Wilson noted that there is a primal biological need of our species, this can impact our material and physical maintenance, but also on the human craving for aesthetic, intellectual, cognitive and even spiritual meaning and satisfaction.
He also identified that this is inherent, a part of our species' evolutionary heritage, and has an association with human competitive advantage.
The ‘biophilia’ effect is the theory that explains why nature is so therapeutic.
Humans have almost a genetic response to ‘greenness’ – the feeling of relaxation and comfort in a green environment it is therefore incorporated into our genes for survival. Humans have evolved in a close relationship with the natural environment and are therefore closely attuned to nature, it is then that our sensitivity to life and life‐like processes become deeply embedded in our development because there is a competitive advantage. Biophilia is a big-picture hypothesis that has stimulated others to create a practical understanding of the connection between humans and other species and the question of how important is it to 21st-century humans.
It may sound a bit convoluted as an idea, however simply put Wilson suggests that as we evolved from species that was so linked to nature and through the much longer period of human evolution within nature, it became part of our biological makeup, influencing behaviour and preference, and therefore our affinity to nature is actually part of evolution.