dorsal/arxiv
View SchemaRe-examination of the "3/4-law" of Metabolism
| Authors | Peter Sheridan Dodds, Daniel H. Rothman, Joshua S. Weitz |
|---|---|
| Categories | |
| ArXiv ID | physics/0007096 |
| URL | https://arxiv.org/abs/physics/0007096 |
| Journal | J. Theor. Biol., 209(1), pp 9-29 (2003) |
Abstract
We examine the scaling law $B \propto M^{\alpha}$ which connects organismal metabolic rate $B$ with organismal mass $M$, where $\alpha$ is commonly held to be 3/4. Since simple dimensional analysis suggests $\alpha=2/3$, we consider this to be a null hypothesis testable by empirical studies. We re-analyze data sets for mammals and birds compiled by Heusner, Bennett and Harvey, Bartels, Hemmingsen, Brody, and Kleiber, and find little evidence for rejecting $\alpha=2/3$ in favor of $\alpha=3/4$. For mammals, we find a possible breakdown in scaling for larger masses reflected in a systematic increase in $\alpha$. We also review theoretical justifications of $\alpha=3/4$ based on dimensional analysis, nutrient-supply networks, and four-dimensional biology. We find that present theories for $\alpha=3/4$ require assumptions that render them unconvincing for rejecting the null hypothesis that $\alpha=2/3$.
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"abstract": "We examine the scaling law $B \\propto M^{\\alpha}$ which connects organismal\nmetabolic rate $B$ with organismal mass $M$, where $\\alpha$ is commonly held to\nbe 3/4. Since simple dimensional analysis suggests $\\alpha=2/3$, we consider\nthis to be a null hypothesis testable by empirical studies. We re-analyze data\nsets for mammals and birds compiled by Heusner, Bennett and Harvey, Bartels,\nHemmingsen, Brody, and Kleiber, and find little evidence for rejecting\n$\\alpha=2/3$ in favor of $\\alpha=3/4$. For mammals, we find a possible\nbreakdown in scaling for larger masses reflected in a systematic increase in\n$\\alpha$. We also review theoretical justifications of $\\alpha=3/4$ based on\ndimensional analysis, nutrient-supply networks, and four-dimensional biology.\nWe find that present theories for $\\alpha=3/4$ require assumptions that render\nthem unconvincing for rejecting the null hypothesis that $\\alpha=2/3$.",
"arxiv_id": "physics/0007096",
"authors": [
"Peter Sheridan Dodds",
"Daniel H. Rothman",
"Joshua S. Weitz"
],
"categories": [
"physics.bio-ph",
"physics.data-an",
"q-bio.OT"
],
"journal_ref": "J. Theor. Biol., 209(1), pp 9-29 (2003)",
"title": "Re-examination of the \"3/4-law\" of Metabolism",
"url": "https://arxiv.org/abs/physics/0007096"
},
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