Rh- means no Rhesus. Rh+ means it DOES have Rhesus. So, if Native Americans from both North and South America (excluding Blackfoot) - your words - are almost all O+, you DO, indeed, have Rhesus.
Rh- means no Rhesus. Rh+ means it DOES have Rhesus. So, if Native Americans from both North and South America (excluding Blackfoot) - your words - are almost all O+, you DO, indeed, have Rhesus.