Paleontologist who all influenced Contemporary Synthesis, which played a significant function in creating an established account of progression. He was also the Curator from the Section of Geology and Paleontology on the American Museum of Organic History from 1945 to 1959. He started his career posting academic documents about fossils and their taxonomy. He proved helpful at many educational establishments, including at Harvard being a curator from the Museum of Comparative Zoology. He was created in Chicago. He was receiver of the Darwin-Wallace Medal, that was called after scientist Charles Darwin.