The story of Adam and Eve is just ancient Hebrew myth, and the races did not take the last 6000 years to appear. They have been in existence for a lot longer than that.
The races developed from a group of early humans who left Africa several tens of thousands of years ago. As they spread out and entered different environments in their migrations, they adapted by the evolutionary process of natural selection to those environments.
Those who entered what is now northern Europe and western Asia became lighter skinned so they could absorb the ultra-violet light easier from the weaker sun in that area to manufacture vitamin D. These people became the Caucasians.
The people who remained in Africa retained their darker skin and tight-curled hair that protected them from the tropical sun. Because the sun is so strong there, their skin did not have any problem manufacturing vitamin D.
As for the other races. Some of the early group of humans who left Africa eventually entered the east Asian highlands had to contend with the glaring sun on the ice and snow fields (there was still an Ice Age at the time which resulted in mostly year-round winter conditions in that area). The narrow eyes they developed helped to see in the glare (Eskimos made sun shields for their eyes that also used narrow slits for that same purpose). They also developed flattish, fat-padded faces to minimize heat loss. These people became the Orientals who spread out over most of eastern Asia.
An early group of the Orientals that had not yet developed the complete range of oriental features migrated to the New World across the Bering land bridge (which existed at that time because the sea levels were lower as a result of much of the earth's water being tied up in glaciers) and became the American Indians.
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@Love Thy Neighbor, evolution doesn't make sense to you because you don't know squat about it. There is a massive amount of evidence for it if you bother to actually study it instead of mindlessly believing what you find in the Bible and LSoS creationist web sites.
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@Michael, the flood is just another ancient Hebrew myth and never occurred. It is contradicted by both history and the geologic record.
The history of ancient Egypt is well known from their writings and archaeological findings.
"The history of Ancient Egypt spans the period from the early predynastic settlements of the northern Nile Valley to the Roman conquest in 30 BC. The Pharaonic Period is dated from around 3200 BC, when Lower and Upper Egypt became a unified state, until the country fell under Greek rule in 332 BC."
"Between 5500 and 3100 BC, during Egypt's Predynastic Period, small settlements flourished along the Nile, whose delta empties into the Mediterranean Sea. By 3300 BC, just before the first Egyptian dynasty, Egypt was divided into two kingdoms, known as Upper Egypt, Ta Shemau, to the south, and Lower Egypt, Ta Mehu, to the north.[7] The dividing line was drawn roughly in the area of modern Cairo."
"The Old Kingdom is most commonly regarded as spanning the period of time when Egypt was ruled by the Third Dynasty through to the Sixth Dynasty (2686 BC – 2134 BC). The royal capital of Egypt during the Old Kingdom was located at Memphis, where Djoser established his court. The Old Kingdom is perhaps best known, however, for the large number of pyramids, which were constructed at this time as pharaonic burial places. For this reason, the Old Kingdom is frequently referred to as "the Age of the Pyramids." The first notable pharaoh of the Old Kingdom was Djoser (2630–2611 BC) of the Third Dynasty, who ordered the construction of a pyramid (the Step Pyramid) in Memphis' necropolis, Saqqara."
"The Fifth Dynasty began with Userkhaf (starting c. 2495 BC) and was marked by the growing importance of the cult of sun god Ra."
"During the sixth dynasty (2345–2181 BC), the power of pharaohs gradually weakened in favor of powerful nomarchs (regional governors). These no longer belonged to the royal family and their charge became hereditary, thus creating local dynasties largely independent from the central authority of the pharaoh. Internal disorders set in during the incredibly long reign of Pepi II (2278–2184 BC) towards the end of the dynasty."
"By 2160 BC a new line of pharaohs (the Ninth and Tenth Dynasties) consolidated Lower Egypt from their capital in Herakleopolis Magna. A rival line (the Eleventh Dynasty) based at Thebes reunited Upper Egypt and a clash between the two rival dynasties was inevitable. Around 2055 BC the Theban forces defeated the Heracleopolitan Pharaohs, reunited the Two Lands. The reign of its first pharaoh, Mentuhotep II marks the beginning of the Middle Kingdom."
And it continues for long after that.
http://en.wikipedia.org/wiki/History_of_ancient_Egypt
According to Answers in Genesis:
"Calculated BC date for the Flood: 2348"
http://www.answersingenesis.org/articles/2012/03/09/feedback-timeline-for-the-flood
So, why weren't the ancient Egyptians drowned in the mythical biblical flood and the pyramids filled with water and mud?
The fact of the matter is that the book of Genesis is myth-based. The ancient Israelites constructed their myths on the basis of their superstitions and the myths and stories of the peoples around them. They got the story of the flood from the mythical epic of Gilgamesh during their Captivity in Mesopotamia, and they modified it to fit their belief in their own god. They also interpreted the vague histories they heard of other peoples, such as the Egyptians, to make them fit into their creation myths to create the "history" of the world as they conceived it.
Of course, since they had no real knowledge of the long-past history of the peoples around them, the myths they constructed frequently conflict with reality. Such is the case with the flood myth and the history of the ancient Egyptians.
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As for the geologic evidence against the flood, see my answer here.
https://answersrip.com/question/index?qid=20130916150318AAZEvH9