Tilly Edinger (1897-1967) was born Johanna Gabrielle Ottelie Edinger and is recognized as a pioneer in the field of paleoneurology, which is the study of the brain through fossil remains. Her major work is titled Evolution of the Horse Brain.

Edinger applied her knowledge of neurology to the study of paleontology to determine how the brains of a species evolved. Because brains decompose, she focused on the study of the fossilized remains of the skulls and cranial cavities of many species to hypothesize that brains of any given species evolve differently based upon immediate external stimuli. Rejecting previous scientific notions from the eighteenth- and nineteenth-centuries, which asserted that evolution was a linear progression resulting in such lower animals as rodents eventually evolving into higher beings such as humans, Edinger postulated that evolution follows a complex branching process. This is a process by which different environmental factors that include...