His specialist knowledge of mammalian dentition led him to pursue the same path with regard to human evolution and he came to be regarded as the world's leading expert on the evolution of human dentition, a reputation secured by the 1922 publication of The Evolution of the Human Dentition.
His specialized knowledge of mammalian dentition guided him to explore a similar path in human evolution, earning him recognition as the world's foremost expert on human dentition. This reputation was solidified by his 1922 publication titled "The Evolution of the Human Dentition."