During the approximate period of the 1880s to about 1920, sometimes called "the eclipse of Darwinism", scientists proposed various alternative evolutionary mechanisms which eventually proved untenable.
Durante o período de 1880 a 1920, que ás veces se denomina "a eclipse do darwinismo", os científicos propuxeron varios mecanismos evolutivos alternativos que finalmente se probou que eran insostibles.