'Savages', with high cheekbones, protruding jaws and low morals were to be found not only in Africa, or even in Ireland, but in the white urban underclass of Britain itself.
This perspective, and the racist prejudices it empowered, would be discredited in later decades so it is fascinating to read this study arguing that criminals do indeed have common physical traits. Naci Mocan and Erdal Tekin from the University of Colorado and Georgia State University respectively point out that criminals tend to be uglier than average. Rather than ugliness itself signalling a criminal personality, they point to the tendency for more attractive people to earn more and enjoy better opportunities compared with uglier people:
...I seemed to see all of a sudden, lighted up as a vast plain under a flaming sky, the problem of the nature of the criminal - an atavistic being who reproduces in his person the ferocious instincts of primitive humanity and the inferior animals. Thus were explained anatomically the enormous jaws, high cheekbones, prominent superciliary arches, solitary lines in the palms, extreme size of the orbits, handle-shaped ears found in criminals, savages and apes...
Being very attractive reduces a young adult’s propensity for criminal activity and being unattractive increases it. Being very attractive is also positively associated with wages and with adult vocabulary test scores, which implies that beauty may have an impact on human capital formation. The results suggest that a labor market penalty provides a direct incentive for unattractive individuals toward criminal activity.
One consequence of this is that the outdated old Victorian assumptions about certain people looking "shifty" and seeming likely criminals may have had a little value after all, if not for the reasons they assumed.
Another implication is that there is a disadvantaged group in modern society who get little attention or support. While inequalities in race, sex or sexuality are denounced, the disproportionate poverty of ugly people is rarely mentioned.