Turns out, after all these millennia, Mother Nature is still the most functional shoe. Shoes prevent our necessary contact with the ground and modify our body posture.
Science took a long time to recognize his work.
In a new study, published in the journal Nature this week, an international team of researchers found that a well-experienced foot (that is, callous) gives us better protection than shoes. In fact, they suggest, shoes have really numbed our feet, while also changing the way we walk. And over time, that has dramatically altered the human gait.
"I'm not saying that people shouldn't wear shoes," Harvard professor and study co-author Daniel E. Lieberman tells Scientific American in a published article. Instead, it suggests that more research is needed on how footwear has altered our bodies and habits, and perhaps what we gave up on when we started covering our feet.
Like corns. For their study, Lieberman and his colleagues spent a lot of time looking at calluses, those hardened knots of keratin that form on the feet that are frequently exposed to the raw elements. In all, they examined 100 adults, mostly from Kenya, with nearly half of the participants avoiding footwear most of the time.
They found that barefoot walkers, despite thick calluses, could feel the ground a lot under their feet. In fact, even the thickest corns did not dampen tactile sensitivity. But unsurprisingly, wrap your feet in rubber and plastic and tie them with shoelaces if you did.
It turns out something as thick as corns, they still feel the ground and transmit information to the brain. The shoes, not so much. That could be a major problem for people, especially older people, who have trouble balancing, often resulting in serious injury.
As we age, we lose sensation in our feet, and a life lived in shoes could exacerbate the problem.
"If your feet can't feel what's going on on the ground, maybe you're more susceptible and more vulnerable [to falls], and shoes can be part of that," Lieberman explains. "If we can give people's brains more information, that could help them."
How do we get the nerves that run from the foot to the brain, called afferents, to keep the lines of communication open? Get a little closer to the ground. Embrace the corn.
"We suggest that children walk barefoot on wet grass in order to stimulate afferents for developmental reasons," study co-author Thomas Milani of Germany's Chemnitz University of Technology told LiveScience.
But again, that doesn't suggest that we clean our shoe cabinets. The world has changed in the last 200,000 years of human history.
Simple shoes, like sandals and loafers, may have arrived on the scene some 40,000 years ago. More sophisticated footwear, like this 5,500-year-old leather shoe, appeared much later.
And those legendary air-cushioned icons known as Nike Air? They date back to 1979 AD.
Just as the earth sculpted human feet for so many tens of thousands of years, so too modern footwear has changed us. The researchers found that all that softness and isolation makes the impact of each step disappear. We just feel it less because the energy is transferred to the joints higher up the leg. As a result, we are likely to walk very differently than our ancestors did without shoes.
Then there's the thorny issue of protecting our cute soles from the dangers of urban sidewalks. And snow, ice, and slush probably feel how you imagine they would, but you would never dare to try.
According to the researchers, the nut-like corns would have offered protection to ancient humans. No foot exposed to this world remains pink and innocent for long. Instead, knots of tough keratin are formed to cushion and protect those plants.
But let's face it, if you're going to step on a Lego brick, you'll want to have your shoes on.
Furthermore, a completely shoe-free existence poses its own problems in the modern world.
Like starvation. How many supermarkets and restaurants will deny you entry citing a strict “no shirts, shoes, and toilets” policy?
You can also die of loneliness. It won't be easy to find a partner who shares your passion for exposed feet, much less someone who appreciates the scent of a pair of feet.
Better to find the right balance between covering those feet for civil society and taking every opportunity to free them. Like on a sunny summer day, in a grassy park when you can almost hear your feet chatting happily to the ground beneath them.
They, after all, have a lot to catch up on.