Wilderness or wildland is a natural environment on Earth that has not been significantly modified by human activity. It may also be defined as: 'The most intact, undisturbed wild natural areas left on our planet—those last truly wild places that humans do not control and have not developed with roads, pipelines or other industrial infrastructure.' The term has traditionally referred to terrestrial environments, though growing attention is being placed on marine wilderness. Recent maps of wilderness suggest it covers roughly one quarter of Earth's terrestrial surface, but is being rapidly degraded by human activity. Even less wilderness remains in the ocean, with only 13.2% free from intense human activity. Some governments establish them by law or administrative acts, usually in land tracts that have not been modified by human action in great measure. The main feature of them is that human motorized activity is significantly restricted. These actions seek not only to preserve what already exists, but also to promote and advance a natural expression and development. Wilderness areas can be found in preserves, conservation preserves, National Forests, National Parks and even in urban areas along rivers, gulches or otherwise undeveloped areas. These areas are considered important for the survival of certain species, biodiversity, ecological studies, conservation, solitude, and recreation. Wilderness is deeply valued for cultural, spiritual, moral, and aesthetic reasons. Some nature writers believe wilderness areas are vital for the human spirit and creativity. They may also preserve historic genetic traits and provide habitat for wild flora and fauna that may be difficult to recreate in zoos, arboretums or laboratories. The word wilderness derives from the notion of 'wildness'—in other words, that which is not controlled by humans. The mere presence or activity of people does not disqualify an area from being 'wilderness.' Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered 'wild.' This way of looking at wilderness includes areas within which natural processes operate without human interference. The WILD Foundation states that wilderness areas have two dimensions: they must be biologically intact and legally protected. The World Conservation Union (IUCN) classifies wilderness at two levels, Ia (Strict Nature Reserves) and Ib (Wilderness Areas). Activities on the margins of specific wilderness areas, such as fire suppression and the interruption of animal migration also affect the interior of wildernesses. Especially in wealthier, industrialized nations, it has a specific legal meaning as well: as land where development is prohibited by law. Many nations have designated wilderness, including the United States, Australia, Canada, New Zealand, and South Africa. Many new parks are currently being planned and legally passed by various Parliaments and Legislatures at the urging of dedicated individuals around the globe who believe that 'in the end, dedicated, inspired people empowered by effective legislation will ensure that the spirit and services of wilderness will thrive and permeate our society, preserving a world that we are proud to hand over to those who come after us.' Looked at through the lens of the visual arts, nature and wildness have been important subjects in various epochs of world history. An early tradition of landscape art occurred in the Tang Dynasty (618-907). The tradition of representing nature as it is became one of the aims of Chinese painting and was a significant influence in Asian art. Artists in the tradition of Shan shui (lit. mountain-water-picture), learned to depict mountains and rivers 'from the perspective of nature as a whole and on the basis of their understanding of the laws of nature… as if seen through the eyes of a bird.' In the 13th century, Shih Erh Chi recommended avoiding painting 'scenes lacking any places made inaccessible by nature.' For most of human history, the greater part of the Earth's terrain was wilderness, and human attention was concentrated in settled areas. The first known laws to protect parts of nature date back to the Babylonian Empire and Chinese Empire. Ashoka, the Great Mauryan King, defined the first laws in the world to protect flora and fauna in Edicts of Ashoka around 3rd Century B.C. In the Middle Ages, the Kings of England initiated one of the world’s first conscious efforts to protect natural areas. They were motivated by a desire to be able to hunt wild animals in private hunting preserves rather than a desire to protect wilderness. Nevertheless, in order to have animals to hunt they would have to protect wildlife from subsistence hunting and the land from villagers gathering firewood. Similar measures were introduced in other European countries. The idea of wilderness having intrinsic value emerged in the Western world in the 19th century. British artists John Constable and J. M. W. Turner turned their attention to capturing the beauty of the natural world in their paintings. Prior to that, paintings had been primarily of religious scenes or of human beings. William Wordsworth’s poetry described the wonder of the natural world, which had formerly been viewed as a threatening place. Increasingly the valuing of nature became an aspect of Western culture.