In the late 1900s researchers like E.O. Wilson and Stephen Kellert began using the term "biophilia" to describe the basic love of other living things that humans seem to exhibit–an affection that encompassed nature, other species, diversity. So strong an affinity, so powerful an affect, was biophilia that the researchers decided it must be instinctive, built into the human brain by natural selection because it was an aid to survival.
Or else it's part of God's (intelligent, by definition) design–to make gardeners who love the garden. I'm betting on the latter hypothesis.
But there's a competing impulse, a dark attraction that fights for the affection of humans. Is it money? Sex? Power?
No, it's actually video screens. There is a strong negative relationship between the amount of time people spend on the Internet, playing video games, and watching television and movies, and the amount of time people spend outside in nature. Humans seem to have a (built-in? instinctive?) love of flat screen TVs and handheld video devices.
Biophilia is being replaced by videophilia.