Arabs look down upon people with darker skin than they do.
This stems directly from Islamic teachings which teach that Arabs are the "Master Race":
Arabs are the most noble people in lineage, the most prominent, and the best in deeds. We were the first to respond to the call of the Prophet. We are Allah’s helpers and the viziers of His Messenger. We fight people until they believe in Allah. He who believes in Allah and His Messenger has protected his life and possessions from us. As for one who disbelieves, we will fight him forever in Allah’s Cause. Killing him is a small matter to us.
"A man married a maid-slave who bore him a child. Would that child be free or would he be an owned slave?" "Her child whom she bore from him would be the property of her master according to all the Imams (heads of the four Islamic schools of law) because the child follows the (status) of his mother in freedom or slavery. If the child is not of the race of Arabs, then he is definitely an owned slave according to the scholars, but the scholars disputed (his status) among themselves if he was from the Arabs - whether he must be enslaved or not because when A'isha (Muhammad's wife) had a maid-slave who was an Arab, Muhammad said to A'isha, `Set this maid free because she is from the children of Ishmael.'"
In the Hadith, Muhammad called Blacks "raisin heads":
"...[Thou shalt kill an] Ethiopian (black) slave whose head looks like a raisin [should he disobey]" Sahih Bukhari 9:89:256
"the most hated among the creation of Allah is the black man" Sahih Muslim 5:2334
I heard the Apostle say: ‘Whoever wants to see Satan should look at...a black man!' Ishaq 243
Also in the Hadith is the command to enslave people of African descent. This is the correlation to the Christian idea of the so-called Hamtic Curse and no surprise, the African slave trade was completely run by a handful of rich Muslims and their Christian counterparts.
It is your folly to fight the Apostle, for Allah’s army is bound to disgrace you. We brought them to the pit. Hell was their meeting place. We collected them there, black slaves, men of no descent.
Ishaq 450