More accurately, Darwin had eugenic views, which others popularized and adapted for their own social agendas. His cousin developed those views, which included biometrics. One school of biometrics was phrenology. A certain Charles Taze Russel published his views about phrenology in his religious newsletter.
In the Watchtower he made claims that if a dog's head was shaped like a man's, the dog would think as a man and that one's desire to worship God was due to the shape of their brain.
And that, boys and girls, is why this is a classic pot-kettle situation we are dealing with here.
The two Chucks