Each year, Facebook billionaire Mark Zuckerberg has a resolution that he takes very seriously. One year, he learned Mandarin Chinese. Another year, he wore a tie every day. He said the goals help him learn about the world, expand his interests, and teach himself greater discipline.

In 2011, his goal is to eat only animals he physically kills himself. This goal was first shared through a note he posted to his friends on his private Facebook page. He subsequently emailed Fortune to further explain this decision.

He said his motivation is to be thankful for what he has, starting with the meat he ate.

He said it all started when he roasted a pig at his house last year and people told him that although they liked eating pork, they don't want to think about the once-living pig.

That just seemed irresponsible to me, wrote Zuckerberg. So he embarked on his eat-only-what-he-kills journey in 2011.

So far, his kills include boiling a lobster and cutting the throat of a goat. Next, he wants to go hunting.

Zuckerberg may be part of a broader movement to step back from America's pervasive commercialism and return to more natural ways.

This goes beyond simple things like eating organic food, as Zuckerberg demonstrated.

A hot trend in the hunting community, for example, has been eschewing high-tech weapons and reverting to primitive tools like hand-made stone tip arrows.

The cutting edge paleo diet seeks to imitate the 'caveman' raw food diet of the Paleolithic era, which predates man's adoption of agriculture.

Trader philosopher Nassim Taleb, meanwhile, tries to imitate the entire hunter-gatherer lifestyle. He claims to imitate their feast and fasting eating habits and their physical routine of hunting, which consists of long periods of rest interspersed with short periods of extreme exertion.