Some very obvious physical features get passed down generation after generation. That's why when you look at family photos, you can see that you might have your aunt's eyebrows, your grandpa's nose, your great-uncle's elbows, or your greatgreatgreatgrandpa's charming smile.

Traits that get passed on nearly every generation (or resurface after skipping a generation or two) mean that they are most likely linked to dominant alleles, as opposed to recessive ones. An example of a dominant allele would be a widow's peak. So if you're worried about having one in the future, have a look at your family tree to spot where you're most likely headed.