"To be 50% German, doesn't that require one of your parents to be German, rather than having some German ancestors? "
Not in America! Let's see, your parents are 1/2, and your grandparents are 1/8, and their parents are 1/16, and their parents are 1/32 and their parents are 1/64, and at least one of them is Indian because everybody in America is 1/64 indian....hm...
its tricky but I think your great-great-great-grandparents led a rally, taht's 3/64ths ( less the Native American warrior) and your great great grandparents were there, that's 4/32s or 8/64ths, and the great grandparents are there that's 4/16ths or 16/64ths, and then your grandparents are 4/8ths that's 32/64ths, that's it right there...even if both your granddads and one grandmother opted to be Black and both your parents were Russian , if one grandma and all great grandparents on both sides were German that settles it, even excusing the Sioux war chief that's 35/64ths.
The core joke of Hitchhiker's Guide to the Galaxy is that of course no civilization would develop personal computers with instant remote database recovery, and then waste this technology to find good drinks.
Steve Jobs has ruined this joke.