Part-black generally means all-black in Americans' minds. Just as part-Asian or part-Hispanic or part-anything-else usually puts individuals in those minority-groups' camps.

Spare a thought for the poor introverts among us. In a world of party animals and glad-handers, they're the ones who stand by the punch bowl. In a world of mixers and pub crawls, they prefer to stay home with a book. Everywhere around them, cell phones ring and e-mails chime and they just want a little quiet.

Jellyfish serve as a model for bioengineers for the same reason yeast were once so valuable to geneticists: they're simple to deconstruct.

The families of many athletes - incensed at the sports leagues and hoping to make games safer overall - are increasingly making the brains of players who die prematurely and suspiciously available for study. Some athletes are even making the bequest themselves.

A child gets vaccinated and soon after, autism symptoms emerge. The apparent cause-and-effect is understandable but erroneous - more a coincidence of the calendar and childhood developmental stages than anything else, as repeated and exhaustive studies have shown.

My family went through divorces and remarriages and the later, blended home - and then watched that home explode, too.

Older siblings get more total-immersion mentoring with their parents before younger siblings come along. As a result, they get an IQ and linguistic advantage because they are the exclusive focus of their parents' attention.