Science and Medicine
Carl Georg Lucas Christian Bergmann (18 May 1814 – 30 April 1865), also known as Karl Georg Lucas Christian Bergmann, was a German anatomist, physiologist, and biologist. He developed Bergmann's rule (that populations and species of animals of larger size are found in colder environments). He microscopically examined the cells of the retina to determine which of them convert light into neural signals that lead ultimately to visual perception: the cones and the rods. Bergmann also coined the terms fovea centralis (for the very center of the retina), homoiothermic (referring to warm-blooded animals), and poikilothermic (referring to non-homoiothermic animals).
1991 eruption of Mount Pinatubo.
Francis Trevelyan Buckland.
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