It has long been established that evolution is racist in nature, and has been used to justify racism. This goes back to Darwin's writings as well.
But what happens when one racist-based pseudoscience is used to support another racist-based pseudoscience? Phrenology, was pseudoscience that postulated that the size and shape of the skull indicated levels of intelligence. Although its advocates stumbled across the occasional scientific truth, the field as a whole has been long discredited. Another pseudoscience that allegedly supported phrenology was facial angle. Adding the three pseudosciences of evolutionism, phrenology and facial angle together gave strong "scientific" support for racism. To make matters worse, racist presuppositions were plugged into evolutionary biases.
A measurement technique called facial angle has a history of being used to rank the position of animals and humans on the evolutionary hierarchy. The technique was exploited for several decades in order to prove evolution and justify racism. Extensive research on the correlation of brain shapes with mental traits and also the falsification of the whole field of phrenology, an area to which the facial angle theory was strongly linked, caused the theory’s demise.
The use of the facial angle, a method of measuring the forehead-to-jaw relationship, has a long history and was often used to make judgments of inferiority and superiority of certain human races. University of Chicago zoology professor Ransom Dexter wrote that the “subject of the facial angle has occupied the attention of philosophers from earliest antiquity.” Aristotle used it to help determine a person’s intelligence and to rank humans from inferior to superior. It was first used in modern times to compare human races by Petrus Camper (1722–1789), and it became widely popular until disproved in the early 20th century.
The theory proposes that animal evolutionary history involves a progression from a nearly horizontal facial angle to a vertical one, a transition that was also used to support the evolution of ape-like creatures to humans. Facial angle was also commonly used in classifying other animals from primitive to highly evolved life-forms. Proponents of the facial angle theory hypothesized that facial angle was not only a trend from fish to humans, but could also be used to rank human groups from inferior to superior. It was a “primary instrument of scientific racism”.If you can bring yourself to face the truth, you can read the rest of "Using facial angle to prove evolution and the human race hierarchy", here.