“There cannot be a more important event than the greening of the world, for it prepared the way for everything that happened on land thereafter in the evolutionary theatre. A love of green is not just a sentimental attachment to rural holidays remembered from youthful days, green days. It runs deeper than that. In desert countries the rich sheikh celebrates his fortune with a garden sequestered away from the sun. We admire grandeur in wild scenery, mountains, canyons, deserts and glaciers. In such territory eventually this majesty begins to pall; a vague sense of dissatisfaction creeps in. Something is missing. But in greenness there is repose. It has been proved that the green wavelengths are least irritating to the retina. Red is angry, blue is cold, but green is restful.”

—Richard Fortey, Life: A Natural History of the First Four Billion Years of Life on Earth, 1998.