamson5 & Jan Kirschner1 1 Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Prçhonice, Czech Republic. [email protected] (author for correspondence); [email protected] 2 Institute for Plant Conservation, Botany Department, University of Cape Town, Rondebosch 7701, South Africa. [email protected] 3 Section of Evolution and Ecology, University of California, Davis, California 95616, U.S.A. mrejmanek@ ucdavis.edu 4 Section of Plant Biology, University of California, Davis, California 95616, U.S.A. [email protected] 5 Department of Biology, University of York, York YO10 5DD, U.K. [email protected] The number of studies dealing with plant invasions is increasing rapidly, but the accumulating body of knowl- edge has unfortunately also spawned increasing confusion about terminology. Invasions are a global phenom- enon and comparison of geographically distant regions and their introduced biota is a crucially important methodological approach for elucidation of the determinants of invasiveness and invasibility. Comparative studies of alien floras provide substantial new insights to our understanding of general patterns of plant inva- sions. Such studies, using information in previously published floras and checklists, are fundamentally depend- ent on the quality of the assessment of particular species with respect to their taxonomic identity, time of immi- gration and invasion status. Three crucial decisions should be made when defining the status of a plant species in a given region: (1) whether the taxon is native or alien to that region (origin status); (2) what is its position in the invasion process, i.e., when was it introduced (residence status); and (3) what is the degree of its natu- ralization and possible invasion (invasion status).
    [Show full text]