13 research outputs found
Habitat availability and heterogeneity and the Indo-Pacific warm pool as predictors of marine species richness in the tropical Indo-Pacific
Range overlap patterns were observed in a dataset of 10,446 expert-derived marine species distribution maps, including 8,295 coastal fishes, 1,212 invertebrates (crustaceans and molluscs), 820 reef-building corals, 50 seagrasses and 69 mangroves. Distributions of tropical Indo-Pacific shore fishes revealed a concentration of species richness in the northern apex and central region of the Coral Triangle epicenter of marine biodiversity. This pattern was supported by distributions of invertebrates and habitat-forming primary producers. Habitat availability, heterogeneity and sea surface temperatures were highly correlated with species richness across spatial grains ranging from 23,000 to 5,100,000 km2 with and without correction for autocorrelation. The consistent retention of habitat variables in our predictive models supports the area of refuge hypothesis which posits reduced extinction rates in the Coral Triangle. This does not preclude support for a center of origin hypothesis that suggests increased speciation in the region may contribute to species richness. In addition, consistent retention of sea surface temperatures in models suggests that available kinetic energy may also be an important factor in shaping patterns of marine species richness. Kinetic energy may hasten rates of both extinction and speciation. The position of the Indo-Pacific Warm Pool to the east of the Coral Triangle in central Oceania and a pattern of increasing species richness from this region into the central and northern parts of the Coral Triangle suggests peripheral speciation with enhanced survival in the cooler parts of the Coral Triangle that also have highly concentrated available habitat. These results indicate that conservation of habitat availability and heterogeneity is important to reduce extinction and that changes in sea surface temperatures may influence the evolutionary potential of the region
An Overview of Marine Biodiversity in United States Waters
Marine biodiversity of the United States (U.S.) is extensively documented, but data assembled by the United States National Committee for the Census of Marine Life demonstrate that even the most complete taxonomic inventories are based on records scattered in space and time. The best-known taxa are those of commercial importance. Body size is directly correlated with knowledge of a species, and knowledge also diminishes with distance from shore and depth. Measures of biodiversity other than species diversity, such as ecosystem and genetic diversity, are poorly documented. Threats to marine biodiversity in the U.S. are the same as those for most of the world: overexploitation of living resources; reduced water quality; coastal development; shipping; invasive species; rising temperature and concentrations of carbon dioxide in the surface ocean, and other changes that may be consequences of global change, including shifting currents; increased number and size of hypoxic or anoxic areas; and increased number and duration of harmful algal blooms. More information must be obtained through field and laboratory research and monitoring that involve innovative sampling techniques (such as genetics and acoustics), but data that already exist must be made accessible. And all data must have a temporal component so trends can be identified. As data are compiled, techniques must be developed to make certain that scales are compatible, to combine and reconcile data collected for various purposes with disparate gear, and to automate taxonomic changes. Information on biotic and abiotic elements of the environment must be interactively linked. Impediments to assembling existing data and collecting new data on marine biodiversity include logistical problems as well as shortages in finances and taxonomic expertise
Exploring novel taxonomic character sets in the Mollusca : the Cribrarula cribraria complex (Gastropoda:Cypraeidae) as a case study
Thesis (Ph. D.)--University of Hawaii at Manoa, 2003.Includes bibliographical references (leaves 302-323).Mode of access: World Wide Web.Also available by subscription via World Wide Webxxvii, 323 leaves ill., maps 29 cm. +The goal of this dissertation is to explore novel and non-traditional taxonomic characters that may be useful for mollusks, and combine them with radular and shell characters to carry out a taxonomic review of the genus Cribrarula (Cypraeidae). Shells in this genus have conspicuous dorsal spots, but like odler cowries, lack sculpture, spines, and other shell characters commonly used in gastropod taxonomy. For these reasons, cowrie shells are considered uninformative. The study of dorsal spots (DS) and related characters suggest that at least in this complex, the dorsal spots may represent a record of the mantle papillae. If the hypothesis is correct, then DS may provide information on the soft parts that previously was only available from the study of live or preserved specimens. Each species in the complex has a species-specific range of DS, marginal spots, and allied characters, thus suggesting that they may be useful in distinguishing species in the complex. The odontophore cartilage provides support for the radula and attachment for the muscles responsible for feeding. Although intimately connected to the radula and known since the 1800's, the taxonomic value of the odontophore has been overlooked. A study of odontophore variation in the family Cypraeidae proposes the structure as a novel taxonomic character, potentially applicable to most mollusks. The Cribrarula cribraria Linnaeus, 1758 complex is reviewed, and twelve species and six subspecies are recognized on the basis of multivariate analyses of shell characters, the radula, odontophore, and geographic distribution. The shell, radula, odontophore and distributional maps are illustrated for each taxon. The nominal species, cribraria, ranges from East Africa to the Central Pacific, and several populations are distinctive enough to be recognized as subspecies. The other eleven species are restricted to narrower ranges along the periphery of the distribution of cribraria. During the review of Cribrarula, a new species from New South Wales was described as C. gravida Moretzsohn, 2002
Extending Marine Species Distribution Maps Using Non-Traditional Sources
Extending Marine Species Distribution Maps Using Non-Traditional Source
Distribution pattern of the different parameters in the Indo-Pacific using UTM grid.
<p>The grids were classified (equal interval) into 10 classes based on the amount of shallow water area recorded in each cell such that cells in red have the largest parameter value, and cells in blue have the lowest parameter value. Cells with zero values are not displayed. (A) Extent of coastline (km), (B) Habitat heterogeneity index using area (HDIa), (C) Habitat heterogeneity index using number (HDIn), (D) Sea surface temperature (SST), (E) Net primary productivity (NPP).</p
Significant single-predictor Generalized Linear Model (GLM) and Spatial Linear Model (SLM) for species richness.
<p>Actual <i>R</i><sup>2</sup> and pseudo-<i>R</i><sup>2</sup> values can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056245#pone.0056245.s017" target="_blank">Table S4</a>. The predictors are shallow water area (SW), coastline length (CL), habitat diversity based on area (HDIa), habitat diversity based on number of patches (HDIn), sea surface temperature (SST), and net primary productivity (NPP). Asterisks indicate significance value of P:</p>*<p>(<0.05),</p>**<p>(<0.01);</p>***<p>(<0.001); ns (not significant).</p><p>Grid sizes are as follows: Small = 23,000 km<sup>2</sup>; Medium = 92,000 km<sup>2</sup>; Large = 368,000 km<sup>2</sup>; UTM = 617,000 km<sup>2</sup>; Extra large = 1,470,000 km<sup>2</sup>; Largest = 5,100,000 km<sup>2</sup>. The significance value with the highest adjusted <i>R<sup>2</sup></i> and pseudo-<i>R<sup>2</sup></i> is highlighted in boldface.</p
Distribution pattern of shallow water area extent in the Indo-Pacific at different grid scales.
<p>The grids were classified into 10 equal interval classes based on the amount of shallow water area recorded in each cell such that cells in red have the largest amount of shallow water area, and cells in blue have the lowest amount of shallow water area. Cells with zero values are not displayed. (A) Small grid, (B) Medium grid, (C) Large grid, (d) UTM grid, (E) Extra large grid, (F) Largest grid.</p
Patterns of species richness from range overlap raster data from 10,446 species.
<p>Each change in color represents an increase or decrease of 82 species (40 total classes or a 2.5% change per class). (A) Pattern of species distribution in the entire Indo-Pacific region. The top 10% for the highest species richness is found in the Coral Triangle (marked in red, pink, and yellow in panel B, with decreasing increments of species richness indicated by lighter shades), and the remaining decreasing increments of total species richness are indicated by lighter shades of blue, (B) The top 10% (shades of red), 20% (dark yellow) and 30% (light yellow) of concentration of species is in the Coral Triangle, with Philippines as the epicenter, (C) All fishes showing the top 1% of species richness (white); (D) Molluscs and crustaceans showing the top 10% of species richness (shades of red); (E) Habitat-forming species (corals, seagrasses, and mangroves) showing the top 10% of species richness (shades of red).</p
Species richness and mean SST versus latitude or longitude at different grid scales.
<p>(A) Latitude at small grid, (B) Latitude at UTM grid, (C) Longitude at small grid, (D) Longitude at UTM grid. Latitudinal peaks of species richness (blue circle) are shown along the 10–20° north and latitudinal peaks in mean SST values (°C) (red triangle) are along the 10–20° south. Longitudinal peaks of species richness (blue circle) are located in the 120° east while longitudinal peaks in mean SST values (°C) (red triangle) are found along the 130–150° east.</p