‘Most new species, genera, and families, and nearly all categories above the level of families, appear in the records suddenly and are not led up to by known, gradual, completely continuous transitional sequences.’
George Gaylord Simpson, Ph.D. (Vertebrate Paleontology) (Was Agassiz Professor of Vertebrate Paleontology, Museum of Comparative Zoology, Harvard University and also Professor of Geology at the University of Arizona, Tucson) in ‘The Major Features of Evolution’, 1953, p.360.