Manuel De Landa, A Thousand Years of Nonlinear History, New York: Zone Books, 1997.
In A Thousand Years of Non-Linear History, De Landa describes the city as a human exoskeleton. About 8,000 years ago houses, walls and monuments supported new densities of entangled human bodies. These mineralised-fortifications conducted flows of flesh, energy and food in and out of a town’s walls. Invisible bacteria and new sources of food and energy shaped the (political) form of the urban environment: “From different perspectives, cities and towns may themselves be considered ecosystems, at least to the extent that biomass circulates through them to feed their inhabitants”.
Dowload a file of quotes here [pdf] .