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.
National Geographic News. Perhaps the world's most famous early human ancestor, the 3.2-million-year-old ape Lucy was the first Australopithecus afarensis skeleton ever found, though her remains are only about 40 percent complete (photo of Lucy's bones).iscovered in 1974 by paleontologist Donald C. Johanson in Hadar, Ethiopia, A. afarensis was for about 20 years the earliest known human ancestor species (Africa map).