Is academic achievement commonly associated with Asian students really based on immigration?

Or perhaps that the nature of immigration selects some national origins differently from others. In 2000 (see http://www.migrationpolicy.org/article/educational-attainment-foreign-born-united-states ):



Origin          % HS+           % BA/BS+        % MA/MS/PhD/professional

China           70%             42%             24%
India           89%             70%             38%
Mexico          30%              4%              2%
Philippines     87%             45%              8%
Vietnam         61%             20%              5%
Non-immigrant   83%             24%              9%


Is it a surprise that kids of immigrants from China and India who commonly have high levels of educational attainment tend to do well in school, whether you see nature or nurture?