Most historians and archaeologists maintain that civilization as we know it began about 5,000 years ago with the emergence of the earliest Egyptian dynasty. But, a small yet persuasive number of scientists believes that a highly advanced civilization, nearly twice as old, flourished during the last Ice Age. Solid evidence of this 10,000-year-old civilization is difficult to produce, but some feel a recent discovery off the coast of a tiny Japanese island, Yonaguni, may be the proof they seek.