Which naturalists were alive in the 1800s?

Several prominent naturalists were alive in the 1800s, including Charles Darwin, who developed the theory of evolution by natural selection, and John Muir, known for his work in conservation and the natural history of the American wilderness. Other notable figures include Alfred Russel Wallace, who independently conceived the theory of evolution, and Alexander von Humboldt, whose explorations and writings significantly influenced the fields of ecology and biogeography. Additionally, naturalists like Louis Agassiz and Thomas Henry Huxley contributed to the understanding of geology and Biology during this period.