Alexander von Middendorff
Alexander Theodor von Middendorff was a Russian zoologist and explorer of Baltic German and Estonian extraction. He is known for his expedition 1843–45 to the extreme north and east of Siberia, describing the effects of permafrost on the spread of animals and plants.
von Middendorff circa 1880
Coat of arms of the Middendorff family [et], in the Baltic Coat of arms book by Carl Arvid von Klingspor in 1882.
Permafrost occurrences and southern limit of permafrost, from Karl Ernst von Baer's instructions to Middendorff, 1843
Karl Ernst Ritter von Baer Edler von Huthorn was a Baltic German scientist and explorer. Baer was a naturalist, biologist, geologist, meteorologist, geographer, and is considered a, or the, founding father of embryology. He was a member of the Russian Academy of Sciences, a co-founder of the Russian Geographical Society, and the first president of the Russian Entomological Society, making him one of the most distinguished Baltic German scientists.
Karl Ernst von Baer
Lasila manor, Estonia, where von Baer spent his early childhood
Permafrost occurrences and southern limit of permafrost according to Karl Ernst von Baer, 1843
Southern limit of permafrost according to Karl Ernst von Baer (1843), and other authors. The southern limit of permafrost as delineated by Baer in 1843 corresponds well with the actual limit defined by Jerry Brown (1998).