Every morning in Africa, a gazelle wakes up, it knows it must outrun the fastest lion or it will be killed. Every morning in Africa, a lion wakes up. It knows it must run faster than the slowest gazelle, or it will starve. It doesn't matter whether you're the lion or a gazelle-when the sun comes up, you'd better be running.

But you can't muscle through a five-hour run that way; you have to relax into it like easing your body into a hot bath, until it no longer resists the shock and begins to enjoy it.

The only way to truly conquer something, as every great philosopher and geneticist will tell you, is to love it.

He was onto something. Something huge. It wasn't just how to run; it was how to live, the essence of who we are as a species and what we're meant to be.

Distance running was revered because it was indispensable; it was the way we survived and thrived and spread across the planet. You ran to eat and to avoid being eaten; you ran to find a mate and impress her, and with her you ran off to start a new life together. You had to love running, or you wouldn't live to love anything else. And like everything else we love-everything we sentimentally call our 'passions' and 'desires'-it's really an encoded ancestral necessity. We were born to run; we were born because we run.

-The reason we race isn't so much to beat each other but to be with each other. -The Hopis consider running a form of prayer; they offer every step as a sacrifice to a loved one, and in return ask the Great Spirit to match their strength with some of his own.

Even Charles Darwin, that human decoder ring of bizarre behavior, found the idea of saving a stranger's life to be a total head-scratcher.