The species theory, polygenism, held that human races were of different lineages and suggested a hierarchy outlined in the Chain of Being that positioned Africans between man and lower primates.
No, they are involved in the Circulatory System which is responsible for pumping and channelling blood to and from the body and lungs with heart, blood and blood vessels. no veins are not considered an organ because they are a grouping of different tissues like a organ.
Definition of vein. 1  1 : blood vessel; especially : any of the tubular branching vessels that carry blood from the capillaries toward the heart. 2  2a : any of the vascular bundles forming the framework of a leafb : any of the thickened cuticular ribs that serve to stiffen the wings of an insect.