NATURAL SELECTION. The evolution idea is as old as the time of the Greek phi losophers., but that form of it called natural seleetion, or Darwinism, dates from 1S5S, when the theory was stated by Darwin (q.v.) and also by Wallace (q.v.), each independently of the other. Nearly a century earlier Billion, and afterwards Erasmus Darwin. had suggested that species were mutable, and that all living beings had descended from some primitive type or germ, the transformation having been effected by changes of climate, food, exercise, and so on. But the real founder of the modern theory of organic evolution was Lamarck (q.v.; see also LAmmtrKism). The chief agents or factors of organic evolution which he proposed were changes of environment, of Militate. sMI, food, tempera ture. use, and disuse, while he briefly mentions the agency of competition. the results of geo graphical isolation, and the swamping effects of crossing, besides use-inheritance. AlthomM sup ported by a few, though well-selected, facts. La marck's views were, owing to the influence of ("twirl., and the deep-seated prejudice of the
times, ignored and well-nigh forgotten, except to be called up and ridiculed. Yet between the date of Lamarck's death in 1829 and shortly be fore IS5S nearly thirty naturalists, most of them of eminence, had publicly enunciated in a tentative way evolutional views—among them Grant, Wells, Naudith Self aallhansen, \\ allace in 1855, and others. Alcanwhile Hutton and Lvell had advanced uniformitarian views in geology. Progress in the knowledge of the flora and fauna of the earth had greatly increased. The cell doctrine hail been advanced; the sciences of paleontology, and morphology had been founded and were rapidly gaining ground.
As early as March, 1852, Herbert Spencer, in an essay published in the Leadcr, advocated the theory of the modification of species by changes of environment, and a few years later adopted the word 'evolution.' applying, it to psychology, and later to sociology and comparative religion.