Author
Peter R. Crane
Other affiliations: Swedish Museum of Natural History, University of Connecticut, Indiana University ...read more
Bio: Peter R. Crane is an academic researcher from Yale University. The author has contributed to research in topics: Pollen & Potomac Group. The author has an hindex of 66, co-authored 235 publications receiving 15690 citations. Previous affiliations of Peter R. Crane include Swedish Museum of Natural History & University of Connecticut.
Topics: Pollen, Potomac Group, Gynoecium, Cretaceous, Perianth
Papers published on a yearly basis
Papers
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TL;DR: A recent surge of interest in palaeobotanical discoveries and advances in the systematics of living plants provides a revised perspective on the evolution of early land plants and suggests new directions for future research.
Abstract: The origin and early evolution of land plants in the mid-Palaeozoic era, between about 480 and 360 million years ago, was an important event in the history of life, with far-reaching consequences for the evolution of terrestrial organisms and global environments. A recent surge of interest, catalysed by palaeobotanical discoveries and advances in the systematics of living plants, provides a revised perspective on the evolution of early land plants and suggests new directions for future research.
1,257 citations
TL;DR: New palaeobotanical discoveries and phylogenetic analyses of morphological and molecular data have clarified the initial phases of this radiation and changed the perspective on early angiosperm evolution, though important issues remain unresolved.
Abstract: The major diversification of flowering plants (angiosperms) in the Early Cretaceous, between about 130 and 90 million years ago, initiated fundamental changes in terrestrial ecosystems and set in motion processes that generated most of the extant plant diversity. New palaeobotanical discoveries, combined with recent phylogenetic analyses of morphological and molecular data, have clarified the initial phases of this radiation and changed our perspective on early angiosperm evolution, though important issues remain unresolved.
664 citations
Book•
17 Aug 1997
598 citations
Yale University1, University of Helsinki2, Imperial College London3, University of La Frontera4, Food and Agriculture Organization5, University of Kent6, Operation Wallacea7, Centre national de la recherche scientifique8, Landcare Research9, Swiss Federal Institute for Forest, Snow and Landscape Research10, Wageningen University and Research Centre11, University of Hamburg12, Masaryk University13, Oeschger Centre for Climate Change Research14, University of Bayreuth15, University of Göttingen16, Lancaster University17, Peking University18
TL;DR: This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate, and the globalNumber of trees has fallen by approximately 46% since the start of human civilization.
Abstract: The global extent and distribution of forest trees is central to our understanding of the terrestrial biosphere. We provide the first spatially continuous map of forest tree density at a global scale. This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate. Of these trees, approximately 1.39 trillion exist in tropical and subtropical forests, with 0.74 trillion in boreal regions and 0.61 trillion in temperate regions. Biome-level trends in tree density demonstrate the importance of climate and topography in controlling local tree densities at finer scales, as well as the overwhelming effect of humans across most of the world. Based on our projected tree densities, we estimate that over 15 billion trees are cut down each year, and the global number of trees has fallen by approximately 46% since the start of human civilization.
542 citations
541 citations
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TL;DR: A revised and updated classification for the families of the flowering plants is provided in this paper, which includes Austrobaileyales, Canellales, Gunnerales, Crossosomatales and Celastrales.
7,299 citations
BirdLife International1, United Nations Environment Programme2, Zoological Society of London3, Statistics Netherlands4, University of North Carolina at Chapel Hill5, Old Dominion University6, Conservation International7, Food and Agriculture Organization8, University of Virginia9, Royal Society for the Protection of Birds10, University of Queensland11, University of Cambridge12, National Center for Atmospheric Research13, World Wide Fund for Nature14, South African National Parks15, UNESCO16, University of British Columbia17, Tata Institute of Fundamental Research18, The Nature Conservancy19, Patuxent Wildlife Research Center20, American Bird Conservancy21, Stellenbosch University22, International Union for Conservation of Nature and Natural Resources23
TL;DR: Most indicators of the state of biodiversity showed declines, with no significant recent reductions in rate, whereas indicators of pressures on biodiversity showed increases, indicating that the Convention on Biological Diversity’s 2010 targets have not been met.
Abstract: In 2002, world leaders committed, through the Convention on Biological Diversity, to achieve a significant reduction in the rate of biodiversity loss by 2010. We compiled 31 indicators to report on progress toward this target. Most indicators of the state of biodiversity (covering species' population trends, extinction risk, habitat extent and condition, and community composition) showed declines, with no significant recent reductions in rate, whereas indicators of pressures on biodiversity (including resource consumption, invasive alien species, nitrogen pollution, overexploitation, and climate change impacts) showed increases. Despite some local successes and increasing responses (including extent and biodiversity coverage of protected areas, sustainable forest management, policy responses to invasive alien species, and biodiversity-related aid), the rate of biodiversity loss does not appear to be slowing.
3,993 citations
TL;DR: A high-quality draft of the genome sequence of grapevine is obtained from a highly homozygous genotype, revealing the contribution of three ancestral genomes to the grapevine haploid content and explaining the chronology of previously described whole-genome duplication events in the evolution of flowering plants.
Abstract: The analysis of the first plant genomes provided unexpected evidence for genome duplication events in species that had previously been considered as true diploids on the basis of their genetics. These polyploidization events may have had important consequences in plant evolution, in particular for species radiation and adaptation and for the modulation of functional capacities. Here we report a high-quality draft of the genome sequence of grapevine (Vitis vinifera) obtained from a highly homozygous genotype. The draft sequence of the grapevine genome is the fourth one produced so far for flowering plants, the second for a woody species and the first for a fruit crop (cultivated for both fruit and beverage). Grapevine was selected because of its important place in the cultural heritage of humanity beginning during the Neolithic period. Several large expansions of gene families with roles in aromatic features are observed. The grapevine genome has not undergone recent genome duplication, thus enabling the discovery of ancestral traits and features of the genetic organization of flowering plants. This analysis reveals the contribution of three ancestral genomes to the grapevine haploid content. This ancestral arrangement is common to many dicotyledonous plants but is absent from the genome of rice, which is a monocotyledon. Furthermore, we explain the chronology of previously described whole-genome duplication events in the evolution of flowering plants.
3,311 citations
TL;DR: This work states that the distribution of biodiversity across the Earth can be described in terms of a relatively small number of broad-scale spatial patterns, and theory is developing rapidly, improving in its internal consistency, and more readily subjected to empirical challenge.
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.
2,859 citations
TL;DR: Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed >65% of seagrass and wetland habitat, degraded water quality, and accelerated species invasions.
Abstract: Estuarine and coastal transformation is as old as civilization yet has dramatically accelerated over the past 150 to 300 years. Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed >65% of seagrass and wetland habitat, degraded water quality, and accelerated species invasions. Twentieth-century conservation efforts achieved partial recovery of upper trophic levels but have so far failed to restore former ecosystem structure and function. Our results provide detailed historical baselines and quantitative targets for ecosystem-based management and marine conservation.
2,795 citations