Muhammad,
Every creature I'm familiar with, including humans, prefer the yolk to the white, though I've observed some monkeys, dogs and humans (including myself) also eating the whites, including raw. So yolks are generally preferred, but raw wild egg whites are not always discarded. At least, that's what I've found in my searchings on the subject.
Thanks for the info, aLptHW4k4y and Hai!