Though the skulls and knees, for instance, are different between races. It doesn't mean that people of one race are smarter because of skull size or shape, but

Though the skulls and knees, for instance, are different between races. It doesn't mean that people of one race are smarter because of skull size or shape, but the bones do have the shape discernibly different. Similarly you don't dismiss chemistry just because it has unscientific alchemic roots.