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

We are all born with an innate understanding of interpersonal equity - the idea that if you lend me your rake today, I'll respond in kind when you come to borrow my shovel tomorrow. Or nearly all of us are born with that. Psychopaths aren't.

Every batch of sperm represents an opportunity for genetic typos - called de novo mutations - to be passed on. A 20-year-old man and woman will each pass on about 20 de novo mutations to a baby they conceive. By the time the couple is 40, a woman's total has remained at 20, while a man's has jumped to 65 - and it keeps climbing from there.

We're learning how important it is both to preserve sibling relationships if they work and repair them if they're broken. We're also learning a lot about nonliteral siblings - stepsiblings, half-siblings - and the surprising power they can have.

The brain sits snugly inside the skull, but it's not a completely flush fit - there is still a layer of fluid between bone and soft tissue that serves as a natural shock absorber. Some shocks, however, can't be absorbed, and when the head gets clobbered too hard, the brain can twist or torque or rattle around inside its skeletal casing.

As MBA professors endlessly tell their students, companies do best when they stick to what they do well. There's a reason Apple doesn't make blenders. There's a reason Haagen-Dazs doesn't sell meat. And there's a reason drug companies should focus on saving and improving lives - not jeopardizing them.

Never mind what you've heard. Halle Berry was not the first black woman to win an Academy Award for Best Actress. She was actually the 74th white one. And never mind all this talk about America electing its first black President; Barack Obama is actually the 44th white man to hold the job.