Scaling Laws In Biology And Other Complex Systems

Google Tech talks
August 1, 2007


Life is very likely the most complex phenomenon in the Universe manifesting an extraordinary diversity of form and function over an enormous range. Yet, many of its most fundamental and complex attributes scale with size in a surprisingly simple fashion. For example, metabolic rate (the power required to sustain the system) scales as approximately the 3/4-power of mass over 27 orders of magnitude from molecular levels up to the largest multicellular organisms. Similarly, time-scales, such as lifespans and growth-rates, increase with exponents which are typically simple powers of 1/4. It will be shown how these universal quarter-power scaling laws follow…