Darwin was eminent as a naturalist, geologist, biologist, and author. He studied biology intently and was already an accomplished naturalist and a published ornithologist. Robert is the grandson of naturalist and animal conservationist Bob Irwin. In December 1831, he joined the "Beagle" expedition as a gentleman naturalist and geologist. Leopold was a naturalist, not a philosopher. Deering became an avid naturalist and preservationist. John Muir was a Scottish-born American naturalist and explorer. Georges Pouchet, the French naturalist and anatomist, was a polygenist. She had four children, including novelist Lawrence Durrell and naturalist and writer Gerald Durrell. The Prussian naturalist and explorer Alexander von Humboldt described it in 1826. Michel Adanson, the French naturalist and explorer who described "Adansonia digitata". He was the eldest brother of naturalist and writer Gerald Durrell. His attainments as a writer and naturalist will survive. These programs include Outdoor Adventure, Outdoor Adventure Naturalist and Forestry Technician. Most Beautiful was taken from the writings of English naturalist Charles Darwin.