Spencer, Razib and guest Gareth Highnam take you "behind the scenes" of your holiday meal. A whirlwind tour of 10,000 years of history, you'll discover how and why your genome plays a role in metabolizing what you eat and drink during the festive season.

Around 10,000 years ago, a few human communities around the world made a momentous decision: to stop hunting and gathering, and become farmers. Why did this shift in lifestyle happen, and what unexpected effects did it have on our ancestors - and us? The answers can be found in Middle Eastern archaeological sites, carefully measured skeletons, a bit of botanical sleuthing...and in our own DNA.