title: Experimental allometry: effect of size manipulation on metabolic rate of colonial ascidians.
abstract: The allometric scaling of metabolic rate of organisms, the three-quarters power rule, has led to a questioning of the basis for the relation. We attacked this problem experimentally for the first time by employing the modular organism, the ascidian that forms a single layered flat colony, as a model system. The metabolic rate and colony size followed the three-quarters power relation, which held even after the colony size was experimentally manipulated. Our results established that the three-quarters power relation is a real continuous function, not an imaginary statistical regression. The fact that all the hypotheses failed to explain why the two-dimensional organism adhered to the three-quarters power relation led us to propose a new hypothesis, in which the allometric relation derives from the self-organized criticality based on local interaction between modulus-comprising organisms.
authors.affiliation: Graduate Division of Life Science, Graduate School of Humanities and Sciences, Ochanomizu University, Ohtsuka, Bunkyo, Tokyo 112-8610, Japan. nakaya@cc.ocha.ac.jp
authors.forename: Fumio
authors.initials: F
authors.lastname: Nakaya
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Saito
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Motokawa
mesh_terms: D000818:Animals; D001699:Biometry; D001835:Body Weight; D004734:Energy Metabolism / Q000502:physiology*; D007564:Japan; D012044:Regression Analysis; D014561:Urochordata / Q000033:anatomy & histology / Q000502:physiology*