Let’s visit our most ancient ancestors. Life was difficult for them, but they persevered and had children who
also survived and even thrived. Those children had children who had children, and so on, until our parents came along and had us.
Paleontologists and archeologists find evidence that the earliest people often lived along oceans and waterways. Water provided access to travel and trade plus an abundant source of foods. Large mounds of shells and bones demonstrated that shellfish, fish, and bird life provided ample calories. Hooks, snares, and even cultivating ponds aided them in obtaining good sources of protein.
As tribes began moving inland and exploring other continents, they continued to eat freshwater fish and birds, but they also added mammals and reptiles to their diet. As they traveled further inland, they also added berries, fruits, grasses, and vegetables to their diets. The problem with these new foods is that they were only available for short periods of time. Animals, on the other hand, were still around in the winter.
Small tribes of humans traversed the countryside, following game trails. Their instruments were crude, and not very efficient. The bow and arrow would not be invented for a millennia, so they were stuck with spears and stones strapped onto crooked sticks. The best way to kill the large beasts was to drive them through narrow valleys where the men could descend upon them with their spears and clubs. After the battle was over, and the wounded beast lay bleeding out, the men quickly dressed the animal. Their knives were crudely sharpened rocks. But with so many men working quickly, the job was done before the meat was ruined.
And then came the struggle to get the carcass back to camp. The packs they carried from the hunt were filled with bleeding and oozing meat as the trek began. And it was a dangerous trek because other animals wanted the meat the men had so heroically claimed. A bear, for instance, or even another tribe, would find it easier to steal the newly slaughtered meat than to hunt some of their own.
During the hunt, the women had been waiting anxiously for the men. They didn’t know when the men would be back, and they had to worry about keeping the children fed and occupied. The women gathered their children and went in search of food that was easily obtained. Maybe berries, maybe small animals, or they’d make due with whatever food they had stored, like dried meat, or maybe some ground and dried tree nuts.
They were concerned that their meager supply of food might not last until the hunters returned. The survival of the tribe was dependent on the nursing mothers having enough food to be able to produce adequate milk for the babies who would form the next generation for the tribe. This meant that their bodies had to have a way of storing energy as fat for the potentially long periods of time when food was scarce. And the more stress they faced, the more fat they needed to store in their bodies.
Finally, assuming that the men made it back to camp without incident, they would then hand over the preparation duties to the women who quickly began dressing and cooking the meat. The men, for their part, would lounge, waiting while wonderful aromas filled the settlement. Their bodies knew they were about to have an amazing feast.
When the food was ready, the entire tribe set to work eating as much as their stomachs could hold. Without refrigerators, our hunter ancestors had literally only days to consume the food that the hunt had provided. You ate everything. Perhaps this is where the saying came from, “clean your plate” or perhaps it was a thin flat rock dish.
The environment posed other risks in addition to not having enough food. The men faced danger from the hunt and from being hunted. Injuries were common, and these injuries often led to death. Life could be short. So their genes had to pass quickly to the next generation if their DNA was to survive. Those who stored fat better, and used it more efficiently, would survive longer and have more children than their less efficient neighbors. The women also risked being lost in their forays to find food. Their young children could not survive on their own. The very young depended on their mothers’ milk. This meant that those mothers who stored fat the best, and who processed calories efficiently, were better able to feed their family, raise healthier children, and ultimately be able to have more children. In other words, their ability to pass along their DNA was predicated on how well they stored fat.
How does all this relate to you? When you’re struggling to lose those last 15 or 50 pounds, think of your hunter-gatherer ancestors and thank them for surviving long enough to pass their genes along to you. You might not appreciate their gift of genetics right now, but it was what kept the human species on the planet. Now it will be our job to understand how to take these “survival genes” and accommodate them in our modern environment of relative safety and plentiful food.