All humans descend from the same father and mother, 'Aadam (Adam) and Hawwaa’ (Eve), may Allaah exalt their mention, so why do they differ so much in the way they look, Chinese, Europeans and Africans?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

It was reported on the authority of Abu Moosa Al-Ash’ari that the Prophet, sallallaahu ‘alayhi wa sallam, said that Allaah The Exalted created 'Aadam from a handful of dust taken from the whole earth.  Thus, the sons of 'Aadam vary as the earth varies and are white, red, black and colors in between. Additionally, some of them are lenient and others are harsh, and some are wicked and others good. [Ahmad, Abu Daawood, At-Tirmithi and Al-Haakim]

Commenting on this Hadeeth Al-Mubaarakfoori mentioned that the meaning of this Hadeeth (narration) is that ‘Aadam was created from a handful of earth collected by angels from the entire planet earth upon the command of  Allaah The Exalted. Therefore, Adam’s offspring vary in color and features, just like areas of the earth vary. Some are red, others white and others black according to the part of the earth from which they were created. These three colors are the origin of all other colors, because the other races originated from these three.  Furthermore, he added, some of them are lenient and others are harsh and wicked and some of them have evil characteristics and others good, according to the part of the earth from which they were created. Allaah The Exalted decreed the difference in colors, features and creation. 

At-Teebi mentioned that the meaning of this Hadeeth is that some humans are kind and lenient, while others are harsh. Moreover, some are good and they are the believers who are beneficial, like the good and beneficial parts of the earth. Al-Teebi further explained that the good are the believers and the evil are the disbelievers who resemble an infertile piece of land  that does not benefit from water and even spoils it   

In sum, diversity in colors and looks is due to the diversity of the earth from which people were created. 

Allaah Knows best.