First off your concept of God is WAY too limited if you're asking this question. You should ask if Adam was a brother.
Biblically, Man was made in their image: Genesis 1:26 (King James Bible):
"And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth and over every creeping thing that creepeth upon the earth."
It's not clear way the use of plural in this one verse. Some theologians suggest he was referring to the heavenly host (angels, etc) so perhaps some of them are brothers.
However, biblically Adam and Eve were four thousand years ago. Evolution of man out of Africa would have been many hundreds of thousands of years ago so the two concepts (God made man in His image, man evoled in Africa) are not compatible.
