Daniel Trembly MacDougal
Dr. Daniel Trembly MacDougal was an American botanist and writer. He is known for his work on desert ecology and as the earliest botanist to research Chlorophyll. He was the inventor of the MacDougal dendrograph, used to record changes in the volumes of tree trunks. He was a pioneer in studying the idea of Mutation Theory for controlling evolution. He helped to establish two botanical laboratories, the Desert Laboratory in Tucson, Arizona, and the Coastal Laboratory in Carmel-by-the-Sea, California.
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