In 1984, American biologist Edward O Wilson published his book Biophilia, in which he argued that humans have an innate bond with other living systems. Since then, researchers have found that a connection to nature can lower blood pressure, reduce stress, improve attentiveness, boost creativity and make us generally happier people. And yet the past two centuries of urbanisation have nearly severed our ties with nature, eliminating it from our lives in the worst cases and at best reducing it to decoration – a flower pot on the windowsill, a garden weeded, pruned and rid of pests.