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Ellen E. Strong

Bio: Ellen E. Strong is an academic researcher from National Museum of Natural History. The author has contributed to research in topics: Monophyly & Cerithioidea. The author has an hindex of 21, co-authored 77 publications receiving 3525 citations. Previous affiliations of Ellen E. Strong include Humboldt University of Berlin & University of Minnesota.


Papers
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Journal ArticleDOI
TL;DR: An overview of global nonmarine molluscan biodiversity and conservation status is provided, including several case studies documenting the diversity and global decline of nonmarinemollusks.
Abstract: Invertebrate species represent more than 99% of animal diversity; however, they receive much less publicity and attract disproportionately minor research effort relative to vertebrates. Nonmarine mollusks (i.e., terrestrial and freshwater) are one of the most diverse and imperiled groups of animals, although not many people other than a few specialists who study the group seem to be aware of their plight. Nonmarine mollusks include a number of phylogenetically disparate lineages and species-rich assemblages that represent two molluscan classes, Bivalvia (clams and mussels) and Gastropoda (snails, slugs, and limpets). In this article we provide an overview of global nonmarine molluscan biodiversity and conservation status, including several case studies documenting the diversity and global decline of nonmarine mollusks. We conclude with a discussion of the roles that mollusks and malacologists should play in conservation, including research, conservation management strategies, and education and ou...

1,004 citations

Journal ArticleDOI
TL;DR: The world’s gastropod fauna from continental waters comprises ∼4,000 valid described species and a minimum of 33–38 independent lineages of Recent Neritimorpha, Caenogastropoda and Heterobranchia, but the status of the great majority of taxa is unknown, a situation that is exacerbated by a lack of experts and critical baseline data.
Abstract: The world’s gastropod fauna from continental waters comprises ∼4,000 valid described species and a minimum of 33–38 independent lineages of Recent Neritimorpha, Caenogastropoda and Heterobranchia (including the Pulmonata). The caenogastropod component dominates in terms of species richness and diversity of morphology, physiology, life and reproductive modes and has produced several highly speciose endemic radiations. Ancient oligotrophic lakes (e.g., Baikal, Ohrid, Tanganyika) are key hotspots of gastropod diversity; also noteworthy are a number of lower river basins (e.g., Congo, Mekong, Mobile Bay). But unlike many other invertebrates, small streams, springs and groundwater systems have produced the most speciose associations of freshwater gastropods. Despite their ecological importance in many aquatic ecosystems, understanding of even their systematics is discouragingly incomplete. The world’s freshwater gastropod fauna faces unprecedented threats from habitat loss and degradation and introduced fishes and other pests. Unsustainable use of ground water, landscape modification and stock damage are destroying many streams and springs in rural/pastoral areas, and pose the most significant threats to the large diversity of narrow range endemics in springs and ground water. Despite comprising only ∼5% of the world’s gastropod fauna, freshwater gastropods account for ∼20% of recorded mollusc extinctions. However, the status of the great majority of taxa is unknown, a situation that is exacerbated by a lack of experts and critical baseline data relating to distribution, abundance, basic life history, physiology, morphology and diet. Thus, the already considerable magnitude of extinction and high levels of threat indicated by the IUCN Red List of Threatened Species is certainly a significant underestimate.

440 citations

Journal ArticleDOI
TL;DR: A fully ranked, hierarchical classification summarizes recent advances in the phylogeny of the Gastropoda and Monoplacophora.
Abstract: 2,604 names at the rank of subtribe, tribe, subfamily, family and superfamily have been proposed for Recent and fossil gastropods, and another 35 for monoplacophorans. All names are listed in a nomenclator giving full bibliographical reference, date of publication, typification, and their nomenclatural availability and validity under the International Code of Zoological Nomenclature. Another 790 names, established for categories above the familygroup (infraorder to subclass) are listed separately. A fully ranked, hierarchical classification summarizes recent advances in the phylogeny of the Gastropoda and Monoplacophora. In all, the classification recognizes as valid a total of 721 gastropod families, of which 245 are known exclusively as fossils and 476 occur in the Recent with or without a fossil record; and 20 monoplacophoran families, of which 1 only occurs as Recent.Nomenclatural acts in this work: Amberleya bathonica Cox & Arkell, 1950, fixed as type species of Amberleya J. Morris & Lycett, 1851, under Art. 70.3; Ampezzopleura tenuis Nutzel, 1998, fixed as type species of Ampezzopleura Bandel, 1991, under Art. 70.3; Proserpina nitida G. B. Sowerby II, 1839, designated type species of Despoena Newton, 1891; Buccinum glabratum Linnaeus, 1758, designated type species of Dipsaccus H. Adams & A. Adams, 1853; Murex ficus Linnaeus, 1758, designated type species of Ficula Swainson, 1835; Oncomelania hupensis Gredler, 1881, designated type species of Hemibia Heude, 1890; Murex metaxa Delle Chiaje, 1828, fixed as type species of Metaxia Monterosato, 1884 under Art. 70.3; Neridomus anglicus Cox & Arkell, 1950, fixed as type species of Neridomus J. Morris & Lycett, 1851, under Art. 70.3; Navicella clypeolum Recluz, 1843, designated type species of Orthopoma Gray, 1868; Trochus viadrinus M. Schmidt, 1905, fixed as type species of Parataphrus Chavan, 1954 under Art. 70.3; Helix pomatia Linnaeus, 1758, designated type species of Pentataenia A. Schmidt, 1855; Flammulina ponsonbyi Suter, 1897, fixed as type species of Phenacohelix Suter, 1892, under Art. 70.3; Cyrtolites corniculum Eichwald, 1860, fixed as type species of Pollicina Koken, 1895, under Art. 70.3; Purpurina elegantula d'Orbigny, 1850, designated as type species of Purpurina d'Orbigny, 1850, and lectotype of Turbo bellona d'Orbigny, 1850, designated as neotype of Purpurina elegantula; Pyramidella minuscula Monterosato, 1880, fixed as type species of Tiberia Jeffreys, 1884, under Art. 70.3; Cyclostoma delicatum Philippi, 1844, fixed as type species of Trachysma G. O. Sars, 1878, under Art. 70.3; Helix elegans Gmelin, 1791, fixed as type species of Trochoidea T. Brown, 1827, under Art. 70.3; Turritellopsis stimpsoni Dall, 1919, fixed as type species of Turritellopsis G. O. Sars, 1878, under Art. 70.3; Fusus averillii Gabb, 1864, fixed as type species of Volutoderma Gabb, 1876, under Art. 70.3; Voluta pepo Lightfoot, 1786, fixed as type species of Yetus Bowdich, 1822. Curnonidae d'Udekem d'Acoz, nom. nov., and Curnon d'Udekem d'Acoz, nom. nov., are established for Charcotiidae Odhner, 1926, and Charcotia Vayssiere, 1906, (between 27 March and 1 May), non Charcotia Chevreux, 1906 (January) [Amphipoda]; Yuopisthonematidae Nutzel, nom. nov., and Yuopisthonema Nutzel, nom. nov., are established for Opisthonematidae Yu, 1976, and Opisthonema Yu, 1974, non Gill, 1862 [Pisces]. The new family-group name Burnupiidae Albrecht is established in this work; and the names Scolodontina and Orthalicoidei are first used here to denote, respectively, a suborder containing the family Scolodontidae, and an infraorder containing the superfamily Orthalicoidea.

399 citations

Journal ArticleDOI
TL;DR: Coding inapplicables as “?” (reductive coding), although flawed, is currently the best way to analyze data sets that contain inappLicable character states.

330 citations

Journal ArticleDOI
TL;DR: An analysis of the informativeness of morphological characters showed that sperm ultrastructure characters are among the best morphological features to diagnose bivalve clades, followed by characters of the shell, including its microstructure.
Abstract: To re-evaluate the relationships of the major bivalve lineages, we amassed detailed morpho-anatomical, ultrastructural and molecular sequence data for a targeted selection of exemplar bivalves spanning the phylogenetic diversity of the class. We included molecular data for 103 bivalve species (up to five markers) and also analysed a subset of taxa with four additional nuclear protein-encoding genes. Novel as well as historically employed morphological characters were explored, and we systematically disassembled widely used descriptors such as gill and stomach ‘types’. Phylogenetic analyses, conducted using parsimony direct optimisation and probabilistic methods on static alignments (maximum likelihood and Bayesian inference) of the molecular data, both alone and in combination with morphological characters, offer a robust test of bivalve relationships. A calibrated phylogeny also provided insights into the tempo of bivalve evolution. Finally, an analysis of the informativeness of morphological characters showed that sperm ultrastructure characters are among the best morphological features to diagnose bivalve clades, followed by characters of the shell, including its microstructure. Our study found support for monophyly of most broadly recognised higher bivalve taxa, although support was not uniform for Protobranchia. However, monophyly of the bivalves with protobranchiate gills was the best-supported hypothesis with incremental morphological and/or molecular sequence data. Autobranchia, Pteriomorphia, Heteroconchia, Palaeoheterodonta, Archiheterodonta, Euheterodonta, Anomalodesmata and Imparidentia new clade ( = Euheterodonta excluding Anomalodesmata) were recovered across analyses, irrespective of data treatment or analytical framework. Another clade supported by our analyses but not formally recognised in the literature includes Palaeoheterodonta and Archiheterodonta, which emerged under multiple analytical conditions. The origin and diversification of each of these major clades is Cambrian or Ordovician, except for Archiheterodonta, which diverged from Palaeoheterodonta during the Cambrian, but diversified during the Mesozoic. Although the radiation of some lineages was shifted towards the Palaeozoic (Pteriomorphia, Anomalodesmata), or presented a gap between origin and diversification (Archiheterodonta, Unionida), Imparidentia showed steady diversification through the Palaeozoic and Mesozoic. Finally, a classification system with six major monophyletic lineages is proposed to comprise modern Bivalvia: Protobranchia, Pteriomorphia, Palaeoheterodonta, Archiheterodonta, Anomalodesmata and Imparidentia.

201 citations


Cited by
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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 Article
Fumio Tajima1
30 Oct 1989-Genomics
TL;DR: It is suggested that the natural selection against large insertion/deletion is so weak that a large amount of variation is maintained in a population.

11,521 citations

Journal ArticleDOI
30 May 2014-Science
TL;DR: The biodiversity of eukaryote species and their extinction rates, distributions, and protection is reviewed, and what the future rates of species extinction will be, how well protected areas will slow extinction Rates, and how the remaining gaps in knowledge might be filled are reviewed.
Abstract: Background A principal function of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is to “perform regular and timely assessments of knowledge on biodiversity.” In December 2013, its second plenary session approved a program to begin a global assessment in 2015. The Convention on Biological Diversity (CBD) and five other biodiversity-related conventions have adopted IPBES as their science-policy interface, so these assessments will be important in evaluating progress toward the CBD’s Aichi Targets of the Strategic Plan for Biodiversity 2011–2020. As a contribution toward such assessment, we review the biodiversity of eukaryote species and their extinction rates, distributions, and protection. We document what we know, how it likely differs from what we do not, and how these differences affect biodiversity statistics. Interestingly, several targets explicitly mention “known species”—a strong, if implicit, statement of incomplete knowledge. We start by asking how many species are known and how many remain undescribed. We then consider by how much human actions inflate extinction rates. Much depends on where species are, because different biomes contain different numbers of species of different susceptibilities. Biomes also suffer different levels of damage and have unequal levels of protection. How extinction rates will change depends on how and where threats expand and whether greater protection counters them. Different visualizations of species biodiversity. ( A ) The distributions of 9927 bird species. ( B ) The 4964 species with smaller than the median geographical range size. ( C ) The 1308 species assessed as threatened with a high risk of extinction by BirdLife International for the Red List of Threatened Species of the International Union for Conservation of Nature. ( D ) The 1080 threatened species with less than the median range size. (D) provides a strong geographical focus on where local conservation actions can have the greatest global impact. Additional biodiversity maps are available at www.biodiversitymapping.org. Advances Recent studies have clarified where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. These data are increasingly accessible, bringing greater transparency to science and governance. Taxonomic catalogs of plants, terrestrial vertebrates, freshwater fish, and some marine taxa are sufficient to assess their status and the limitations of our knowledge. Most species are undescribed, however. The species we know best have large geographical ranges and are often common within them. Most known species have small ranges, however, and such species are typically newer discoveries. The numbers of known species with very small ranges are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. We expect unknown species to share these characteristics. Current rates of extinction are about 1000 times the background rate of extinction. These are higher than previously estimated and likely still underestimated. Future rates will depend on many factors and are poised to increase. Finally, although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity. Outlook Progress on assessing biodiversity will emerge from continued expansion of the many recently created online databases, combining them with new global data sources on changing land and ocean use and with increasingly crowdsourced data on species’ distributions. Examples of practical conservation that follow from using combined data in Colombia and Brazil can be found at www.savingspecies.org and www.youtube.com/watch?v=R3zjeJW2NVk.

2,360 citations

Book ChapterDOI
01 Jan 1976
TL;DR: A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in Solubility with rise in temperature.
Abstract: A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

1,573 citations

Journal ArticleDOI
TL;DR: The question, are aliens generally responsible for widespread extinctions?
Abstract: The link between species invasions and the extinction of natives is widely accepted by scientists as well as conservationists, but available data supporting invasion as a cause of extinctions are, in many cases, anecdotal, speculative and based upon limited observation. We pose the question, are aliens generally responsible for widespread extinctions? Our goal is to prompt a more critical synthesis and evaluation of the available data, and to suggest ways to take a more scientific, evidence-based approach to understanding the impact of invasive species on extinctions. Greater clarity in our understanding of these patterns will help us to focus on the most effective ways to reduce or mitigate extinction threats from invasive species.

1,390 citations