Crowd-sourcing the environment

October 21, 2015- If you are like me, you’re worried about the increasing amount of aggression displayed by people, both at home and abroad. School-yard and urban shootings, coupled with civil and jihadist wars, don’t make for calming nightly news.

So I’m going to go out on a limb with this blog, to suggest that these aggressive human behaviors derive from the stress of overcrowding in a world of rising human population.

Forty years ago, the population biologist, Charles Southwick, alerted us to the difference between high density and crowding. Some populations can persist at high densities if there is plenty of food, water and shelter. Others show the stress of crowding, even at lower densities, when these resources are in short supply and the news thereof is rapidly communicated through the population. And, Lord knows, with modern social media, the news anywhere is distributed everywhere within seconds.

In his earlier work, Southwick had shown direct correlations between the population density of house mice and aggressive behavior, increasing mortality of young, and deviant sexual behavior. Crowding leads increasing stress, changes in hormonal levels, hypertension, and declining health. As we crowd ourselves in cities, we are increasingly

disconnected from nature and the mental refreshment that nature offers.  As in other species, our increasing population numbers lead to mass migrations to new potential habitats.

So, when I look at the civil war in Syria that has caused massive human migrations of desperate people, I wonder just how much of their misery is derived from a decade of crop failures and droughts in that region, coupled with one of the highest rates of human population growth in the world. At least one study has linked drought in the Middle East to the impacts of global climate change, wrought by human emissions from fossil fuel combustion. The effluents of a rich industrialized society impact a region desperate for a better life.

Closer to home, when I look within my own country, I wonder just how much aggression amongst the youth is coupled with the perception of an increasing gulf between rich and poor and diminished expectations that the future can bring a better life. The aggression is enhanced among those who believe that resources are concentrated amongst those of

differential privilege. It is hard to know just what causes a disturbed young man to engage in the mass shooting of children and students, but my suspicion is that such individuals find it difficult to find a place in a crowded world of individuals who are each

aggressively seeking a share of a limited resource pie.

We will find it increasingly difficult to feed and shelter increasing numbers of humans across our planet, as we recognize that our population has exceeded the carrying capacity of the Earth. Efforts to stabilize our population are long overdue.


Kelley, C.P., S. Mohtadi, M.A. Cane, R. Seager and Y. Kushnir. 2015.

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McHarg, I. 1969. Design with Nature.  The Natural History Press,

Garden City, New York.

Miranda, M.L., D.A. Hastings, J.E. Aldy, and W.H. Schlesinger. 2011.

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Justice 4: 17-25.

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and animals.  Ohio Journal of Science 71: 65-72.