The Bible narrates the story of Great Flood engulfing the world during Prophet Noah. It was a universal flood. Only Noah, his family and whatever on the Ark were saved. They repopulated the earth. Thus, people nowadays are all descended from him.
The Quran has similar story. But opinions vary as to whether this was a regional or global phenomenon.
Modern scholars such as Harun Yahya seem to indicate that it was regional, since Quran mentions Noah was sent to his people. If Noah was sent to his people, then by logic, there were other people not reached by Noah. Scholars in the earlier times, such as Ibnu Katsir and Ibnu Tabari, seemed to suggest that it was universal, taking the tradition from Ibnu Abbas as their authority.
If we go with the modern scholars, then only some of us are descended from Noah. If we go with the earlier scholars, then all of us are the descendants of Noah and those in the Ark.
The evolution scientists, on the other hand, would not debate one way or another, because they treat the story of great deluge as mere legend. Whether Noah or Adam, these are not our real ancestors. We share our common ancestry in monkey, you see.
If you ask me, I really don’t care whether the great deluge was regional or global. Personally I am inclined to believe that it was regional, but affected all people on the face of the earth, on account that humans were not yet well spread at that time. The correct answer lies only with Allah. We can only speculate.
But one thing amuses me. In the course of my research some years back on this subject, I came across what is known as The Legends of Great Flood. Apparently, in about all cultures, tribes and nations, they have stories of great deluge in one version or another.
One author by the name H.S. Bellamy in Moons, Myths and Men, estimates that altogether there are over 500 flood legends worldwide. These not only cover great nations like Chinese, Indians, Europeans, Arabs, Persians, and various Turkish tribes, but also obscure tribes in Africa, Asia, Pacific Islands, the two continents of Americas as well as Australia.
In fact, we have similar stories among tribes familiar only to us in our part of the world.
The Malays who are Muslims would go with the story in the Quran, but our aborigines such as Jakun apparently have their legend as well.
Their story goes something like this.
The ground that we stand on is merely a skin. Underneath is all water. Long ago, the god Pirman broke up this skin. As a result, the whole world was flooded. But Pirman had created a man and woman and placed them in a completely closed ship. All mankind are descended from that first pair.
The Mandayas, a tribe in the Philippines, also have their stories: A great flood once drowned all the world's inhabitants except one pregnant woman. She prayed that her child would be a boy, and it was. When he grew up, he wed his mother, and all Mandayas are descended from them.
The story that I find most interesting comes from Tibet. Long time ago, Tibet was almost totally inundated, until the god Gya took compassion on the survivors, drew off the waters through Bengal, and sent teachers to civilize the people, who until then had been little better than monkeys. Those people repopulated the land.
Hundreds more stories of such nature can be found in the following link if you are curious. http://www.talkorigins.org/faqs/flood-myths.html#Apollodorus.
What I find amusing is this: all tribes or nations, be they obscure or great, seem to have a legend about the great deluge. One common theme about all these stories is that those who were saved from this great deluge had repopulated the earth. This leads to the possibility that we share common ancestry who had been affected by the great deluge. Over times, of course, the stories had changed considerably, but the memory of the great flood remained.
Earlier I said that the most interesting story seems to be the one from Tibet. Why? Because Tibet is located at the highest plane on earth. If at one time it was inundated with flood, then the flood was certainly a big one. I doubt, however, that the flood as mentioned in the Bible and the Quran took place there, but it is interesting to know that even the Tibetans had the memory of the Great Flood.
In the Tibetan story, the most interesting part contains in the last line. After the flood, the teachers came to teach them manners. Hitherto, they had only been little better than monkeys.
Little better than monkeys? One wonders where Darwin had his monkey theory from. Not from Tibet I am sure.