Heart disease kills about a half-million people every year in the United States. It begins with the clogging of the arteries - which is called atherosclerosis. When there is too much saturated fat and trans fat in the bloodstream, it sticks to the walls, which narrows the passageway that blood must travel through.
The earliest known fossil of a human ancestor, a female Ardipithecus ramidus specimen nicknamed Ardi, is 3.2 million years old. Scientific evidence says that the first modern humans, Homo sapiens, appeared more than 200,000 years ago. Some fossils from the middle Pleistocene period (about 400,000 years ago), referred to as Homo sapiens rhodesiensis, may be archaic Homo sapiens - a transitional species.
Over the past two years, breakthroughs in ancient genomics and archaeology have revolutionized the story of the first humans in Europe â who are thought to have appeared some 45,000 years ago â and their relationship with the Neanderthals, who vanished from the region some 5,000 years afterwards.