In A Nutshell
Generally, we think of the development of agriculture as a good thing. But recent research shows that with the lifestyle changes that came along with farming and the dietary changes made when we became less dependent on meat, we started to devolve. Our jaws became smaller but our teeth didn’t, leading to the dental problems that many suffer from today. Our skeletons became less dense and more easily breakable, and our joints became weaker.
The Whole Bushel
The switch from a society of hunter-gatherers to one largely based in agricultural has long been considered one of the great turning points in humanity’s history. It’s often credited with getting us to the point we’re at now, but researchers have been taking a closer look at the effects on the human body as we’ve made the switch from a diet and lifestyle of hunters to one of farmers.
If you’ve ever gone to the dentist and gotten bad news of any kind, you can most likely thank our early agricultural ancestors. According to work done by the Israel Antiquity Authority, University College Dublin, and the State University of New York at Buffalo, about 12,000 years ago our teeth and jaws took a turn for the worse. The study looked at a huge amount of data, studying almost 300 remains dating from 28,000 years ago to 6,000 years ago. Those teeth and jawbones that belonged to members of a hunter-gatherer society fit almost perfectly together. Once society shifted to a more agricultural setting, the lower jaw changed shape and size, resulting in the common conditions of dental crowding and malocclusion that we suffer from today.
The shift comes with a change in diet, it’s thought. A hunter-gatherer diet was heavy in meats and raw vegetables, which made for some heavy chewing. When the diet became more based in cooked foods and things like grains, our bodies adjusted the size of our jaws. We still needed our teeth, though, and they didn’t undergo a corresponding shrink.
Our bones were changing, too. Around the same time we started farming—around 12,000 years ago—our skeletons started adapted to a more stationary lifestyle. Bones became lighter and longer, and in the process, they became more breakable, too.
It’s not just our bones that suffered. According to a study co-authored by Habiba Chirchir of the Smithsonian’s Human Origins Program, agriculture changed some of the most fundamental structures of the human body. When they looked at the makeup of trabecular bone, they found some major changes. Trabecular bone is the mesh-like substance at the ends of bones that helps form joints. Compared to our hunter-gatherer ancestors, our joints are considerably weaker. Compared to our closest primate relatives, we’re even farther behind. The primates studied had anywhere up to 75 percent denser structures making up their trabecular bones, while our ancestors’ bones were around twice as dense.
Thinking that a change in lifestyle was a likely reason for the shift from heavy, strong bones and powerful joints to less durable skeletons, they looked further. They compared a few sets of ancient bones, some from a farming community and some that lived a foraging lifestyle. They found that there was a bigger difference between groups based on lifestyle rather than diet, painting a fascinating picture of just how such a drastic shift in lifestyle can impact the evolution of an entire species.
And that held up when they looked at full skeletons, too. When agriculture first became a major life choice for people, the results were biologically devastating. Not only did we suffer deaths on the same scale as a major plague, but the population on average became shorter and less healthy. They were more susceptible to disease and illness, made worse in large part by the close proximity people were living in, all without access to modern sanitation.
Today, there’s increased concern about our even more sedentary lifestyles, with many of us making a living confined to offices and tied to our desks. We may have been going down the road of a more brittle skeleton for centuries, and with cases of osteoporosis higher than ever, it’s an intriguing look at the long-term damage that lifestyle and diet can do.
Show Me The Proof
Phys.org: Malocclusion and dental crowding arose 12,000 years ago with earliest farmers
Smithsonian: Switching to Farming Made Human Joint Bones Lighter
Science Daily: Dawn of agriculture took toll on health