Georges-Louis Leclerc, Comte de Buffon suggested that species could degenerate into different organisms, and Erasmus Darwin proposed that all warm-blooded animals could have descended from a single microorganism (or "filament").
Buffon suxeriu que as especies podían dexenerar orixinando diferentes organismos, e Erasmus Darwin propuxo que todos os animais de sangue quente puideron descender dun só microorganismo (ou "filamento").