Cities are the main human ecosystem – 60 per cent of us now live in metropolitan areas with more than 100,000 people – but they also make us sick, depressed and anxious. By contrast, being around blue water, green trees and space makes us healthier, more productive, even more generous – a positive effect known as “biophilia.”
For her graduate work at the University of Washington, Judith Heerwagen, an evolutionary psychologist, studied the living conditions of the macaque monkeys at Seattle’s Woodland Park Zoo. At the time, the zoo was bringing in biologists and botanists to design better landscapes for the animals, including an African savannah where several species might live together as they did in the wild. The effect on the monkeys, she says, was noticeable: They became less aggressive, healthier.
“It was just an ‘aha!’ moment,” says Dr. Heerwagen, now an environmental consultant in Seattle. “We do a better job building zoos for animals than buildings for people.”
If the hubbub of cities heightens anxiety – as recent German research suggests – then nature is Valium. There’s a near-universal calm in the rustle of wind in the trees and the steady slosh of an ocean tide. In the Netherlands, researchers call it Vitamin G, as in “green.”