Effects of environmental factors and body size on rates of oxygen consumption in Archaeomysis grebnitzkii and Neomysis awatschensis (Crustacea: Mysidae)

1. The oxygen consumption of the echiuroid Bonellia viridis has been investigated by means of a continuous-flow polarographic respirometer. 2. The general rate of oxygen consumption per unit dry weight is similar to that characteristic of polychaetes, and declines exponentially with increasing body size. 3. The rate of oxygen consumption rises in the light and falls again if darkness is restored. 4. The oxygen consumption of the isolated proboscis plus that of the isolated body region corresponds closely to that of the entire animal. 5. The oxygen consumption per unit dry weight of the proboscis is considerably higher than that of the body region. 6. The oxygen consumption of an isolated body region increases in the presence of light, but that of an isolated proboscis does not. 7. These findings are discussed in relation to the biology of the animal, observed muscular activity, and the occurrence of the pigment bonellin.

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The Relation of Oxygen Consumption to Body Size and to Temperature in the Larvae of Chironomus Riparius Meigen

Journal of Experimental Biology ◽

10.1242/jeb.35.2.383 ◽

1958 ◽

Vol 35 (2) ◽

pp. 383-395

Author(s):

R. W. EDWARDS

Keyword(s):

Oxygen Consumption ◽

Body Size ◽

Dry Matter ◽

Larval Instar ◽

Weight Ratio ◽

Dry Weight ◽

Chironomus Riparius ◽

Consumption Rates ◽

Rate Of Oxygen Consumption ◽

Wet Weight

1. The oxygen consumption rates of 3rd- and 4th-instar larvae of Chironomus riparius have been measured at 10 and 20° C. using a constant-volume respirometer. 2. The oxygen consumption is approximately proportional to the 0.7 power of the dry weight: it is not proportional to the estimated surface area. 3. This relationship between oxygen consumption and dry weight is the same at 10 and at 20° C.. 4. The rate of oxygen consumption at 20° C. is greater than at 10° C. by a factor of 2.6. 5. During growth the percentage of dry matter of 4th-instar larvae increases from 10 to 16 and the specific gravity from 1.030 to 1.043. 6. The change in the dry weight/wet weight ratio during the 4 larval instar supports the theory of heterauxesis. 7. At 20° C., ‘summer’ larvae respire faster than ‘winter’ larvae.

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Effects of hypoxia and body size on the oxygen consumption of the bivalve Arctica islandica (L.)

Journal of Experimental Marine Biology and Ecology ◽

10.1016/0022-0981(75)90046-5 ◽

1975 ◽

Vol 19 (2) ◽

pp. 187-196 ◽

Cited By ~ 59

Author(s):

A.C. Taylor ◽

A.R. Brand

Keyword(s):

Oxygen Consumption ◽

Body Size ◽

Arctica Islandica

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Biology, not environment, drives major patterns in maximum tetrapod body size through time

Biology Letters ◽

10.1098/rsbl.2012.0060 ◽

2012 ◽

Vol 8 (4) ◽

pp. 674-677 ◽

Cited By ~ 27

Author(s):

Roland B. Sookias ◽

Roger B. J. Benson ◽

Richard J. Butler

Keyword(s):

Body Size ◽

Environmental Factors ◽

Abiotic Factors ◽

Logistic Models ◽

Growth Curves ◽

Maximum Size ◽

Generalized Least Squares ◽

Least Squares Regression ◽

Geological Time ◽

Cenozoic Mammals

Abiotic and biological factors have been hypothesized as controlling maximum body size of tetrapods and other animals through geological time. We analyse the effects of three abiotic factors—oxygen, temperature and land area—on maximum size of Permian–Jurassic archosauromorphs and therapsids, and Cenozoic mammals, using time series generalized least-squares regression models. We also examine maximum size growth curves for the Permian–Jurassic data by comparing fits of Gompertz and logistic models. When serial correlation is removed, we find no robust correlations, indicating that these environmental factors did not consistently control tetrapod maximum size. Gompertz models—i.e. exponentially decreasing rate of size increase at larger sizes—fit maximum size curves far better than logistic models. This suggests that biological limits such as reduced fecundity and niche space availability become increasingly limiting as larger sizes are reached. Environmental factors analysed may still have imposed an upper limit on tetrapod body size, but any environmentally imposed limit did not vary substantially during the intervals examined despite variation in these environmental factors.

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Cope's Rule and Romer's theory: patterns of diversity and gigantism in eurypterids and Palaeozoic vertebrates

Biology Letters ◽

10.1098/rsbl.2009.0700 ◽

2009 ◽

Vol 6 (2) ◽

pp. 265-269 ◽

Cited By ~ 45

Author(s):

James C. Lamsdell ◽

Simon J. Braddy

Keyword(s):

Body Size ◽

Environmental Factors ◽

Feeding Strategy ◽

Large Body ◽

Large Body Size ◽

Causal Mechanisms ◽

Family Level ◽

Cope’S Rule ◽

Abiotic Environmental Factors

Gigantism is widespread among Palaeozoic arthropods, yet causal mechanisms, particularly the role of (abiotic) environmental factors versus (biotic) competition, remain unknown. The eurypterids (Arthropoda: Chelicerata) include the largest arthropods; gigantic predatory pterygotids (Eurypterina) during the Siluro-Devonian and bizarre sweep-feeding hibbertopterids (Stylonurina) from the Carboniferous to end-Permian. Analysis of family-level originations and extinctions among eurypterids and Palaeozoic vertebrates show that the diversity of Eurypterina waned during the Devonian, while the Placodermi radiated, yet Stylonurina remained relatively unaffected; adopting a sweep-feeding strategy they maintained their large body size by avoiding competition, and persisted throughout the Late Palaeozoic while the predatory nektonic Eurypterina (including the giant pterygotids) declined during the Devonian, possibly out-competed by other predators including jawed vertebrates.

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