It is well-established that being in nature is healthy for humans both physically and mentally. Even the colour green has a calming effect on humans. Studies have found that when shown pictures of various landscapes, the savannah produces the strongest positive effect. That may be no wonder, as for 99% of our evolution, we lived on the savannah. However, we clearly also have an affinity for trees. What young child does not like to climb in trees? Indeed, climbing alone can be a passionate activity. On children’s playgrounds, the structures meant for climbing invariably have kids clambering on them. When I was a child, my favourite pastime with my younger brother was climbing in the large beech trees that grew on the property. One day my brother fell out of a tree and broke his arm. My parents took him to the hospital to have the arm set in a cast. When he got home, he and I were out climbing again, him using just one arm, to the horror of my parents. Our closest relative is the chimpanzee, and we share a common ancestor. That ancestor lived in the jungle on the African continent. Climate changed, becoming dry, and the jungle started to diminish in extent and the savannah slowly formed. Our immediate ancestors moved onto the savannah and having an upright posture and being bipedal was an evolutionary advantage. Ancestors of the chimpanzee stayed in the jungle and continued to live in the trees. The affinity of young children for climbing trees may be a trait from those early evolutionary times. Humans left Africa at least twice in our evolution and spread out across the globe, settling everywhere except for Antarctica. Humans could eventually be found in every habitat on earth, from the fidget arctic to the hot tropics. Many groups settled in forests but did not start to live in the trees again. We have not lost our affinity to savannah landscapes, but nor do I believe we have lost a connection to forests. Forests offer protection, food, material for constructing shelters, protection from the elements, and physical and psychological health. Our modern society sees forests as a wood fibre resource, and we seem intent on turning forests into tree farms for our economic benefit. Forests, however, are so much more. They sustain a vast biodiversity, produce oxygen, purify the atmosphere, and store carbon. We are also beginning to understand that forests are not just collections of trees and various other organisms. Forests are complex ecosystems where the multiple organisms interconnect through a web of exchange we are just beginning to understand. The more we can learn about forests, their intricacies, their impact on our overall health, and how to appreciate them, the better.