Actually neither beer nor wine was the first fermented beverage, and wine arguably has a closer connection to health, but recent evidence indicates that humans developed the ability to metabolize alcohol long before we were even human. The uniquely human ability to handle alcohol comes from the digestive enzyme alcohol dehydrogenase, or ADH4. A new science called paleogenetics identifies the emergence of the modern version of the ADH4 gene in our ape ancestors some 10 million years ago. Interestingly, this corresponds to the time when our arboreal forebears transitioned to a nomadic lifestyle on the ground. We went from swinging from tree limbs to walking upright, and the rest is history. Understanding the circumstances that led to perpetuation of the ADH4 mutation may contain clues to what made us human in the first place.
How the ability to metabolize alcohol made us human
Paleogenetecist Matthew Carrigan has an idea about how this happened. Arboreal species rely on fruit that is in the tree, but if you can digest fruit that has fallen, and partially rotted – meaning fermented and therefore alcoholic – then you could get by just fine with less effort or when other sources of food were scarce. One simple mutation was all that was needed to impart this enhanced ability to metabolize alcohol, and this characteristic remains a defining difference between humans and other primates.
One argument in favor of the wine first theory is that wild grapes, which grew on vines climbing trees (not the neatly trellised rows in modern vineyards), simply had to be gathered. Since wine could easily come from fermented fallen fruit, it could possibly go back millions of years, requiring only the ability to collect and store liquids. Fermentation happened automatically, so winemaking was more of a discovery than an invention. Physical evidence for early winemaking includes pottery fragments with wine residue that have been carbon dated to around 7400 years ago.
There is no direct evidence for beer making until at least 1000 years later. However, it has been theorized that a taste for fermented grain products may have prompted humans to begin farming around 10,000 years ago, because harvesting wild grains in sufficient quantities for brewing would be much less efficient than gathering fruit. No hard evidence to support that idea has appeared, so the debate remains an open question.
About the only thing that we can be certain of is that the gathering of minds around shared drinks would lead to spirited discussions for millennia.