Quote: (02-26-2014 12:22 AM)speakeasy Wrote:
She's half black? I'd never have known. People tend to think that any time there's a mixed black and white kid the kid will look more black, but that isn't always the case. And probably a lot less than we think. There are probably tons of Jennifer Beals and Derik Jeters who we assume are white but are actually half and half.
What makes it really complicated in the USA is the history of racial mixing within the black population. The average African-American is more than a fifth European by blood (up to a quarter by some estimates). That shared heritage means that when African-Americans mix with Europeans, the appearance of the children can vary widely. They're carrying European DNA that often contains a lot of recessive European traits, and those can surprisingly show up in the children.
This also means that the kids are not quite half-and-half in many cases. Take this guy for example:
The mother and father are to the right. She's probably 100% northwestern European - very low chance of any significant non-European admixture.
He looks like what many would consider "pure black". But look at their kids:
Naturally light eye color and blonde hair, both recessive traits. How did that happen? The "pure black" dad is actually mixed - he's got multiple European ancestors, and is well under 100% west african by blood. Like many other African Americans, these Europeans are probably not much more than 4 or 5 generations back and can probably be found on both sides of his family tree.
Since he's not 100% west african (probably more like 65-75% if I had to guess), his daughter is actually not half and half. The majority of her heritage is actually European.
The products of these unions can vary significantly in appearance depending on which ones pick up recessive traits:
This is the girl above's full sister. She doesn't express any of her mother's recessive traits the way her sister does and probably looks a bit more like what you'd expect a "half and half" to look like. Like her sister, though, she's not exactly half and half - a slight majority of her heritage is probably European. Her brother, conversely, got a lot of the recessive traits too:
When you start combining highly admixed populations with largely "pure" ones, you can get a lot of unpredictable (and often racially ambiguous) results. Beals, Jeter and many others are just evidence of this.