Narcissism is actually a clever guise adopted to mask its exact opposite, which is a deep well of self-loathing, a well of low self-esteem, rather than high self-esteem. This helps explain why narcissists are so sensitive to criticism, why narcissists tend to break into outrage if they're criticized, because their self-esteem is actually much more brittle than it seems, and once they're challenged, that mask falls apart.

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.

Introverts listen better, they assess risks more carefully, they can be wiser managers. It's not for nothing that the Silicon Valley billionaires are so often the retiring types.

The golden child may be the oldest one, unless it's the youngest. It may be the toughest one, unless it's the most sensitive. It's not even necessary that Mom and Dad have the same favorite - and typically they don't.

There are a lot of downsides to being male. We age faster and die younger. But give us this: we're lifetime baby-making machines. Women's reproductive abilities start to wane when they're as young as 35. Men? We're good to go pretty much till we're dead.

Scarily, football helmets, which do a fine job of protecting against scalp laceration and skull fracture, do little to prevent concussions and may even exacerbate them, since even as the brain is rattling around inside the skull, the head is rattling around inside the helmet.

Marketers have long known that a name can make all the difference when you're trying to move the merch. The kiwifruit was once the Chinese gooseberry, after all - at least until the produce peddlers wised up - and the Chilean sea bass was once the singularly unappetizing Patagonian toothfish.