Recent research suggests that spending time in nature actually makes people "more caring." The studies, by University of Rochester psychologists Netta Weinstein, Andrew Przybylski, and Richard Ryan, showed that people exposed to nature (well, mostly slideshows of nature) put a higher value on intrinsic aspirations, such as doing good in the world or having meaningful relationships, and lower value on extrinsic aspirations, like making a lot of cash or admired by many people. Now as I mentioned, the participants didn't actually live outdoors for a while or anything as part of the study. Rather, in three of the studies, they looked at images of either the built environment or landscapes and such. And in the fourth, some participants were assigned to work in a laboratory either with or without plants around them. Then they answered a series of questions or were given tests of generosity. "The result? People who were in contact with nature were more willing to open their wallets and share. As with aspirations, the higher the immersion in nature, the more likely subjects were to be generous with their winnings."
From the University of Rochester:
Why should nature make us more charitable and concerned about others? One answer, says coauthor Andrew Przybylski, is that nature helps to connect people to their authentic selves. For example, study participants who focused on landscapes and plants reported a greater sense of personal autonomy ("Right now, I feel like I can be myself"). For humans, says Przybylski, our authentic selves are inherently communal because humans evolved in hunter and gatherer societies that depended on mutuality for survival."Nature Makes Us More Caring, Study Says" (University of Rochester)
In addition, write the authors, the richness and complexity of natural environments may encourage introspection and the lack of man-made structures provide a safe haven from the man-made pressures of society. "Nature in a way strips away the artifices of society that alienate us from one another," says Przybylski.
"Can Nature Make Us More Caring? Effects of Immersion in Nature on Intrinsic Aspirations and Generosity" (paper abstract)
"The Moral Call of the Wild" (Scientific American, thanks Marina Gorbis!)