Today is D.L. Hammons's Deja Vu blogfest, when we were invited to repost something we wish had gotten a little more attention. Swing by DL's blog Cruising Altitude to check out the other participants. (And if you want to know why the possessive of D.L.'s name looks like this, check out THIS POST to get up to speed about creating singular possessives correctly.)
My repost, "Gene pool: fun with secondary characters" went up in August 2010, arguably a bad time of year for garnering comments, when everyone is on vacation.
Creating a fully realized cast of characters is for me one of the most fun aspects of writing. Part of what makes fictional characters seem real is their webs of relationships--including relatives.
Unless your main character is adopted, she will share certain characteristics with other members of the family. And this is where some of the fun comes in. As Bill Cosby joked in a comedy sketch, having children is like conducting a chemistry experiment--you mix a little of each parent and see what you get. Some kids are strongly like one parent, while others are an amalgam.
Now imagine working backwards. You have a main character. What do his parents look like? Is he a younger version of his dad? A male version of his mother? Or have the sets of genes combined in an interesting way? The genetic combo is, of course, the most fun to extrapolate ancestors for.
One thing to keep in mind when dreaming up your character's genetic heritage: you need a grasp of heredity basics (remember high school bio?). Certain traits are dominant and will most frequently reappear in offspring. Others are recessive and won't appear at all unless someone in the line has the trait. Tone deafness, for example, is a dominant trait. Your piano prodigy character must have ancestors who can carry a tune (a recessive trait).
Here's a good refresher on the basic science of heredity.
And here's a list of traits (and also here) known to be dominant and recessive.
How might heredity shape your character building? Have any characters you might alter to make your protagonist more plausible?