The 3/4 allometry holds for terrestria organisms, but for marine species it is more close to 2/3. An explanation and detailed discussion can be found in Platt, Trevor, and William Silvert. 1981. Ecology, physiology, allometry and dimensionality. J. Theor. Biol. 93:855-860.
Bill Silvert ----- Original Message ----- From: "Oskar Burger" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Tuesday, December 04, 2007 11:20 PM Subject: Are organisms really 4 dimensional objects? >A paper just made available on the American Naturalist website takes a >novel > and curious perspective on fundamental scaling relationships in ecology. > The > paper, by Ginzburg and Damuth, is titled "The space-lifetime hypothesis: > viewing organisms in 4 dimensions, literally." The authors argue that > organisms can literally be viewed as four dimensional objects, three > spatial > and one temporal. While many traits scale with body size, they > specifically > focus on the well-known finding that metabolic rate scales as the +3/4 > power > of body mass whereas lifespan goes as the +1/4 power. This makes the > product > of the two an isometric relationship (m3/4 x m1/4 = m1), such that a > doubling in an organism's size predicts a doubling in the energy it > metabolizes in a lifetime. While many researchers take this as a > consequence > of other scaling relationships it is a fundamental role in the 4D view...
