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.
Scientists have unearthed the jawbone of what they claim is one of the very first humans. The 2.8 million-year-old specimen is 400,000 years older than researchers thought that our kind first emerged.The discovery in Ethiopia suggests climate change spurred the transition from tree dweller to upright walker.cientists have unearthed the jawbone of what they claim is one of the very first humans. The 2.8 million-year-old specimen is 400,000 years older than researchers thought that our kind first emerged.