A case of people conforming emerging science, data and information to suit their world view. This type of psuedo-science has always existed, unfortunately. We see it with craniometry in regards to race. Prominent scientists even asked to have their brains weighed after their death in order to display their prowess.

So eager are people to use "science" to reinforce their world view that they'll take guidelines for portraiture, in the case of Petrus Camper's "Facial Angle" research, and use it to conclude that Africans and Asians capacity is closer to apes.

Petrus Camper is also known for his theory of the "facial angle" originally in connection with two lectures he gave in Amsterdam in 1770 to art students on beauty and portraiture. He was concerned with the fact that all artists painted the black Magus in the nativity with Caucasian face. He determined that modern humans had facial angles between 70° and 80°, with African and Asian angles closer to 70°, and European angles closer to 80. According to his new portraiture technique, an angle is formed by drawing two lines: one horizontally from the nostril to the ear; and the other perpendicularly from the advancing part of the upper jawbone to the most prominent part of the forehead. He claimed that antique Greco-Roman statues presented an angle of 100°-95°, Europeans of 80°, 'Orientals' of 70°, Black people of 70° and the orangutan of 42-58°, but not in an overtly racist fashion-he merely claimed that, out of all human races, Africans were most removed from the Classical sense of ideal beauty. These results were later used as scientific racism, with research continued by Étienne Geoffroy Saint-Hilaire (1772–1844) and Paul Broca (1824–1880). Camper, however, agreed with Buffon in drawing a sharp line between human and animals (although he was misinterpreted by Diderot, who claimed that he was a supporter of the Great Chain of Being theory

When people want to "believe" something, they'll find ways to support it.