The Ecological Implications of Body Size bookline Question: Associations of body size and of body temperature with fitness have. fitness metric for a particular ecological context population and environment. Size impacts nearly all aspects of an organism's morphology, physiology,. EVOLUTION OF BODY SIZE: CONSEQUENCES OF AN.-Biology ecologie.snv.jussieu.fr/mmassot/ ecologie.snv.jussieu.fr/cgpa/. Ecological and evolutionary implications of body size illustration with a study on the Ecological and evolutionary consequences of size-selective. The Ecological Implications of Body Size by Peters, R.h. at Pemberley Books. Scaling and the Ecological Implications of Body Size The Ecological Implications of Body Size, szerz?: Peters, Robert H., Kategória: Ecology, Ár: 23 451 Ft. More of the intraclass evolution of animals has been linked to body size than to any other characteristic. Size, temperature, and fitness: three rules-University of Washington many aspects of the ecology of a species, body size provides a useful surrogate. can explore the implications of body size on the structure and functioning of Ecological Implications Body Size Lecture Slides-Scaling and the. The ecological implications of body size / Robert Henry Peters on ResearchGate, the professional network for scientists. Exploring the ecological implications of insect body size AbeBooks.com: The Ecological Implications of Body Size Cambridge Studies in Ecology 9780521288866 by Peters, Robert Henry and a great selection of Behavioral ecological implications of early hominid body size 30 Mar 2007. and density is the inverse of the relationship between body size and 1

Patterns in life history phenomena may be demonstrated by examining wide ranges of body weight. Positive relationships exist between adult body size and the clutch size of poikilotherms, litter weight, neonate weight life span, maturation time and, for homeotherms at least, brood or gestation time. The complex of these factors reduces r in larger animals or, in more physiological terms, r is set by individual growth rate. Comparison of neonatal production with ingestion and assimilation suggests that larger mammals put proportionately less effort into reproduction. Declining parental investment and longer development times would result if neonatal weight is scaled allometrically to adult weight and neonatal growth rate to neonatal weight. Body size relations represent general ecological theries and therefore hold considerable promise in the development of predictive ecology.

A comparative analysis of planktonic metabolism in 20 southern Quebec lakes was carried out to test the hypothesis that planktonic P: R ratios reflect gradients of both nutrient enrichment and dissolved organic carbon (DOC). Mean epilimnetic phytoplankton photosynthesis ranged from 8 to 377 mg C m-3 d-l, and the amount of C respired by the plankton in excess of phytoplankton photosynthesis ranged from 30 to 86 mg C m-3 d-l. Plankton community respiration was 2-8 times greater than phytoplankton photosynthesis in all oligotrophic and mesotrophic lakes during the growing season, and this imbalance narrowed toward the more productive lakes. P: R ratios were positively related to chlorophyll and total P concentration, and inversely related to water color and DOC concentration. The strong influence of DOC on planktonic P: R ratios was almost exclusively due to its depressing effect on phytoplankton photosynthesis; DOC had no statistical effect on respiration. The calculated DOC loading for these lakes suggests that organic C loss through epilimnetic respiration in excess of phytoplankton photosynthesis is comparable to the estimated DOC loss within the lakes and that summer plankton metabolism could be supported by external DOC inputs in most lakes. The highly significant intercept of the respiration to production relationship, 27 mg C m-3 d-l, may indicate the baseline metabolism supported by external sources of C that occurs in these temperate lakes. Estimates of respiratory CO2 production from the pelagial of these lakes range from 11 to 60 mmol CO, m-2 d-l, depending on lake trophy and DOC concentration. These estimates suggest that the planktonic metabolism of allochthonous DOC probably constitutes a major source of CO, in lakes.

Multiple regression analysis of published zooplankton filtering and feeding rates yielded separate regression equations for cladocerans, marine Calanoid copepods, and all zooplankton. Ingestion rate was found to increase significantly with animal size, food concentration, and temperature. Filtering rate also increased with animal size and temperature, but declined as food concentration increased. The analysis suggests a difference in particle size preference between cladocerans and copepods. Experimental conditions such as crowding and duration also significantly affected filtering and feeding rates. The regression models allow examination of differences and similarities among zooplankton taxa, functional response, particle size selection, energy allocation, and threshold food concentration. The statistical models describe suspension feeding more precisely than either average literature values or verbal descriptions of trend. The results also suggest possible mechanisms of feeding limitation and provide a heuristic framework for the design of experimental analyses of zooplankton feeding in marine and freshwater systems.

Although it is a commonplace that small animals are more abundant than large ones, few attempts have been made to quantify this and none for non-mammalian species. This study uses estimates of animal density and body mass culled from 12 journals published between 1961 and 1978 to test and extend Damuth's relationship between population density and body size of herbivorous mammals. In general, his analysis is supported, for density usually declines roughly as W and poikilotherms maintain higher densities than homeotherms. However the residual variation is higher than Damuth's regressions might suggest and significant differences exist among animal groups. In particular, birds maintain much lower, and aquatic invertebrates much higher abundances than a general curve for all species would suggest. Carnivores are significantly rarer than herbivores. These relationships may be used to compare the average relative contributions of species of different size to community structure and function. Such relations also provide a necessary basis both for more complete empirical analyses of the determinants of animal abundance and for the construction of more realistic conceptual models in theoretical ecology.

Plankton communities in oligotrophic waters are characteristically dominated by the biomass of heterotrophs, including bacteria, micro‐, and macrozooplankton. It has been generally assumed that these inverted biomass pyramids are the direct result of high specific production rates of phytoplankton and a tight coupling between producers and consumers. There are, however, at least two alternative hypotheses: (1) heterotrophic biomass turnover is much slower in oligotrophic than eutrophic systems; and (2) oligotrophic planktonic communities are significantly subsidized by allochthonous organic matter. In this study we assessed these hypotheses by establishing the relationship between plankton biomass structure (partition between auto‐ and heterotrophs), plankton function (plankton primary production and respiration) and whole‐lake gas (O2 and CO2) fluxes in 20 temperate lakes that span a large range in primary production. We show that the balance of phytoplankton production and community respiration (P/R ratio) is always below unity in unproductive lakes where heterotrophic biomass (H) is high relative to autotrophic biomass (A), suggesting that these planktonic food webs function as heterotrophic systems and must be subsidized by allochthonous organic matter. Further, rates of phytoplankton specific production are not highest in communities characterized by dominance of heterotrophic biomass. All except the most productive lakes were supersaturated in CO2 and undersaturated in O2. Our results support the hypothesis that excess CO2 in lakes originates from the breakdown of terrestrial organic carbon by planktonic organisms. A simple model in which both allochthonous organic matter and phytoplankton production support the metabolism of heterotrophs reproduced the patterns and magnitudes of metabolism, P/R ratio, biomass turnover time, and whole‐system gas flux among lakes. These patterns of metabolism and structure suggest that inverted biomass pyramids in temperate lakes, and perhaps in other aquatic systems, reflect the heterotrophic nature of these plankton communities rather than turnover rates of autotrophs or heterotrophs.

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Lakes with anoxic hypolimnia (anoxic lakes) have significantly lower values for phosphorus retention than do lakes with aerobic hypolimnia (oxic lakes). This difference may reflect an increased internal phosphorus load from the anoxic hypolimnia.Two models are given to predict internal phosphorus load (L;,,) in such lakes. The first predicts internal load as the difference between the observed phosphorus retention in anoxic lakes and that predicted (Rpred) by a formula that adequately describes phosphorus retention in oxic lakes. The second predicts internal load as the product of an average rate of phosphorus release from anoxic sediments, the surface area of the anoxic sediment, and the period of anoxia. Predictions of the first model compare favorably with 17 observed values of internal load; further data are required to test the second model. These models suggest that mean phosphorus concentration (TP) in anoxic lakes can be predicted in two ways. One can use whole-lake phosphorus budget models which implicilly incorporate internal phosphorus load, because they include a measurement of phosphorus retention. Alternatively, a term to account for the internal load can be added to current models based on external load (L,,,) and predicted retention (I&J, where qs is areal water load:' A contribution to Formula Rcfcrcncc R, = IO/(10 -t q,) Vollenweidcr 1975 R, = 13.2J13.2 + qJ Dillon and Kirchner 1975 R3 = 16/(16 + qJ Chapra 1975 R, = 24/(30 + q,J Ostrofsky 1978a R, = 0.426 exp(-0.271q.J Kirchner and t-O.574 exp(-0.00949q.J Dillon 1975 R, = l/(1 -I-l/fi) Larsen and Mercier 1976