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.
Vein of Galen Malformation. Vein of Galen malformations (VOGMs) are a type of disorder known as cerebral vascular malformations, which affect the blood vessels in the brain. VOGM is a rare vascular malformation of the brain that develops before birth and is sometimes diagnosed in the womb or soon after birth. These malformations can involve the arteries, the blood vessels that carry blood to the body, or the veins, the blood vessels that return blood to the heart. They occur occur when there is an abnormal connection between arteries and the deep draining veins.