RT Journal Article SR Electronic T1 A General Model for the Origin of Allometric Scaling Laws in Biology JF Science JO Science FD American Association for the Advancement of Science SP 122 OP 126 DO 10.1126/science.276.5309.122 VO 276 IS 5309 A1 West, Geoffrey B. A1 Brown, James H. A1 Enquist, Brian J. YR 1997 UL http://science.sciencemag.org/content/276/5309/122.abstract AB Allometric scaling relations, including the 3/4 power law for metabolic rates, are characteristic of all organisms and are here derived from a general model that describes how essential materials are transported through space-filling fractal networks of branching tubes. The model assumes that the energy dissipated is minimized and that the terminal tubes do not vary with body size. It provides a complete analysis of scaling relations for mammalian circulatory systems that are in agreement with data. More generally, the model predicts structural and functional properties of vertebrate cardiovascular and respiratory systems, plant vascular systems, insect tracheal tubes, and other distribution networks.