It seems they have same meaning but I think it doesn't.
I have images that tribe is small and closer group and race is big and broad.
Tribe means a social group of people who has same customs, language.So we live in same community and shere same culture, japanese could be tribe.
Race means one of groups human can be devided into according to the color of skin etc..
So Japanese and Mongolian are same race but not same tribe.
Now it is not good that we judge people by color of skin or other physical feature,but this case, race doesn't mean such discrimination just show classification of human biologicaly.
This is just my opinion!
By the way, I'm reading a book"Wuthering Height" for my book report now!
When I read it for the first time, I did not understand what happend and was going on in the story..because it is really difficult to get the story and relation of characters are very complex!
But the longer I read it, the more interesting it gets!
I will finish reading it very sooon:)