He developed Lamarck's and Erasmus Darwin's ideas of transmutation and evolutionism, and investigated homology, even proposing that plants and animals had a common evolutionary starting point.
Ia mengembangkan gagasan transmutasi dan evolusionisme Lamarck dan Erasmus Darwin, dan menyelidiki homologi, bahkan mengusulkan bahwa tumbuhan dan hewan memiliki titik awal evolusi umum.