What makes spinal-cord injuries as devastating as they are is that everything about them plays out in absolutes: they are instantaneous, utterly disabling and horribly permanent.

Spending $1 for a brand new house would feel very, very good. Spending $1,000 for a ham sandwich would feel very, very bad. Spending $19,000 for a small family car would feel, well, more or less right. But as with physical pain, fiscal pain can depend on the individual, and everyone has a different threshold.

Habitual texters may not only cheat their existing relationships, they can also limit their ability to form future ones since they don't get to practice the art of interpreting nonverbal visual cues.

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.

Certainly, people can get along without siblings. Single children do, and there are people who have irreparably estranged relationships with their siblings who live full and satisfying lives, but to have siblings and not make the most of that resource is squandering one of the greatest interpersonal resources you'll ever have.

I was born in the U.S., my wife was born in Mexico and emigrated here when she was in college, and my daughters were born in New York City. That makes them passport-carrying, natural-born, eligible-to-run-for-president Americans. But they're also Mexicans and they like that just fine.