What about our silly low-browed cousins the Neanderthals, can we possibly learn from them too? I think so! They were giant, strong, and smart. Their downfall, however, is that they didn't last. Could have been their harsh living environments, or they didn't catch on quick enough with advanced tools. Either way, they were more muscular than modern humans and had a significantly bigger brain.
Their diet consisted mostly of meat, but a recent article states that they ate their veggies too. It got me thinking, what fruits and vegetables were even around during this time? Did they even have the luxury to taste the sweetness of an apple or did they get their fiber from digging up stale roots? In the article, it says that on plaque found on a tooth they detected plant materials so it can be confirmed that big game wasn't the only thing on the menu.
The Paleo Diet is hard as is but The Neader Diet (patent pending, ha!) was truly grueling. Meat meat meat, all day long with the occasional plant. Not only that, they had to hunt in extreme cold and find plants that weren't exactly pre-packaged and in abundance. Could this be why they didn't last? Not enough options? What about another extreme. Meat only. Ok, now I'm just pushing the boundaries.