A final word Population can be a controversial subject. Feelings about family size, lifestyle and immigration run deep, coming from individual and collective histories, religious beliefs and cultural attitudes. Environmentalists, for example, are not concerned with the ethnic origin of our population, but about population numbers and levels of consumption. For others, though, these issues have different levels of meaning. Whatever actions we choose to take are a means to the end of living sustainably, they are not an end in themselves.
Humans congregate in groups.
When our numbers were small and our groups migratory our environmental impact was small, and ecosystems had time to recover as populations moved around. When we settled in villages surrounded by farms, our impact increased. Although populations grew, farming and industry was local, using human and animal labour, and much land remained in a natural condition. Now that we live in cities, with machine-driven agriculture and industry, and fossil fuels to supply our consumables and remove our waste, our impact is enormous. We're interested in your viewpoint.