NE'O-LAMARCWISM. The modified doc trine held by those naturalists who accept in the main the teachings of Lamarck ( q.v. ) . La marck was the first truly scientific thinker to state in a detailed way the enlists not only of the origin of species. but of certain types of animal life, such as some orders of birds, of the groups represented by the al, honor. the kanga roo, and so on. The chief Lamarekian factors of organic evolution (see LAMARCKISM) are changes in the environment. direct in plants awl the low est. animals, indirect in the higher animals; also, the use and disuse of organs, and the trans mission of characters acquired during the life time of the individual. or what is called 'use inheritance.' The first writer after Lamarck. on the lines laid out by the great French zoOlogist. was Herbert Spencer. In 1866-71. in his Prin ciples of nirdogy. 11:ieekel claimed (18681 that we should have to adopt Lamarek's theory of descent for the explanation of biological phe nomena. "even if we did not possess Darwin's theory of selection," adding: "The one is so com pletely and directly prored by the other, established by mechanical causes, that there re mains nothing to he desired." In America. rope ( 1866-71) and Hyatt (1866 7-1) independently advocated Lamarekian views.
Cope tirst ) furnished what he considered as "an actual demonstration of the reality of the Immarekian factor of 11:,e. or motion. as frie tion, impact. and strain. as an efficient cause of evolution." A. S. Packard ( s7I ), by his studies of the embryology of Limulus, and of cave ani mals. was led III adopt Immarekian views in
preference to the theory of natural selection, Which never seemed to him adequate or suffi ciently eomprehensive to explain the origin of variathms and the rise of new types: and it was he who originated the term Yen-in/nun-kb:la. "Neu lamarekism," he explained. no and makes use of the factors both of the Saint-Ililaire and Immarekian schools, as containing the more fundamental causes of variation, and adds those of geographical isolation or segregation (Wagner and Gulick). the effects of gravity, the effects of current- of air and of water, of fixed or seden tary as opposed to active modes of life, the results of strains and impacts ( Eyder, Cope. and Osborn), the principle of change of function as inducing the format ion of new structures (Dohrit), the effects of parasitism, rommensa1 ism. and of symbiosis in short, the biological environment: together with geological extinction• natural and sexual selection. and hybridity." Among American zoologists wtfo have advo cated Immarekian views. are W. II. Dail, J. A. Allen. 11. T. ,Jackson, C. II. Eigenmann. and others: in England. Spencer, Ilenslow, Cunning ham. Gadow, and others: in France. Giard, Perrier: 811(1 in (:ermany and lIolland. Ilaeekel, \Vm.rner, Eimer. Standfuss, Fischer, Plate. Pfeffer. 0. Ilertwig. Emery, faux, and others..