If we are all descendants of Prophet Noah, why do we have so many races?
In some narrations, the existence of differences in the color of the mud from which Adam and Eve were created, has been introduced as the cause of the difference in the color and race of human beings. The Messenger of God, may God bless him and grant him peace, was asked: ... Was Adam created from all mud or from a single mud? The Imam said: Of all the flowers, and if it had been created from a single flower, some people would not have known others (that is, they would all be alike).
A hadith from Imam Ali (as) has been narrated about the difference between human beings: “The reason for the difference between different people is their nature. Because from the beginning, human beings were a combination of salty and sweet soil, hard and soft ... one beautiful and short-sighted, another tall and low-minded, and one ugly and virtuous, and one short and well-thought-out, and one pure in nature and immoral. ... »
In some hadiths, the prayer of Prophet Noah (pbuh) is introduced as the cause of differences between races and colors. In the commentary of Noor al-Thaqalin, he narrates from Hazrat Abdul Azim Hasani: I heard Ali ibn Muhammad Asgari (peace be upon him) say: He prayed for them and said: خ "O God, change their crucifixion so that only black children will be born from their crucifixion ..."
But from the Qur'anic point of view, the will of God Almighty is that human beings are different in terms of color, race and shape. God, who is able to create man from inanimate mud, can make some of Adam's children black and some white, etc., for his personal and social interests. It is stated in Surah Al-Hujurat: "O people, We created you from a male and a female, and made you into great clans and small clans, that you may know one another."
And in verse 22 of Surah Romans, God Almighty expresses the difference of languages and colors as signs of His power.
Ref:https://hawzah.net/fa/Question/View/65359/