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John Dransfield

Bio: John Dransfield is an academic researcher from Royal Botanic Gardens. The author has contributed to research in topics: Calamus & Arecaceae. The author has an hindex of 38, co-authored 142 publications receiving 7497 citations.
Topics: Calamus, Arecaceae, Calamoideae, Genus, Rattan


Papers
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Journal ArticleDOI
TL;DR: Part 1 What are tropical rain forests?

1,036 citations

Journal ArticleDOI
Jens Kattge1, Gerhard Bönisch2, Sandra Díaz3, Sandra Lavorel  +751 moreInstitutions (314)
TL;DR: The extent of the trait data compiled in TRY is evaluated and emerging patterns of data coverage and representativeness are analyzed to conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements.
Abstract: Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.

882 citations

Journal ArticleDOI
TL;DR: This classic book, now revised and expanded to include the latest information on plant morphology, more than 1000 exquisite line drawings including 119 that are new to this edition, and nearly twice as many photographs as the previous edition is remarkable for its user-friendly organization, high-quality illustrations, and extensive cross-referencing.
Abstract: The diverse external shapes and structures that make up flowering plants can be bewildering and even daunting, as can the terminology used to describe them. An understanding of plant form - plant morphology - is essential to appreciating the wonders of the plant world and to the study of botany and horticulture at every level. In this ingeniously designed volume, the complex subject becomes both accessible and manageable. The first part of the book describes and clearly illustrates the major plant structures that can be seen with the naked eye or a hand lens: leaf, root, stem, reproductive organs, and seedlings; special sections focus on vegetative propagation, and the morphology of grasses, orchids, and cacti. However, plants are dynamic organisms, constantly growing, changing, and becoming more elaborate, and understanding the development of a plant or plant part is as important as describing its final form. Part II focuses on how plants grow: bud development, the growth of reproductive organs, leaf arrangement, branching patterns, and the accumulation and loss of structures. This classic book, now revised and expanded to include the latest information on plant morphology, more than 1000 exquisite line drawings including 119 that are new to this edition, and nearly twice as many photographs as the previous edition, is remarkable for its user-friendly organization, high-quality illustrations, and extensive cross-referencing. Aimed at students of botany and horticulture, enthusiastic gardeners and amateur naturalists, it functions as an illustrated dictionary, a basic course in plant morphology, and an intriguing and enlightening book to dip into.

532 citations

DOI
01 Jan 2008
TL;DR: In the new edition, genus treatments include complete descriptions, nomenclature, etymology and discussions of diversity, distribution, phylogeny, morphology, uses and ecology, as well as providing essential background information to the classification presented within the book.
Abstract: Genera Palmarum - The Evolution and Classification of the Palms is the standard reference work for information on the biology of the palm family, especially evolution, systematics, structure, fossil record and classification. Genera Palmarum - The Evolution and Classification of Palms is a completely rewritten edition of the acclaimed standard reference work for the palm family, a group of plants of immense economic and horticultural significance. In the new edition, genus treatments include complete descriptions, nomenclature, etymology and discussions of diversity, distribution, phylogeny, morphology, uses and ecology. All genera of palms are illustrated with analytical plates, maps and numerous photographs, mostly taken in the wild. The introduction consists of essays on the structure of palms, their pollen, cytology, chemistry, fossil record, evolution, phylogeny, natural history and biogeography, providing essential background information to the classification presented within the book. The classification itself is substantially revised and based on the latest phylogenetic evidence. Since the first edition, published in 1987, several new genera have been discovered and the wealth of new research into the phylogeny of palms has revealed relationships not appreciated in the past, resulting in substantial reorganization of subfamilies, tribes, subtribes and genera. An illustrated glossary and geographical listings complete this essential reference book to the palm family. Winner of the 2009 Technical category CBHL (The Council on Botanical and Horticultural Libraries) Annual Award for a Significant Work in Botanical or Horticultural Literature.

483 citations

Journal ArticleDOI
11 Apr 2008-Science
TL;DR: It is shown, in an analysis of wide taxonomic and geographic breadth and high spatial resolution, that multitaxonomic rather than single-taxon approaches are critical for identifying areas likely to promote the persistence of most species.
Abstract: Globally, priority areas for biodiversity are relatively well known, yet few detailed plans exist to direct conservation action within them, despite urgent need. Madagascar, like other globally recognized biodiversity hot spots, has complex spatial patterns of endemism that differ among taxonomic groups, creating challenges for the selection of within-country priorities. We show, in an analysis of wide taxonomic and geographic breadth and high spatial resolution, that multitaxonomic rather than single-taxon approaches are critical for identifying areas likely to promote the persistence of most species. Our conservation prioritization, facilitated by newly available techniques, identifies optimal expansion sites for the Madagascar government's current goal of tripling the land area under protection. Our findings further suggest that high-resolution multitaxonomic approaches to prioritization may be necessary to ensure protection for biodiversity in other global hot spots.

477 citations


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Journal ArticleDOI
24 Feb 2000-Nature
TL;DR: A ‘silver bullet’ strategy on the part of conservation planners, focusing on ‘biodiversity hotspots’ where exceptional concentrations of endemic species are undergoing exceptional loss of habitat, is proposed.
Abstract: Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify 'biodiversity hotspots' where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a 'silver bullet' strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the world's species at risk.

24,867 citations

Journal ArticleDOI
TL;DR: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols used xiii 1.
Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

14,171 citations

Journal ArticleDOI
TL;DR: It is shown that when an individual dies, it may or may not be replaced by an individual of the same species, which is all‐important to the argument presented.
Abstract: SUMMARY 1According to ‘Gause's hypothesis’ a corollary of the process of evolution by natural selection is that in a community at equilibrium every species must occupy a different niche. Many botanists have found this idea improbable because they have ignored the processes of regeneration in plant communities. 2Most plant communities are longer-lived than their constituent individual plants. When an individual dies, it may or may not be replaced by an individual of the same species. It is this replacement stage which is all-important to the argument presented. 3Several mechanisms not involving regeneration also contribute to the maintenance of species-richness: (a). differences in life-form coupled with the inability of larger plants to exhaust or cut off all resources, also the development of dependence-relationships, (b) differences in phenology coupled with tolerance of suppression, (c) fluctuations in the environment coupled with relatively small differences in competitive ability between many species, (d) the ability of certain species-pairs to form stable mixtures because of a balance of intraspecific competition against interspecific competition, (e) the production of substances more toxic to the producer-species than to the other species, (f) differences in the primary limiting mineral nutrients or pore-sizes in the soil for neighbouring plants of different soecies, and (g) differences in the competitive abilities of species dependent on their physiological age coupled with the uneven-age structure of many populations. 4The mechanisms listed above do not go far to explain the indefinite persistence in mixture of the many species in the most species-rich communities known. 5In contrast there seem to be almost limitless possibilities for differences between species in their requirements for regeneration, i.e. the replacement of the individual plants of one generation by those of the next. This idea is illustrated for tree species and it is emphasized that foresters were the first by a wide margin to appreciate its importance. 6The processes involved in the successful invasion of a gap by a given plant species and some characters of the gap that may be important are summarized in Table 2. 7The definition of a plant's niche requires recognition of four components: (a) the habitat niche, (b) the life-form niche, (c) the phenological niche, and (d) the regeneration niche. 8A brief account is given of the patterns of regeneration in different kinds of plant community to provide a background for studies of differentiation in the regeneration niche. 9All stages in the regeneration-cycle are potentially important and examples of differentiation between species are given for each of the following stages: (a) Production of viable seed (including the sub-stages of flowering, pollination and seed-set), (b) dispersal, in space and time, (c) germination, (d) establishment, and (e) further development of the immature plant. 10In the concluding discussion emphasis is placed on the following themes: (a) the kinds of work needed in future to prove or disprove that differentiation in the regeneration niche is the major explanation of the maintenance of species-richness in plant communities, (b) the relation of the present thesis to published ideas on the origin of phenological spread, (c) the relevance of the present thesis to the discussion on the presence of continua in vegetation, (d) the co-incidence of the present thesis and the emerging ideas of evolutionists about differentiation of angiosperm taxa, and (e) the importance of regeneration-studies for conservation.

4,057 citations

Journal ArticleDOI
TL;DR: In this article, the authors propose case studies on various topics to identify management practices, technologies and policies that promote the positive and mitigate the negative impacts of agriculture on biodiversity, and enhance productivity and the capacity to sustain livelihoods.
Abstract: Background The programme of work on agricultural biodiversity, adopted by the Conference of Parties in decision V/5, makes provision for case studies on various topics to identify management practices, technologies and policies that promote the positive and mitigate the negative impacts of agriculture on biodiversity, and enhance productivity and the capacity to sustain livelihoods. More specifically, activity 2.1 of the Programme of Work calls for a series of case studies, in a range of environments and production systems, and in each region: (a) To identify key goods and services provided by agricultural biodiversity, needs for the conservation and sustainable use of components of this biological diversity in agricultural ecosystems, and threats to such diversity;

2,990 citations

Journal ArticleDOI
TL;DR: The results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines and Me- soamerica, Sundaland, Indo-Burma, Madagascar, and Choco-Darien-Western Ecuador will lose the most habitat in the near future.
Abstract: Nearly half the world's vascular plant species and one-third of terrestrial vertebrates are endemic to 25 "hotspots" of biodiversity, each of which has at least 1500 endemic plant species. None of these hotspots have more than one-third of their pristine habitat remaining. Historically, they covered 12% of the land's sur- face, but today their intact habitat covers only 1.4% of the land. As a result of this habitat loss, we expect many of the hotspot endemics to have either become extinct or—because much of the habitat loss is recent— to be threatened with extinction. We used World Conservation Union (IUCN) Red Lists to test this expectation. Overall, between one-half and two-thirds of all threatened plants and 57% of all threatened terrestrial verte- brates are hotspot endemics. For birds and mammals, in general, predictions of extinction in the hotspots based on habitat loss match numbers of species independently judged extinct or threatened. In two classes of hotspots the match is not as close. On oceanic islands, habitat loss underestimates extinction because intro- duced species have driven extinctions beyond those caused by habitat loss on these islands. In large hotspots, conversely, habitat loss overestimates extinction, suggesting scale dependence (this effect is also apparent for plants). For reptiles, amphibians, and plants, many fewer hotspot endemics are considered threatened or ex- tinct than we would expect based on habitat loss. This mismatch is small in temperate hotspots, however, sug- gesting that many threatened endemic species in the poorly known tropical hotspots have yet to be included on the IUCN Red Lists. We then asked in which hotspots the consequences of further habitat loss (either abso- lute or given current rates of deforestation) would be most serious. Our results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines, Me- soamerica, Sundaland, Indo-Burma, Madagascar, and Choco-Darien-Western Ecuador will lose the most spe- cies in the near future. Without urgent conservation intervention, we face mass extinctions in the hotspots.

1,798 citations