A Tangent On: Lawns and Human Nature
There’s an interesting hypothesis in the psychology of human aesthetic preference which holds that we can explain the modern prevalence of lawns and other open, grassland-like landscaping features, at least in part, by looking to our species’ evolutionary past. The idea is that because we likely evolved on the savannahs of east Africa, we have a deeply ingrained preference for open plains over other habitat types, such as dry deserts and dark, crowded forests. Thus, we continue to model our modern settlements after our evolutionary cradle by maintaining thousands of acres of open parkland.
As far as I can tell, this idea was originally proposed by zoologist and educator John H. Falk in a 1977 article on lawns for Smithsonian magazine, in which he suggested that there may be a significant evolutionary basis for our landscape preferences. A few years later, in 1982, Falk published a paper with psychologist John D. Balling which sought to test this hypothesis. For their study, Balling and Falk showed pictures of various habitats to 548 people, mostly from the Midatlantic states, and ranging in age from third graders to senior citizens. They then asked each participant to rate the places in the pictures based on whether they would want to live there and on whether they would want to visit. They found that younger children interviewed for the study showed a significant preference for savannah-like habitats (including actual savannahs, as well as lawns and parks) while older participants preferred habitats that they were personally familiar with (mostly temperate forests in this case) just as much as savannahs.
The authors suggest that the significant preference for savannah-like habitats among pre-adolescent children could reflect an innate, genetically determined preference for open habitats which is then modified by life experience as they get older. This modification does not necessarily eliminate that initial attraction to open habitats — most of the adults in the study also liked the savannah photos — but may result in another habitat supplementing or even subsuming it as the person’s preference. A group of professional foresters who mostly worked in conifer forests, for example, pretty much all rated pictures of conifer forests the highest.
At the same time, the authors acknowledge that both the adult’s more varied preferences and the children’s specific preference for savannah-like habitats could also be explained by invoking familiarity. After all, the reason they were interested in performing this study in the first place had to do with the apparent ubiquity of savannah-like landscaping features. It seems very likely that a lot of these kids would have grown up in cities and suburbs where lawns and parks are fairly common and that they might be more personally familiar with them than the other habitats that they were asked to rate. It's also hard to rule out softer, cultural factors, such as the portrayal of forests as dark and scary in certain children's stories and other media.
In the decades since this study was published, a modest literature has continued to grow up around what has become known as the “Savannah Hypothesis.” For their part, Falk and Balling became more confident in their evolutionary interpretation after attempting to replicate their 1982 study in Nigeria. In a 2010 paper, they reported that students from two rural secondary schools in the River State appeared to share the American children’s preference for savannah-like habitats despite not having much of any personal experience with them. They interpreted these results as further supporting the idea of a universal, base preference for open habitats rooted in genetics over culture. Personally, I don’t find this interpretation very convincing, however, given that they did not attempt to replicate the 1982 results with a similar cohort of Nigeran adults and that these kids were probably familiar with and had favorable opinions of other open habitats, such as agricultural and soccer fields. What’s more, other studies appear to have failed to replicate significant parts of these findings back in the U.S. Whereas Falk and Balling found that adolescents and adults had the same level of preference for savannah-like habitats as they did for more familiar forest habitats, Han (2007) found that grassland habitats were among the least favored in a sample of 274 college students. Meanwhile, Lyons (1983) found that his sample of third graders preferred local temperate forests over dry east African savannahs.*
The idea that humans might have an innate, genetic preference for certain landscapes is by no means an implausible one — humans are animals that are subject to evolution and there is some evidence of a genetic basis for habitat preference in certain common model organism (Jaenike and Holt 1991) — but based on the admittedly modest number of papers that I read for this essay, it doesn’t seem to me that there is nearly enough evidence to say for certain that we prefer savannahs. I do think that it is interesting, however, that even in the models being proposed which include such a preference, it is never presented as the only factor impacting any individual person's landscape preferences — lived experience, in study after study, seemed to play a much clearer, much more significant part. Familiarity seems to be especially highly correlated with landscape preference, but so are factors like career and social group. The foresters discussed above are an obvious example of the former, while a group of older, urban college students also interview by Falk and Balling in Nigeria are perhaps, in their overall rejection of the local rainforest habitats, an example of the latter. Answers to questions about landscape preference may also be impacted by more immediate concerns, such as local weather — Han’s college students were all recruited in spring from hot and humid Texas A&M University, which may explain their preference for alpine tundra and coniferous forest habitats.
As somebody who likes to write about human-created landscapes in ecological and evolutionary terms, I think that the existence of this kind of complexity is really important to keep in mind when discussing human beings as a part of the natural world. There can sometimes be a tendency, when we talk about what is “natural,” to assume a kind of simple necessity or inevitability is involved. Even at its weakest, the claim that an event is “natural” often seems to imply that it will proceed as observed so long as there is no outside interference; at its strongest, it means that it will be that particular way no matter what happens. Probably the most well-known example of this stronger sense of nature’s “necessity” can be found in what we call “Laws of Nature,” which unlike human laws, cannot be meaningfully “broken.” Nothing compels an object to follow Newton’s First Law of Motion, but it is something that all objects seem to do, such that if we were to discover an object which didn’t, we would simply stop referring to the First Law of Motion as a Law.
As we move out of physics and chemistry, and into sciences like biology, psychology, and sociology, which study much more complex systems, things seem to become more contingent and there are fewer and fewer of these simple, universal Laws (Mayr 1988; Godfrey-Smith 2021). Nonetheless, the search for such rules is a tempting one — the concept of a unified human nature in which we can root morality, politics, economics, and social policy would certainly make life a lot easier. Certainly, there are some features which all people largely share (we all need to eat, and I would wager that some form of social interaction is important for the happiness of most, if not all of us), but these tend to be rather vague, and the details are rarely simple or universal. Often, it seems more likely that we as a species will have a tendency towards trait x in environment y or z, which can be affected by the interactions between traits q, r , or s and expressed in form a, b, c, d…or just not at all.
Seeing ourselves in this way has important practical implications, as does assuming an overly simplistic outlook on human nature. I’ve had conversations before with people about environmental problems in which we largely agree on what has to be done in order to solve them, but disagree on their practicality. Sometimes, the person’s pessimism is based on some statistic about the availability of resources or the efficacy of clean energy tech, but other times it will be routed more in their view of what people are like. If the person believes that greed, while not an inevitable, universal human trait, is a tendency that is common enough that any given human is more likely to act greedily than not, they will obviously see the world and respond to it very differently from a person who thinks that humans tend more often to be generous. In the case of environmental policy specifically, I have heard people reject the possibility of saving the planet on the grounds that human beings are just too greedy to restrain themselves.
I think that it’s easy to imagine a case where a person hears an overly simplified version of the Savannah Hypothesis and comes to a similar conclusion — that addressing the various environmental problems associated with lawns and other kinds of open landscaping features is impossible, when the actual research seems to show the opposite. A preference for familiarity, while no insignificant obstacle to change, is absolutely possible to overcome simply by introducing people to new and different landscapes. Even if we eventually learn that humans do have a genetic preference for open habitats and that it has a more significant impact on our landscaping preferences than I, at least, would tend to suspect, this still doesn’t mean that lawns are inevitable. As we’ve previously discussed, lawns are just one kind of open habitat and their unique socioecological features have clearly been influenced by identifiable and contingent historical trends, including Feudalism, Pastoralism, European Imperialism, Chemical Industrialism, and good old fashion American Consumerism (Jenkins 1994; Ignatieva and Ahrne 2009; Ignatieva and Ahrne 2013). The fact that more recent trends, such as Environmentalism, have led to the development of alternative, open landscaping options that some people have adopted should act as a warning against assuming the inevitability of an unsatisfactory status quo. (And so should anybody you know who isn’t a greedy jerk).
The complexity of human nature means that we are often capable of change, but it also means that we make mistakes. Whenever I attempt to analyze human behavior or human-created habitats from an ecological perspective, I always make an effort not to imply that any aspects of our ecological interactions are inevitable unless I have very good evidence to back it up. I suspect, however, that I will or already have sometimes failed to meet this goal — some degree of certainty about the world is, after all, part of the appeal of any science and I am by no means immune to it. So, if there is one thing I would hope that you take away from this little essay, it would be an attitude of skepticism, not towards the possibly of reasonable certainty, but towards overly simplistic claims about outright necessity in complex systems, such as human societies. It is a worthwhile goal, I think, to try and break apart the artificial boundaries that we have put up between nature and culture which deny their interactions with each other, but we have to be careful not to do so in such a way that contemporary cultural institutions are subsumed into a picture of nature in which they are incorrectly assumed to be inevitable.
We can’t allow pessimism to infect our sense of possibility so easily — sometimes, people tear up their lawns and plant pollinator gardens.
*Lyons showed his participants photographs of dry savannah habitats, as well as one photograph of a wetter, lusher savannah. This photograph was actually widely favored but was removed from the study because there were not enough similar replicates. Since Balling and Falk used a mix of photographs of savannahs, lawns, and parks in both of their studies, it's hard to make a direct comparison between the two. Assuming that landscape preference does have a universal genetic component, however, Lyons’ results do at least suggest the possibility that specific landscape elements or features, such as aridity, may play an equal or more important part in determining preference than the biome (Hartmann and Apaolaza-Ibáñez 2010). He also found that college students from the American southwest rated dryer desert and grassland habitats more highly, however, reminding us that life experience is still a major factor here.
Sources:
Balling, J. D., & Falk, J. H. (1982). Development of visual preference for natural environments. Environment and behavior, 14(1), 5–28.
Falk, J. H., & Balling, J. D. (2010). Evolutionary influence on human landscape preference. Environment and behavior, 42(4), 479–493.
Godfrey-Smith, P. (2021). Theory and reality: An introduction to the philosophy of science. Second Edition. University of Chicago Press.
Han, K. T. (2007). Responses to six major terrestrial biomes in terms of scenic beauty, preference, and restorativeness. Environment and Behavior, 39(4), 529–556.
Hartmann, P., & Apaolaza-Ibáñez, V. (2010). Beyond savanna: An evolutionary and environmental psychology approach to behavioral effects of nature scenery in green advertising. Journal of Environmental Psychology, 30(1), 119–128.
Ignatieva, M., & Ahrné, K. (2013). Biodiverse green infrastructure for the 21st century: from “green desert” of lawns to biophilic cities. Journal of Architecture and Urbanism, 37(1), 1–9.
Ignatieva, M., & Stewart, G. H. (2009). Homogeneity of urban biotopes and similarity of landscape design language in former colonial cities. Cambridge University Press.
Jaenike, J., & Holt, R. D. (1991). Genetic variation for habitat preference: evidence and explanations. The American Naturalist, 137, S67-S90.
Jenkins, V. S. (1994). The lawn: A history of an American obsession. Smithsonian Institution.
Joye, Y., & Van den Berg, A. (2011). Is love for green in our genes? A critical analysis of evolutionary assumptions in restorative environments research. Urban Forestry & Urban Greening, 10(4), 261–268.
Lyons, E. (1983). Demographic correlates of landscape preference. Environment and behavior, 15(4), 487–511.
Mayr, E. (1988). Toward a new philosophy of biology: Observations of an evolutionist. Harvard University Press.
Photo Credits:
(1) “New Haven Green Looking NE” by Iracaz (CC BY-SA 3.0)
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