It's probably not interesting to most people, but I find it fascinating: a scientist has decided that cities are different from anything else in the biological sphere (i.e. cities are, after all, collective organisms), because they experience "superlinear growth." Which is to say, cities grow faster as they grow bigger – whereas growth in every other biological system slows down as it gets bigger. What are the implications of this? Is this like comparing apples and oranges? Read a NYT article here, or another article by Stewart Brand here.