facepalm wrote:Mindbender wrote:facepalm wrote:Sounds more like he's 1/9th black, 1/3rd brown, 5/9ths white. I don't think Jews, Syrian and Lebanese count as black.
The only way to be 1/9 something is is your had three genetic parents, at least one of which also had three genetic parents.
You are joking? Cause it is possible to be 1/9th something with just two parents. This just means that your parents and your grandparents and so forth are also multiracial.
It is not possible to be one ninth anything in a system where all babies genetically 1/2 of each of two parents. This is simple math. One generation up, you have two parents (each providing 1/2 of their genetic material). Two generations up you have four grandparents (each providing 1/4 of their genetic material). Three generations, eight great-grandparents, 1/8 each. The number of contributors to your genome is derived by the # of sexual genetic providers to the power of however many generations up you go. If you always have 2 parents, the only denominators you can have follow the pattern of 2^x where x is a positive integer. You can be any number of halves, quarters, eighths, sixteenths, thirty-seconds, sixty-fourths, one-hundred-twenty-eighths...etc, so long as the numerator is not greater than the denominator. You cannot be one ninth something, or two thirteenths something.
In certain plant and insect and fish species, you can get viable polyploidy offspring, where one parent provides a double (or more) dose of a set of chromosomes. Instead of two sets of chromosomes, they can have three or four or even more. This could allow non-2^x denominators, but in humans, basically all cases of polyploidy are unviable; most lead to miscarriage, and few die shortly after birth. In the rare case of mixoploidy, you don't even have a single genome to identify.