An Ecology of Houses

Guest blog post by Kevin Burke.

When I think of nature, I conjure up an image of a landscape unadulterated by human presence. In my mind, I am standing in an open grassland with a pristine forest in the not-too-distant background and I hear birds chirping and mosquitoes buzzing in my ear. Others may picture thick tropical foliage where bright flowers pop out against a background of varying greens, set to a soundtrack of running water that snakes through seemingly uncharted territory. The exact image probably varies from person to person, but I think it's a safe bet that humans are conspicuously absent from these landscapes, or, at most, they are visualized as a few hunter-gathers roaming a forest in search of food. The image doesn't include people in either their make-shift encampment or permanent residence the same way we might picture a bird in its nest. Nature, it is thought, is not our houses, nor does it exist in our backyards or along the banks of a polluted or drying-up river.

Despite the fact that we are currently facing enormous environmental problems, we have inherited an image of nature invented by 19^th century American romantics, who were writing not long after Native Americans were forcefully removed from the landscape and put onto reservations. This is one way in which nature has been constructed - in our imagination. However, nature is (and always has been everywhere humans have ever lived) at least partially constructed by human activity in a very real sense, and this process has (and has had) implications for human evolution by altering the process of natural selection.

This process, which is called ecological niche construction, views an organism as embedded in an environment that the organism itself is capable of altering[1]. These modifications then change selection pressures on that organism, and they change selection pressures on other evolving organisms too. Since the 1980s, the primary cause of the changing landscape in the United States has been suburban sprawl - i.e. the construction of strip malls, roads, and, particularly housing along the outskirts of cities in a seemingly haphazard and unplanned fashion[2]. Selection in this environment has been for increasing profits and economic growth as opposed to a strict biological interpretation of fitness. In many ways, it is Darwinian, but is it natural (in terms of ‘Natural Selection')?

Whenever construction of this sort is mentioned, the word economics is usually mentioned in the same breath. This is probably more so now than ever, especially with the recent downturn in the economy that resulted from the collapse of the housing market, whose boom and subsequent bust was caused by speculative trading on Wall Street. Ecology usually isn't mentioned in this regard, and I doubt the trading floors of Wall Street enter into the image of a fictitious nature for anyone. However, it is interesting to note that the words economy and ecology share the same word part, eco-, which actually comes from the ancient Greek word oikos, meaning house.

Starting in the 1950s, major US industrial cities saw a decrease in population size as middle class (primarily white) Americans fled the cities for the suburbs. While some cities (such as New York) maintained their population as the US economy shifted from industrial capitalism to finance capitalism, many cities continued to lose residents, who moved into newly constructed houses outside of the city. Land that was previously used for farming or was covered with forest has increasingly been converted to residential neighborhoods, which has a major impact on the local and global environment.

Globally, sprawl has contributed to global warming due to increased emissions from cars, which are the primary mode of transportation outside of urban areas, and increases in energy consumption for the heating and cooling of spacious suburban houses[3]. This consumption is also a primary driver behind resource extraction including oil drilling, hydraulic fracturing (a.k.a. ‘fracking') for natural gas, and coal mining - all of which have major implications for the local environments from which they are taken[4].

Probably the most notable consequence of resource extraction for local environments is water contamination. Unfortunately, the number of cases is steadily increasing, but one only needs to recall the BP Deepwater Horizon disaster from 2010 to get a feel for the scale of environmental contamination we are talking about. Besides indirectly causing contamination, sprawl is directly linked to water depletion. For example, water supply is not only becoming a concern for cities in deserts such as Las Vegas, which saw major development throughout the 90s and early 2000s, but also other metropolitan areas that are experiencing major population growth. As a case in point, the Raleigh-Durham-Chapel Hill area in North Carolina experienced a drought in 2007-08 that was exacerbated by the increased pressure on water supplies due to residential development[5].

In light of the environmental problems we are facing, it is necessary that we rethink what natural selection is. Instead of being analogous to Adam Smith's invisible hand, we must realize that there are very real hands at work that construct the environment and alter the course of evolution for humans and non-humans alike. This construction, however, should not only be for short-term economic growth. The romantic image of nature that we have inherited sees nature as some entity detached from humans. This view is (and probably always has been) a bit anachronistic, only really existing in the time before modern Homo sapiens evolved and dispersed around the globe. A more contemporary version of nature makes humans an integral part of it. I don't mean to suggest that we should completely forget romanticism and reduce nature's beauty to simple (and selfish) utilitarian calculations. I am, admittedly, a bit of a romantic myself who loves a good ramble in the woods every now and again. It is simply a reminder that part of what is so beautiful about a clean river and expansive forests is that we depend on them. We simultaneously construct and are constructed by the environment; we envelop and are enveloped by it. If the environment we build for ourselves is only for the short term, then that's how long it'll last.

[1] Laland KN, Boogert NJ (2010). Niche Construction, Co-evolution and Biodiversity. Ecological Economics 69: 731-736.

[2] Wade AA, Theobald DM (2010). Residential Development Encroachment on US Protected Areas. Conservation Biology 24: 151-61.

[3] Gonzalez G.A. (2005). Urban Sprawl, Global Warming and the Limits of Ecological Modernization. Environmental Politics 14: 344-362.

[4] Finer M, Jenkins CN, Pimm SL, Keane B, Ross C (2008) Oil and Gas Projects in the Western Amazon: Threats to Wilderness, Biodiversity, and Indigenous Peoples. PLoS ONE 3(8): e2932

Palmer MA, Bernhardt ES, Schlesinger WH, Eshleman KN, Foufoula-Georgiou E, Hendryx MS, Lemly AD, Likens GE, Loucks OL, Power ME, White PS, Wilcock PR (2010). Mountaintop Mining Consequences. Science 327: 148-49.

[5] Rohe, W.M. (2011). The Research Triangle. Philadelphia: University of Pennsylvania Press.