Winter’s Bones

Betting on weather in NJ, whether days ahead or months, is a fool’s game. Nonetheless we all try regardless of our expertise or its lack. The smartest of the foolish money is on a coming winter season of heavy snow, much like last winter, in consequence of the recurrence of La Niña, a weather pattern caused by cool water temperatures in the Pacific. Whether those bets pay off or not, it won’t hurt to prepare. Having been snowbound more than once last winter with two 2WD vehicles unable to navigate my driveway much less the roads, I replaced my sedan a couple months ago with an All Wheel Drive Trailblazer. I’ve stored 20 gallons of fuel in case the heating oil delivery truck can’t make it up my driveway as happened a few times last year. I’ve tied tarps on equipment and machinery (e.g. AC and pool filter) that fare better if not infiltrated by snow. Yesterday I was up on the roof of the barn cutting back overhanging branches. Besides the risk of them doing damage by breaking, snow causes the branches to bend down onto the roof, which is not good for the shingles. I used a Sawzall and manual branch cutters for this job because I didn’t feel comfortable waving a chainsaw over my head while balancing on a roof peak.
 

With or without whirring blades, I’m cautious these days on roofs – even a one-story roof. There is a family history. My dad had a nasty encounter with a Skil saw as long ago as the 1950s when he fell through rafters. He was young and he recovered. I’m not young but I’d be averse to repeating the event even if I were. Besides, my bones probably would object to the impact from the fall alone, and not just because I’m (let’s not mince adjectives) old.

We of the 21^st century are more fragile than our ancestors, who bounced better. The further back in time one goes the greater the fragility gap. Skeletal evidence from archeological sites reveals just how much bone density has dropped. A 2017 study of remains from 5300 BCE to 100CE showed the ancient bones to be 30% stronger than those of average 21^st century people. They are stronger even than those in most modern athletes: “humeral rigidity exceeded that of living athletes for the first ~5500 years of farming.”

An interesting book on biological changes in humans over the past few tens of thousands of years is Primate Change: How the World We Made is Remaking Us by Professor Vybarr Cregan-Reid. The changes include higher rates of cardiovascular disease, smaller and more cavity-prone teeth, smaller brains, allergies, back pain, higher rates of myopia, etc. A few of the changes are genetic: brain size, for example, which is down about 10% from the peak some 30,000 years ago; this is a global phenomenon that is apparently an effect of self-domestication as human populations rose and forced more social interaction. (Domesticated animals almost universally are smaller brained than their wild counterparts.) Most of the changes are either purely environmental or epigenetic. Epigenetic influences change the way genes are expressed even though the genes themselves are unchanged. These include such things as childhood diet and exercise. Unlike purely environmental effects (e.g. adult exercise) these changes (e.g. height and foot structure) are irreversible in adulthood. They also are partly heritable, which came as a surprise to researchers a few decades ago. In general, residents of advanced countries today are weaker than our ancestors (and modern day hunter-gatherers for that matter) in almost every imaginable way. We somehow live longer anyway, but that is a testament to how safe we have made our world rather than to our innate fitness to live in it. Our sedentary lifestyle is mostly to blame. A desk job (including school) is as deleterious to health as smoking. An indication of how inactive contemporary humans are is that on average each burns fewer than 300 calories per day over the basic metabolic minimum; Paleolithic hunters (as do their remaining modern-day counterparts) burned more than 1000.
 
Based on long-term trends (especially of the last few centuries) the future of human biology is not rosy. We are not realistically about to give up the creature comforts that make us weak. However, other interventions are possible. There exist today drugs that mimic the effects on the body of rigorous daily exercise with all its benefits; they are not approved for use (the side effects are undetermined) but they might one day be on drug store shelves. Then there is the prospect of bioengineering (long promised but little delivered) that might put us into shape without medication and despite our laziness. If we do tinker with the genome, I suggest aiming (among other things) for a greater capacity to self-regulate body temperature so we can stay warm in the cold. We then could face the winter with less trepidation and lower heating bills – though higher food bills. I don’t mind eating an extra meal. Oh, yes: we should re-toughen those bones, too, to improve our bounce.
 

Guttermouth – Primate Camp