The story of Noah is widely circulated in western civilization. I have no doubt that it is based on a flood. I have strong doubts that the flood was global, but floods do occur. The Babylonians had a similar story about Gilgamesh and Ut-Napishtim. Rivers were certainly important to early humans, and the weather everywhere is variable. Genesis 6 ad 7 describe the story of Noah and God's commandment. There is a difference between the specs in Genesis 6 and the as-built in Genesis 7. Two of every animal is probably not enough to ensure the continuance of a species since there are accidents and predation, not to mention problems feeding herbivores after a flood. (I recall a cartoon showing a pair of unicorns who got to the launch point after the ship had sailed).

I am not familiar with legends in other areas of the world but I would not be surprised to hear that there are other such stories in other civilizations.

[not to be taken in offence, Jerry] I wish no one had posted about this topic at any time. It is nonsense to me.
What color wine. Wine can be made from blue berries or similar. In California we sometimes have a red tide condition due to an algae that make the water red and also poisons many other forms of sea life for a week to several at a time. I have no idea if there are red tides near Greece but there is a Red Sea not too far away. I think changes in human physiology over such a short period of human history is the last explanation I would look at.