Well, you can scale for mass, just not linearly. Metabolism scales with mass^(3/4). Interestingly, so do the number of cars in a city with a city's population

Well, you can scale for mass, just not linearly. Metabolism scales with mass^(3/4). Interestingly, so do the number of cars in a city with a city's population size- this is a fun essay on the subject: http://opinionator.blogs.nytimes.com/2009/05/19/math-and-the-city/ http://opinionator.blogs.nytimes.com/2009/05/19/math-and-the...