Here is a great little video (4:08) that discusses the rise of cities and how we now have 50% of the world’s population clustered in them. It takes us from HUNTING & GATHERING to IRRIGATION, DOMESTICATION OF ANIMALS, and SPECIALIZATION OF LABOR. It then discusses how humans need to prepare for further urban growth and take into consideration food production (VERTICAL GARDENING & ROOFTOP GARDENS), INDUSTRIAL POLLUTION, and RESOURCE CONSERVATION.

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