It is well known that spending time in nature has benefits in terms of mental and physical health, and yet we are not all drawn toward the natural world with the same passion. In trying to understand individual differences in the way we experience nature, environmental factors (such as parental attitudes and access to natural areas) have received the most attention. The potential role of genes in this variation between individuals has been overlooked.
For the first time, scientists have now investigated the contribution of genes and heritability to various aspects of our individual appreciation of nature. The research was focused on data from a large-scale study of UK twins and was led by Chia-Chen Chang at the National University of Singapore.
Researchers surveyed 1,153 pairs of twins listed on the TwinsUK registry. Some of the twins were monozygotic (identical), indicating that they would share almost 100 percent of their genes, while others were dizygotic twins (non-identical) who would share about 50 percent of their genes. The average age of the twins in the study was 60 years, and the participants ranged from 19 – 89 years of age.
The twins were asked to rate their familiarity with and desire to be in nature (termed nature orientation), as well as the frequency with which they visit natural spaces such as public parks and private gardens (termed nature opportunity). Both nature orientation and opportunity have been hypothesized to have a heritable component, but this has never been tested. In addition, the relative contributions of genetic and environmental factors in explaining individual variation in nature experience remains unexplored.
The results of the study, published today in the open access journal PLoS Biology, found that identical twins were more similar to each other than non-identical twins in their orientation towards nature and in their nature experience – how often they visited public open space, and their frequency and duration of visits to gardens.
Heritability ranged from 46 percent for nature orientation to 34 percent for frequency of garden visits, suggesting a moderate influence of genetics over how people experience nature.
However, environmental factors explained more than half of the differences between individuals. For example, people living in urban environments tended to have less frequent nature experiences due, probably, to their more limited access or greater travel times to gardens and public open spaces. This result highlights the importance of availability in shaping nature-seeking behaviors.
Heritability also declined with age, suggesting that genetics may become less influential as people age and experience a unique set of environmental conditions.
Spending time in natural spaces has been found to improve mental well-being, but different people experience and benefit from nature differently. This study provides the first evidence for a genetic component to both our predispositions towards nature and our tendency to visit natural spaces.
Nature-oriented people may actively seek out nature even if it means traveling from their home, but diverse urban planning is needed to provide access to natural spaces and the benefits they offer, the authors say.
“Spending time in nature links to better health and well-being,” adds Chang. “A twin study shows that a person’s desire to be in nature and how often they experience it are influenced by both genes and personal experiences.”
The authors conclude that their study demonstrates genetic contributions to the nature experiences of individuals and opens a new dimension for the study of human-nature interactions in future.
By Alison Bosman, Earth.com Staff Writer