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.

Sisters have ways of socializing brothers into the mysteries of girls. Brothers have ways of socializing sisters into the puzzle that is boys.

As with real reading, the ability to comprehend subtlety and complexity comes only with time and a lot of experience. If you don't adequately acquire those skills, moving out into the real world of real people can actually become quite scary.

Science has yet to isolate the Godiva Chocolate or Prada gene, but that doesn't mean your weakness for pricey swag isn't woven into your DNA. According to a new study of identical twins, it's less TV ads or Labor Day sales that make you buy the things you do than the tastes and temperaments that are already part of you at birth.

There are a lot of ways to make people not like you, but one of the most powerful - if least fair - is to be really, really successful. Nobody resents the guy who just lost his job. But the guy whose Internet start-up made him a billionaire at 25? That's a whole different kettle of envy.

Paul McCartney had a baby when he was 61; Rod Stewart was 66; Rupert Murdoch was a stunning 72. Not only does that mean they'll have less stamina than the average dad, that means they'll, well, check out a lot sooner too.

When we're awake, cortisol can fragment memories - one reason eyewitness crime scene accounts are so unreliable. But at night that very fragmentation allows creative recombinations of ideas.