Following the remarkable success of his best-selling hit The Primal Blueprint, evolutionary researcher Mark Sisson explores the reasons why so many of us, despite our outward successes, good health and personal accomplishments still feel depressed, lost, unfulfilled, or unsatisfied - as if something is somehow missing. Anti-depressants are now among the most prescribed (and largely unnecessary) drugs in the US, yet Sisson argues that there is an evolution-based reason we often feel depressed, anxious or "disconnected" from the world, from our families, our jobs or our friends. Our brains are genetically hard-wired to expect certain social behaviors and lifestyles, many of which have become adulterated or eliminated by modern civilization and technology. When we don't give our genes the signals they expect, those genes can often cause short-term bio-chemical depression, anxiety, unrest or sadness. The path to happiness, success, satisfaction and fulfillment lies in adopting the simple lifestyle strategies Sisson outlines here. "Reconnect" with your Primal genes and experience a renewed sense of completeness, satisfaction and contentment.