Author
Peter A. Jumars
Other affiliations: University of Southern California, University of Washington, Scripps Institution of Oceanography ...read more
Bio: Peter A. Jumars is an academic researcher from University of Maine. The author has contributed to research in topics: Benthic zone & Sediment. The author has an hindex of 64, co-authored 137 publications receiving 13161 citations. Previous affiliations of Peter A. Jumars include University of Southern California & University of Washington.
Topics: Benthic zone, Sediment, Population, Sediment transport, Settling
Papers published on a yearly basis
Papers
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01 Jan 1979
TL;DR: A review of the eating habits of polychaetes can be found in this article, where the polychaete families are arranged in alphabetical order and the feeding habits of each are summarized.
Abstract: Current information on the eating habits of polychaetes are reviewed. The polychaete families are arranged in alphabetical order and the feeding habits of each are summarized. Feeding guilds are defined based on a joint consideration of food, eating habits, and locomotory patterns. An understanding of the sympatric occurrance in the deep sea of several congeners with extremely limited morphological differentiation was of particular interest. This review contains 355 references, 23 figures, and 33 tables.
1,775 citations
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509 citations
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01 Apr 1989TL;DR: In this paper, a new extension of digestion theory and reinterpretation of published empirical evidence suggest that the principal pathway of dissolved organic carbon (DOC) from phytoplankton to bacteria is through the byproducts of animal ingestion and digestion rather than via excretion of DOC directly from intact phyto-ankton.
Abstract: A new extension of digestion theory and re-interpretation of published empirical evidence suggest that the principal pathway of dissolved organic carbon (DOC) from phytoplankton to bacteria is through the byproducts of animal ingestion and digestion rather than via excretion of DOC directly from intact phytoplankton. Simple model calculations reveal that for a substance with diffusion coefficient equalling 10−5 cm2 s−1, excess (over ambient) concentrations of solute in a fecal pellet of typical size (diam. ⩽ 1 mm) are lost rapidly; ⩾ 50% of any excess is diffused out of the pellet within 5 min—even in a stagnant water column and without particle sinking. Reasons for rapid loss and its insensitivity to fluid dynamic conditions are small size of the pelletal reservoir and the sharp concentration gradient between pelletal and ambient concentrations upon pellet release. As a consequence, most solutes initially contained in fecal pellets of zooplankton generally will remain in the 10–100 m thick water layer within which the pellets initially are deposited. Focus on animal-caused organic release over these very short time scales may help to resolve some of the growing paradoxes of DOC standing stocks and fluxes in the upper ocean.
490 citations
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TL;DR: Polychaetes are common in most marine habitats and dominate many infaunal communities and now include osmotrophic siboglinids as well as sipunculans, echiurans, and myzostomes, which molecular genetic analyses have placed within Annelida.
Abstract: Polychaetes are common in most marine habitats and dominate many infaunal communities. Functional guild classification based on taxonomic identity and morphology has linked community structure to ecological function. The functional guilds now include osmotrophic siboglinids as well as sipunculans, echiurans, and myzostomes, which molecular genetic analyses have placed within Annelida. Advances in understanding of encounter mechanisms explicitly relate motility to feeding mode. New analyses of burrowing mechanics explain the prevalence of bilateral symmetry and blur the boundary between surface and subsurface feeding. The dichotomy between microphagous deposit and suspension feeders and macrophagous carnivores, herbivores, and omnivores is further supported by divergent digestive strategies. Deposit feeding appears to be limited largely to worms longer than 1 cm, with juveniles and small worms in general restricted to ingesting highly digestible organic material and larger, rich food items, blurring the macrophage-microphage dichotomy that applies well to larger worms.
444 citations
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TL;DR: In this paper, velocity and turbulence intensity profiles were measured at 3 free-stream flow velocities (5.5, 10 and 20 cm S-'), at 5 shoot densities (1200, 1000, 800, 600 and 400 shoots rne2), and at 5 along-stream positions relative to the leading edge of the eelgrass bed.
Abstract: Flow dynamics in Zostera marina L. (eelgrass) were studied in a large seawater flume. Velocity and turbulence intensity profiles were measured at 3 free-stream flow velocities (5. 10 and 20 cm S-'), at 5 shoot densities (1200, 1000,800, 600 and 400 shoots rne2), and at 5 along-stream positions relative to the leading edge of the eelgrass bed (10 cm upstream of the bed; 25, 50, 75 and 100 cm downstream of the leading edge of the bed). All the profiles (75) above the canopy or over bare sand fitted a log-profile relationship. At all densities and ambient velocities tested, mean velocity increased above the canopy, while within the bed water speed dropped distinctly below the canopy-water interface. Depending on shoot density, water speed was from 2 to 10 times lower under the canopy than upstream of the seagrass bed. Shear velocities (U%) above the canopy were 2 to 11 times greater than outside the bed at equivalent height, and Increased significantly with distance into the meadow. No significant differences among dens~ties were observed. Turbulence intensity showed a dramatic increase in all the profiles at the canopy-water interface, a significant increase with distance into the bed, but showed no significant differences between densities. Fluid flux within the bed decreased significantly with distance into the meadow, but exhibited no significant dependence on density. Downstream, vertically integrated fluid flux at 100 cm into the bed ranged between 14.7 and 40.6 O/O of upstream values. The least flux reduction occurred at the highest velocity (20 cm S-'). Trends in shear velocity and turbulence intensity show clearly that within the bed one can distinguish 2 dynamically different environments. The 'canopy-water interface' habitat 1s characterized by high shear stress and high turbulence intensity; the 'below-canopy' habitat is characterized by low shear stress and a reduction of turbulence intensity.
444 citations
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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
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TL;DR: This work has developed a quantitative theory for how metabolic rate varies with body size and temperature, and predicts how metabolic theory predicts how this rate controls ecological processes at all levels of organization from individuals to the biosphere.
Abstract: Metabolism provides a basis for using first principles of physics, chemistry, and biology to link the biology of individual organisms to the ecology of populations, communities, and ecosystems. Metabolic rate, the rate at which organisms take up, transform, and expend energy and materials, is the most fundamental biological rate. We have developed a quantitative theory for how metabolic rate varies with body size and temperature. Metabolic theory predicts how metabolic rate, by setting the rates of resource uptake from the environment and resource allocation to survival, growth, and reproduction, controls ecological processes at all levels of organization from individuals to the biosphere. Examples include: (1) life history attributes, including devel- opment rate, mortality rate, age at maturity, life span, and population growth rate; (2) population interactions, including carrying capacity, rates of competition and predation, and patterns of species diversity; and (3) ecosystem processes, including rates of biomass production and respiration and patterns of trophic dynamics. Data compiled from the ecological literature strongly support the theoretical predictions. Even- tually, metabolic theory may provide a conceptual foundation for much of ecology, just as genetic theory provides a foundation for much of evolutionary biology.
6,017 citations
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TL;DR: The nervous system seems to combine visual and haptic information in a fashion that is similar to a maximum-likelihood integrator, and this model behaved very similarly to humans in a visual–haptic task.
Abstract: When a person looks at an object while exploring it with their hand, vision and touch both provide information for estimating the properties of the object. Vision frequently dominates the integrated visual-haptic percept, for example when judging size, shape or position, but in some circumstances the percept is clearly affected by haptics. Here we propose that a general principle, which minimizes variance in the final estimate, determines the degree to which vision or haptics dominates. This principle is realized by using maximum-likelihood estimation to combine the inputs. To investigate cue combination quantitatively, we first measured the variances associated with visual and haptic estimation of height. We then used these measurements to construct a maximum-likelihood integrator. This model behaved very similarly to humans in a visual-haptic task. Thus, the nervous system seems to combine visual and haptic information in a fashion that is similar to a maximum-likelihood integrator. Visual dominance occurs when the variance associated with visual estimation is lower than that associated with haptic estimation.
4,142 citations
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TL;DR: Global plastics production and the accumulation of plastic waste are documented, showing that trends in mega- and macro-plastic accumulation rates are no longer uniformly increasing and that the average size of plastic particles in the environment seems to be decreasing.
Abstract: One of the most ubiquitous and long-lasting recent changes to the surface of our planet is the accumulation and fragmentation of plastics. Within just a few decades since mass production of plastic...
4,044 citations
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TL;DR: The paper discusses first how autocorrelation in ecological variables can be described and measured, and ways are presented of explicitly introducing spatial structures into ecological models, and two approaches are proposed.
Abstract: ilbstract. Autocorrelation is a very general statistical property of ecological variables observed across geographic space; its most common forms are patches and gradients. Spatial autocorrelation. which comes either from the physical forcing of environmental variables or from community processes, presents a problem for statistical testing because autocorrelated data violate the assumption of independence of most standard statistical procedures. The paper discusses first how autocorrelation in ecological variables can be described and measured. with emphasis on mapping techniques. Then. proper statistical testing in the presence of autocorrelation is briefly discussed. Finally. ways are presented of explicitly introducing spatial structures into ecological models. Two approaches are proposed: in the raw-data approach, the spatial structure takes the form of a polynomial of the x and .v geographic coordinates of the sampling stations; in the matrix approach. the spatial structure is introduced in the form of a geographic distance matrix among locations. These two approaches are compared in the concluding section. A table provides a list of computer programs available for spatial analysis.
3,491 citations