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Reading List More from Luxagraf: Topographical Writings
We swing south to Albuquerque, catching I-40 west for a few miles. The earth turns redder, with a thin frosting of green -- junipers, snakeweed, and shrubs on the mesa tops. The sky is impossibly blue, littered with tufts of white cloud. Just before the city the oil pressure gauge unaccountably drops. If the 1995 F-350 has a weakness it's the gauges, which are notorious for giving faulty information. Hooking up a better engine monitoring system is high on my list of things to do, but there was no time before this trip. I contemplate stopping at a diesel shop in Albuquerque, but decide against it when the gauge seems to return to normal. Probably a bad gauge. We ditch the interstate as soon as we get through Albuquerque. On the map last night we found a thin black line, a remote looking road, just after the Acoma Pueblo, that weaves its way across the desert and up into the mountains around Show Low. We thought we'd give it a shot and see where it goes. We're the only vehicle that gets off I-40 at this exit, which is an encouraging sign. The road quickly turns to a narrow two lane strip of blacktop, meandering west, through the grasslands and scrub, toward a large escarpment of sandstone. We're too early to see the grass green. Most of the water here comes when the monsoon rolls through in July and August. Right now the land is at it's driest, the grass brittle and brown, and all but the biggest Tinajas are mere sandy holes in the rock. Only the Ponderosas, Pinyons, and junipers dotting the hills are green this time of year. When we reach the sandstone bluff the road turns to follow the base of it westward. Off to the right rivers of black rock flow down the side the hills and into the small valley. It looks more like Hawaii than New Mexico. The dark lava flows are almost as recent as they look, several are only a few thousand years old. The Zuni in the nearby Acuena pueblo have been here long enough to have stories of when the lava flowed. Part of the reason the Zuni live in this area is that when they first arrived there were lava caves, which made good shelters and held water, always the most difficult thing to find in this land. We're skirting the edge of the El Malpais National Conservation Area, home to La Ventana, one of the bigger arches in the southwest. Given more time we'd have stopped to spend some time here. There's a campground we could have stayed at and at night hundreds of thousands of bats fly out of some of the lava tubes in the area, but we're on a tight schedule unfortunately, and need to be in Tucson in two days. We have to get by with seeing the arch from the parking lot, and saving the bats for another trip. There's always something you have to save for the next time. And more than seeing, this is a trip of long distance driving. Eventually the sandstone bluff drops away and it's wide open high desert grassland as far as you can see. And it is good to see so far. I remember when I come out this way that whatever else I might have become, I am at heart a westerner. The endless horizon and huge open skies that give some people vertigo and all manner of uneasiness, feel natural to me. The way the world should be. The western sky is as much a part of the land as the land. The only other place that's true is on the ocean. Nothing feels quite like home to me as seeing a wide open expanse of land with the horizon so far away it's hard to see where the land ends and the sky begins. Eventually the road begins to head upward, climbing steadily toward the White Mountains. Towering Ponderosa pines become more common. We're on the south eastern edge of the Mogollon Rim, where the Colorado Plateau drops down into lower central Arizona. Tomorrow we'll trace that transition from the mountains down to the saguaros and cacti of the Sonora desert. Tonight we grab a campsite outside of Show Low and cook dinner over a fire. Surprisingly camp fires are allowed here. The west has become very skittish of fire. Decades of poor land management have left much of this land extremely vulnerable to wildfire. Throw in drought, pine bark beetles, irresponsible people and you have a recipe for devastating fires. Part of the reason we first went to the great lakes area -- which we now call home -- is that we were tired of the stress of not knowing if or when a campground out west would close. And often there was nowhere else to go when things did shut down1. The shores of Lake Superior proved a more relaxed, reliable place to spend our summers2, and so we did. But here in Show Low at least fire doesn't seem to be a concern right now. The road from Show Low to Tucson drops down out of the White Mountains and into the desert. About half way out of the mountains there's a turn off for Fort Apache. For a long time Fort Apache was the Army base from which soldiers, assisted by White Mountain Apache scouts, fought the various other Apache bands in Arizona, including Geronimo's band of Chiricahua Apache. We've seen the Chiricahua Apache's homeland in southern Arizona, and been to the prison where Geronimo was held for many years. Fort Apache felt like a missing connection, the other side of the story perhaps. The drive in is a quiet winding road through the White Mountain Apache reservation. We didn't see another car until we were in the town of Fort Apache, and we were the only people at the fort. Fort Apache is not a fort in the traditional sense of western forts. It came after the need to defend against attacks and does not have a surrounding wall. It was a staging area, what we'd call an Army base today. The historical site is managed by the White Mountain Apache tribe, who've created a little visitor center with info on the tribe's history, and a little bit of the fort's history. Several of the old fort buildings have been restored, though there's only a couple that are open to the public. The old schoolhouse is still in use, now administered by the tribe. We wandered the grounds for a while. The desert here is quiet and cool this time of year. Perhaps always. The river behind the fort area is lined with tall cottonwoods. It's a beautiful location, you can see why people would live here, but something about the place, perhaps its history, didn't make us linger. We headed back out to the highway, again seeing no other cars between Fort Apache and the main road, and turned left, bound, finally, for Tucson. Highway 66 makes a very dramatic pass through the Salt River canyon on its way south. For all our travels in the bus, this kind of rugged, steep canyon country isn't something the kids have seen a lot of because this is the sort of road that the bus just wasn't capable of driving. The truck had no such troubles, winding through the hairpin curves without a thought and climbing thousands of feet without dropping more than a gear. At the bottom of the canyon there's a very large pullout parking area, with stairs down to the river. We stopped for a bit and wandered around the river banks to take a break from driving. Back up in the parking lot, several people were standing beside overheated vehicles,and one guy was underneath his old Jeep with a litter of tools on the ground beside him. His wife and kids waited patiently in the back. The kids and I looked at each other. How many times had that been us? Too many to keep track of. I considered asking if he needed help, but overheard him tell someone else he had it under control. I never wanted help either. After the canyon of the Salt river the road wandered through the high desert, down to Globe where we took a left and continued our descent down into the desert, until pretty soon the hills were dotted with Saguaros and we were on the outskirts of Tucson. Even when fires don't threaten campgrounds directly, they are often shut down to use as staging areas for fire crews. ↩ Our area does get its share smoke from fires in Canada and the Boundary Waters, but so far no actual fires have threatened anything around us. ↩
My daughters have been grappling (both in juijitsu and wrestling) since they were eight years old. This winter marks almost six years of training (with some gaps when we were on the road). In all that time they've never really tested themselves in any formal way. They've wrestled in a handful of small, local competitions, but that's it. As a parent it's always hard to judge your children's abilities—are they really good? Or am I just biased because of course I think they're really good? Impossible to say, and probably not your place anyway. All you can do is encourage them. But when the girls got the chance to wrestle at the Wisconsin youth state wrestling tournament, they didn't need any encouragement, they both jumped on it. The nearest qualifying matches were about four hours away. Since we couldn't both go to the qualifying match and states, Corrinne and I decided to split it up. She took them down to the qualifier and if they made it I'd take them to states. I did not see their qualifying matches in person, though I did get to see the videos later. Lilah wrestled what both her coach and her most experienced teammate called a perfect match, which is the grappling equivalent of pitching a perfect game. Alas, just as in baseball, pitching a perfect game does not get you to the World Series. Despite that win, she was eliminated in a later bracket and did not make it to the state championships. Olivia was undefeated at the qualifier and not only made it to states, but got a first round by. Two weeks later, on the morning of a late winter snow storm, the kids and I headed down to Madison for the Wisconsin Youth State Championship. The girls portion of the tournament was on Sunday, but we drove down on Friday to catch some of the Saturday matches so they could cheer on their teammates. This left us with a good bit of time to explore Madison. We broke down here once in the bus, but other than that quick pass thru, we'd never been. The truth is we're not really city people anymore, but since we were downtown we walked around and stopped in at the state capital building. I don't really think of us as living in Wisconsin. Where we are feels totally detached from the rest of the world. But when in Rome, go to the Vatican I guess. The capital building was an interesting reminder of how making beautiful things used to be a cultural priority. Even the elevator doors weren't just elevator doors. I wasn't quite sure how states would go for Olivia. At her age finding the delicate balance between self-confidence and humility -- which is a tight rope walk on the best of days -- isn't easy, and too much of either can send you spiraling into places you're better off not going. To my mind this is why sports exist though, to help you find that balance. They are fundamentally contests of will and spirit, but with a healthy side of real-world, rubber-meets-the-road physical ability you either have or are still working toward. And whenever you start to feel like you're getting somewhere in your corner of the world, the larger world is out there to remind you that it exists too, and it might well have been training harder, and for longer, than you have. This year at the Wisconsin Youth State Championships there were almost 900 girls competing. Girls youth wrestling has exploded in popularity over the past few years, which is amazing to see, but also means it's more competitive than ever. One small, focused group in the midst of a lot of chaos. Olivia ended up winning all but two of her six matches. She lost to the same girl twice, which put her in 4th place overall for her weight bracket. Considering she had only competed a handful of times in the past she was very happy with the results, and I realized it was probably the best outcome for her. She found that balance perfectly. Now she knows that she is a great wrestler, but she also knows she still has work to do to get better. One of the fun things about grappling is that no matter how good you are, you can always get better. Like her sister and the rest of her team, the minute we got home she wanted to start training again for next year's Youth State Championships. There is always next year.
I've never been much of a car driver. I had one in high school, but pretty shortly after I got a truck and never looked back. Trucks are an entirely different, and better, driving experience. You get an elevated view of the world, and the drive is more relaxed, like you're floating down the road, almost more like steering a boat than a car. At least in older trucks. From the day we bought our sticks and dirt, I've been searching for a new truck. New to me that is. I had no desire to buy an actually new truck. There hasn't been a decent vehicle made in well over a decade. Long time readers will know that I used to have a 1969 Ford F-250. Having now had a Ford and a Dodge, I thought maybe I'd get a Chevy truck to round things out. But I really want to learn my way around diesel engines, and when you start looking at diesel trucks, there's one engine that consistently rises to the top of every discussion: the Ford 7.3 Powerstroke. In particular the Powerstroke used in the Ford F-250 and F-350 from 1995-1998. As luck would have it, the crew cab version of this truck is also one of the few trucks that will comfortably fit five people and a dog. This engine is actually the smaller cousin of the engine in our school bus, the Ford Powerstroke being descended from the Navistar T444E engine, the smaller version of the engine in our schoolbus (the DT466E, also a legend among diesel enthusiasts). Finding a good condition, relatively low mileage, version of a 30-year-old truck that was only made for four years is challenging. It took me almost a year, but in the end I found what I was looking for down in Texas. Both this and the following image are from the original ad. Despite how it looks in this image, it's white and blue. This is the third time I've traveled a significant distance to buy an old vehicle. I don't consider it unusual to do so, but in talking with normal people I've parsed out that this is generally considered a strange, possibly quixotic thing to do. I never gave it much thought. I just lined up the money for the truck, booked the plane tickets, and jumped. The previous owner, who I'd talked to quite a bit on the phone, offered to pick me up at the San Antonio airport, so I flew down from Minneapolis and we drove the truck back up to Blanco, Texas where he lived. Luckily for me there's a Texas State Park right in the middle of Blanco, appropriately named Blanco State Park. I had already booked a campsite there that put me within walking distance of food, supplies, and most importantly, the bank. Blanco State Park flanks the spring-fed Blanco river, which cascades through the park in a series of small waterfalls. I'd guess about half the population of Blanco was out that evening fishing just above the start of the falls. It was a lovely warm evening with almost tropical breezes coming in ahead of a thunderstorm. I walked the river and watched the storm roll in, sweating a little in the evening heat, something I hadn't done in half a year. The storm hit just after sunset. I crawled in my tent and fell asleep to the sound of rain drops pounding on thin nylon. The next morning I got up and hiked downstream, marveling at signs of spring that wouldn't show in Wisconsin for at least another couple of months. It's strange how much something a simple as a flower can come to mean when you haven't seen one in so long. I flew down on a Sunday, figuring we'd go to the bank and start the money transfer process on Monday. Ideally I'd be on the road, back to Wisconsin, by mid week, Friday at the latest. The potential holdup is that I bank at a small credit union, which is somewhat old fashioned in the way it operates. I was worried they would not process the electronic transfer right away. But then we did something I will confess I haven't done in years. We went inside his bank and talked to an actual human being. That woman got on the phone with my bank, talked to another actual human being, and the money was in the seller's account about an hour later. Contrast that with when we bought the Jeep, where no humans were involved in the process and it took 4 days to transfer the money between accounts. Progress. The only downside to the quick turn around was that I didn't get to spend another night camping in Blanco. Instead I was on the road by early afternoon, whipping through the Texas Hill country, bound for Wisconsin. The truck ran flawlessly. That first day I never used the stereo, preferring to get to know the hum -- er, maybe more like soft roar -- of the engine. I took the back roads, avoiding Austin and other cities in a wide western arc of two lane blacktop that took me through plenty of small towns and the vast open beauty of the Texas hill country. I kept going an extra hundred miles after dark to make it out of Texas before I slept that first night. The second day I made it all the way up to middle Iowa without incident, and I was home by dinner on the third day. The Powerstroke did not disappoint. In the end it was a entirely uneventful drive, other than watching the price of diesel jump 15 cents a day. Fortunately the truck gets surprisingly good gas mileage. Despite being something of an beat up old farm truck, she's a very comfortable ride, perfect for the long road trips I have planned.
Here in the North, winter effectively begins with the first snow that doesn't melt. This year that was the day before Thanksgiving, almost exactly a month before the calendar says winter begins. It was heavy snow, over a foot, and just like that the world of color is gone. Everyone enjoys the first snow fall. It's a blanket of white that remakes the world, clean and new. The land brightens up. The white amplifies the scant daylight and the world feels brighter for a time, even as the sunrise grows ever later and sunset ever earlier. Several luxagraf readers have reached out to say that they were surprised we stayed for the winter, they'd assumed we had a snowbird lifestyle planned: stay up here in the summer and fall, and head to Florida for winter and spring. That actually is sort of what we had planned, but it hasn't worked out that way. Our kids are really into wrestling and the wrestling season, such as it is, runs roughly late November to early March, which means we stuck around for winter. It's a pretty common sentiment among those who don't live in winter that it's somehow miserable to be cold all the time. On one hand I understand that, and I feel it sometimes, but on the other hand it's not that hard to stay warm and there's something really great about lighting the bedroom wood stove on a cold morning, watching the frost on the windows melt as you warm your hands over the fire and wait for the coffee to boil. Our house has great southern exposure and good insulation, which means on sunny days in the winter we hardly need to heat it at all. The main living space is upstairs and it too had a wood stove. I would guess we lit it less than twenty five times all winter, and many times when we did we had to open the windows shortly thereafter. It's a strange thing to have to open your windows when it's 10F outside, but we have. The harder thing to do is get out in the cold. I would say the single most important things we learned in seven years on the road isn't travel-related at all, but that life was meant to be lived outdoors. We were meant to get up and go aside. I think this goes all the way back to the caves and shelters at the origin of humanity. Get up, go outside. That's how life was meant to be lived, but it's easier said than done when it's well below freezing outside. My wife is the best at this, or she was this winter. She's out walking nearly every morning. I'll admit I did not get out much. I came to prefer the warmth of the wood stove. I ended up moving my writing desk down to the coldest room of the house just so I could have more fires in the stove. But I did learn a good bit about dealing with cold. The biggest thing you need to enjoy the cold is warm feet. Solve that (I haven't quite yet) and you'll enjoy the winter much more. Next year I'd like to get some good snowshoes and maybe some cross country skis and see if I can get outside more with those. One of the nice things about winter is you can glide right through areas that are impassable when the summer undergrowth is in full swing. That opens up all kinds of things to do and see that you can't otherwise. I've been eyeing the boundary waters area for some possible winter ski trips next year.
A couple weeks after Olivia and I went to the north shore, Lilah decided she wanted to do a similar trip. The weather had turned much colder by then, reminding me why we used to head south long before now. I dug out the heavy sleeping bags and we bundled up for what was likely the last camping trip of the year. Even if we were willing to brave the snow and cold, all the campgrounds would soon be closed. It was a bright clear day, at least when we started out. The air was crisp but it was warm in the golden early morning light. We skipped Hawk Ridge and Duluth entirely this time and went straight to a pie shop, which is about the only place around Gooseberry Falls to get lunch. Betty’s Pies in Two Harbors claims to be world famous for its titular pies. I like tiny shops in out of the way places that call themselves world famous. I've always found it amusing that in many European countries you can't claim to be world famous, that would be false advertising (potentially, most likely anyway). It's funny because, well of course these places aren't world famous. Betty's is a little pie shop on the remote northern shore of Minnesota, the vast majority of the world doesn't even realize there's a state in America called Minnesota, let alone that it has a pie shop somewhere. But here in states there's no one telling you can't claim to be world famous if you want to. I guess we just have bigger grains of salt in these parts. World famous or not, Betty's was packed on a rainy, overcast day in late October. We waited 45 minutes for a table. We ended up with salads since there wasn't much else on the menu we could eat. We followed those up with some slices of pie. The pie wasn't half bad. I bet someone up the road in Canada has heard of Betty's, so world famous it is (hey, if it counts for the World Series, it counts for pies). Later we learned that the Rustic Inn Cafe apparently has better pies. Future exploration is warranted. Somewhere between salad and pie the sky clouded over and what little warmth there had been in the day disappeared. Our plan to hike around Gooseberry Falls sounded rather cold and forlorn. After debating what to do for a bit, we decided to abandon the lakeshore and drive up into the north woods. Just outside of Ely (pronounced Elee, should you ever find yourself in the area) there's a wolf sanctuary that Lilah had been wanting to visit for as long as we've been coming up here. For one reason or another we'd never made it, but after making some phone calls to ensure it was still open, we headed north. The land north of the lake quickly changes from the red iron of the shoreline area to rougher, rockier terrain with granite outcrops and boulder fields where the glaciers long ago laid down stones like a child emptying a pocket full of pebbles. This area has a more alpine feel to it, which reminded me of the Sierra Nevada. It's rugged, rough landscape that's hard to drive though -- you want to get out and explore, no matter how cold it might be. I can see why people love the boundary waters, which begins not far north of Ely. There were a disconcerting number of what looked like dying pine trees on the drive, all turned yellow. But there are a lot of dead pines around these days so I didn't think much of it at first. Then the forest became thick with these yellow trees. I'd never seen anything like it before. We stopped to check them out and realized they weren't dying, they were changing color. I'm not sure why, but a word popped in my head: Larch. I still don't know how or where I came up with Larch. Most Americans would call them Tamarack if they know of them at all, but most of us don't because they only really grow in Northern Minnesota and a few spots in the very northern Rockies and New England. There are two species in the U.S., the ones around here are Larix laricina. The striking feature of the Larch is that it's a deciduous conifer, its needles turns yellow every fall and then drop off when the first snows arrive. The wolves proved less striking than the Larch, opting to remain in their den sleeping for the duration of our visit. We still haven't seen the wolves at the wolf sanctuary. Afterward we wandered around Ely for a little while, marveling at the massive stacks of canoes in winter storage, which seem to be piled all over town. After a stop at a disappointing bookstore we decided it was time to find somewhere to camp. Car camping this time of year in these parts is challenging. Very little is open. We tried to ask at the forest service center in Ely, but it was closed for a government shutdown or something of that nature. Not having a ton of options, we set out for a campground a little ways out of town which should have still been open, according to the map anyway. Why would you close something at the end of a road like this? What is the point? Things started out promising. The road quickly turned to dirt, then to more of a double track through the woods, before finally ending at a campground on a lake. Which was closed. I considered camping their anyway. It was unlikely anyone would be checking up on the place on a Sunday night in October, and we didn't need anything more than a parking spot for the night. But in the end we decided to drive back down to Gooseberry Falls, not so much because we were worried about camping in a closed campground, but because it was supposed to be about 10-15 degrees warmer down by the lake. An hour later we were back at Lake Superior in a campsite at Gooseberry Falls. It was moderately warmer. We made a small fire and cooked some steak and potatoes. Later we sat around the fire, talking and staring up at the stars. But it wasn't long before we hit the familiar point every cold weather camper knows, where your front is warm from the fire, but your back is cold. Soon you're to shivering on one side, sweating on the other. The only real solution is to crawl in your sleeping bag and dream of summer.
More in life
[Epistemic Status: Speculative unifying theory of biology.] I don’t know about you, but I greatly resent having to be a biological organism and subject to all the poor engineering and design decisions that entails. This has many manifestations. A recent one is often wondering, why is the entire body such garbage except for the liver? Take the kidneys. Once you reach adulthood, they start to slowly decay. You can damage them through not-obviously-dangerous stuff like taking too much vitamin D or taking ibuprofen while dehydrated. Significant damage typically leads to scarring and a permanent reduction in function. Or take the gums. If you brush too hard or don’t floss enough, they may retreat down your teeth, never to return. Most of the body is like that. But the liver. My friends, the liver! If it’s injured, it will usually heal without scars. As you age, it typically maintains near full strength. You can give half of your liver to someone else and it will regrow to full size and function in a few months. I’d like to find whoever designed the liver and have them make me a full body. Except here’s a theory: It’s good that most of the body is fragile crap. It would be better if some parts of the body were more fragile. Some other ways the body would appear to be poorly designed Menopause. We’re still struggling to reconcile modernity with the short human reproductive interval. But did you know that menopause is almost unknown outside of humans? Even the other great apes remain fertile for almost their entire lives. The only known exceptions are (1) killer whales, (2) pilot whales, (3) beluga whales, (4) false killer whales, (5) narwhals, and (6) one specific population of chimpanzees in Uganda. Inuries. If your leg gets chopped off, that’s it, no more leg. Your body will try to grow scar tissue over the wound and then you’re on your own. But if you chop off the leg of a salamander it… grows a new leg. Isn’t that the obvious to do? Why don’t we do that? Telomeres. The ends of your chromosomes have a little repetitive sequence called a telomere. When cells divide, the body tries to copy the DNA, but good-old DNA polymerase can’t quite copy all the way to the end, meaning the telomeres slowly get shorter. After dividing 50-70 times, the telomeres are gone, and the cells stop dividing and then slowly stop working. This is one of the many ticking clocks of aging. Transplants. If you need a new kidney, and someone is nice enough to give you one of theirs, your body will respond by trying to kill it, meaning you have to take horrible immunosuppressants for the rest of your life. And even after taking them, there’s a 30% chance the kidney will be rejected within 10 years. This is not helpful. Diabetes. Some day, your immune system may decide to attack your pancreas. After a while, your pancreas will stop making insulin, meaning that unless you reorient your entire life around keeping your blood sugar in check, your eyes, kidneys, nerves, and heart will constantly accumulate damage. Your immune system should not attack your pancreas. Brains. After you reach adulthood, neurons don’t divide. If some of your neurons die—which happens every day—then they’re gone. If you get a brain injury, the other neurons will try to “learn around” the injury, but the neurons themselves are never replaced. Junk. All cells build up various “junk” over time. As they divide, the junk is diluted. But some cells (neurons, various cells in the eyes) never divide, so the amount of junk (e.g. lipofuscin) just goes up and up. This is another ticking clock. Blood. Your flesh needs blood, which your body delivers through blood vessels. Over time, these can get clogged with plaque. The thing to do in this situation is to sprout new blood vessels. Your body knows how to do that. But by default it maintains high levels of various inhibitors (angiostatin, endostatin, THBS1) that tell your cells not to do so. If your heart or brain get starved of blood, your body will try to reverse all this inhibition, but the process is slow and clumsy and can only produce tiny blood vessels. What’s going on here? As always in biology, the correct answer is: A lot, it’s complicated. But I think there’s a common thread. The clearest case is probably telomeres wearing down as you get older. At first glance, you might ask, why does this problem exist at all? Bacteria—because they aren’t idiots—have circular DNA, which doesn’t have ends or telomeres. Eukaryotes like us evolved from bacteria. Who decided to replace circular DNA with linear DNA? Or, you might ask, why doesn’t the body re-lengthen the telomeres? Well, actually it does! We have an enzyme designed specifically for that purpose, called telomerase. But, after embryonic development, the body doesn’t bother to use it, except in stem cells, reproductive cells, and certain parts of the immune system. Huh? The reason we have linear DNA instead of circular DNA is contested.1 But whatever. If the body wanted to re-lengthen the telomeres, it could easily do that. Your cells already have DNA to make telomerase. They just don’t use it. Instead, they let the telomeres get shorter until they stop dividing and stop working. Why? Because… … Cancer. (That’s our answer to the question in the title of this post: The human body is so crap except for the liver because cancer. As we’ll see, this answer is only semi-correct, and even then only with several caveats. But what do you expect from biology?) Letting the telomeres get shorter is not a mistake. It is a deliberate design decision.2 Often, in your body, the following happens: Some cells get a mutation that causes them to start reproducing too fast. Your immune system decides they’re suspicious and kills them. You’re fine. 👍 But sometimes this happens: Some cells get a mutation that causes them to start reproducing too fast. They grow for a while, but then (for complicated reasons3) they stop increasing in number. But they aren’t just sitting there, they’re constantly reproducing and dying, much faster than normal cells. Eventually, they develop another mutation that allows them to overcome whatever was stopping them from growing. This continues for a while, with the cells gradually acquiring more of the mutations they need to grow to a large size. But wait! With all this reproduction, at some point the mutated cells ran out of telomeres and stopped being able to reproduce. Ha! Screw you, mutated cells! 👍 To be clear, this also sometimes happen: (Steps 1-6 above) With all this reproduction, at some point the mutated cells figured out how to turn telomerase back on. This re-lengthens their telomeres, so they can reproduce indefinitely. They either stop growing for other reasons (👍) or you use our modern technological civilization to kill/remove them (👍) or they grow so slowly that something else kills you first (🤌) or there is a less desirable outcome (👎). (If you’re a biologist who is outraged at the above description, I’ve written a footnote which I beg you read before yelling at me.4) Having telomeres that wear down is good, because it slows down cancer. It’s also bad, because it means our bodies slowly stop working. Evolution decided the good outweighed the bad, and I expect that evolution was right. Several of the other ways in which the human body is “crap” can be explained in the same way. Why can’t you re-grow your leg if it gets chopped off? Well, that would require that all your cells have a “begin rapid growth mode” button on them, with some external trigger. In a sense, it would require your body to leave your cells sitting around in a state that’s closer to being cancer. Not doing that is good, because it slows down cancer, and bad, because you can’t grow a new leg. Evolution apparently doesn’t like that tradeoff, and again I assume evolution is right.5 Fragile kidneys are much the same. We could have kidneys that try harder to repair themselves. That’s probably biologically possible. But it would likely mean more kidney cancer. Arguably, the question isn’t, “Why are the kidneys such fragile crap?” but rather, “Why is the liver so weirdly regenerative?” OK, so why is the liver so weirdly regenerative? That question has two standard answers. Answer #1 is that the liver has a hard job. It sits directly downstream of the gut. If you eat toxins or bacterial products or viruses or parasites, the liver sees them at high concentrations before the rest of the body. Not only that, it’s the liver’s job to detoxify stuff, and detoxification chemistry is often self-damaging: The liver breaks toxic stuff down into even-more toxic stuff, and then deals with that stuff recursively. The liver is constantly getting damaged, as part of its job description, so it must be able to regenerate. Evolution designed it to do that, and it just pays the cancer tax. Answer #2 is that the liver isn’t unusual. Your skin can survive wounds. And your intestines can survive exposure to digestive enzymes, bile, and bacteria. The surface layers of both of these are constantly turning over. And, lo and behold, skin cancer and colorectal cancer are both very common. At the other end of the spectrum, neurons and cardiac muscle cells don’t reproduce after childhood. If they die, they’re gone.6 As a result, “heart cancer” is almost unheard of. (The very term “heart cancer” almost sounds ungrammatical.) Brain cancer is a thing, but it’s essentially always in other types of brain cells, not neurons. So maybe we can think of different parts of the body as making different tradeoffs between regeneration and cancer risk:7 Organ Regeneration Cancer risk Colon / rectum Extremely high High Bone marrow Extremely high High Skin High High Liver High High-ish Bladder High High-ish Thyroid Medium Medium? Kidneys Low Low-ish Cardiac muscle Near zero Very low Neurons Near zero Near zero At first glance, we seem to have a cute little story: Evolution pays the cancer tax for organs that need to interface with the environment, because it’s a harsh world out there. And it pays the fragility tax for organs that can be tucked away so that regeneration isn’t as necessary. Wouldn’t that be nice? Let’s formalize that as a theory. Theory: More regeneration implies more cancer risk. Evolution tunes organs that encounter the environment for more regeneration and more cancer. It turnes organs that don’t for the opposite. Of course, it’s not that simple. Complexities One problem with the above theory is that it isn’t clear that regeneration is always an option. The skin and guts are pretty homogeneous (at least in each layer). The liver can be approximated as a big blob of repeated functional units. If you give half your liver away, those functional units get larger, which is how your liver grows back to near full size and function. But other organs are highly “structured”. Your neurons are a complex circuit encoding all your memories and learned behaviors. If neurons were reproducing, that circuit might be unstable. Your heart is also highly structured. And even if your heart could re-grow, if you lost half of it, you wouldn’t survive long enough to do so. (Do not attempt to donate half your heart.) In principle, it’s surely physically possible to design a heart where you can remove half and it will still pump enough blood to keep you alive while it re-grows. But evolution either didn’t figure that out, or didn’t think it was worth the trouble. Either way, with the current heart design, high regeneration doesn’t look like an option. So it’s not as simple as evolution choosing to pay the cancer tax for some organs and choosing to pay the fragility tax for others. Some organs need to maintain a stable complex structure to keep working, meaning there may not be much of a cancer/fragility knob to turn. Revised theory: More regeneration implies more cancer risk. Evolution tunes organs that encounter the environment for more regeneration and more cancer. It turnes organs that don’t for the opposite. But for highly structured organs, regeneration might not be an option. Fine. But there are several organs I didn’t include in the above table. For example, look at this: Organ Regeneration Cancer risk Lungs Low-ish High The lungs are the worst of all possible worlds, with low regeneration and high cancer. As far as I can tell, this is a consequence of the physical fact that gas diffusion is slow. To work around that, your lungs have a delicate fractal geometry that crams ~100 square meters of surface area into a ~5 liter volume. That’s impressive, but it makes regeneration hard. At the same time, the lungs need to interface with all sorts of random toxins and pathogens in the air, meaning lots of ways for mutations to happen. Revised theory v2: More regeneration implies more cancer risk. Evolution tunes organs that encounter the environment for more regeneration and more cancer. It turnes organs that don’t for the opposite. But for highly structured organs, regeneration might not be an option. And if highly structured organs encounter the environment, cancer risk is still high. And now, ladies and gentlemen, the stupid pancreas: Organ Regeneration Cancer risk Pancreas Low-ish Moderate Superficially, this looks less exceptional than the lungs, with low-ish regeneration and merely moderate cancer risk. But the pancreas is more problematic for our theory, because that moderate cancer risk exists despite not being exposed to the outside world. Biologically, the reasons that the pancreas sometimes develops cancer seem understood, although complex. But as far as I can tell, there is no convincing explanation for why the pancreas is designed that way. Is it an evolutionary fluke? Is there some other subtle tradeoff? It’s unclear. So there’s no satisfying big-picture evolutionary trade-off to point to. Revised theory v3: More regeneration implies more cancer risk. Evolution tunes organs that encounter the environment for more regeneration and more cancer. It tunes organs that don’t for the opposite. But for highly structured organs, regeneration might not be an option. And if highly structured organs encounter the environment, cancer risk is still high. And the pancreas is weird. But we still need to face the final boss, the strangest organ of all. The small intestine Organ Regeneration Cancer risk Small intestine Extremely high Very low Bad news for our theory, good news for you as a biological organism. The small intestine does interface with the environment, and it replaces all its surface-level cells every few days. Yet it very rarely develops cancer. That’s despite the fact that it’s quite similar to the cancer-crazed colon. It’s also despite the fact that the “small” intestine makes up ~90% of the digestive tract’s surface area. What the hell? Biologically, the main explanation seems to be that the small intestine uses an ingenious defense strategy. My new favorite part of the body: While the surface cells of the small intestine are continuously being replaced, they aren’t themselves reproducing. Instead, carefully protected stem cells tucked into the valleys between the intestinal villi slowly produce “transit-amplifying cells”. Those transit-amplifying cells divide 4-6 times as they migrate to the surface, each eventually yielding 16-64 mature epithelial cells. Those spend a few days doing epithelial stuff, meanwhile sliding along with their siblings from the bottom to the top of whichever villus they happen to be on. When they reach the tip, they’re ejected into the digestive stream to die, merry Christmas. So, even if a mutation arises somewhere, it doesn’t really matter, because the cells are all on a conveyor belt towards death anyway. Clever, no? Turns out, the real hero isn’t the liver. It’s the small intestine. (The small intestine also uses a few other tricks: The surface cells are programmed to commit suicide if damaged even a little bit. The immune system is tuned to kill anything that looks even slightly funny. And it hosts huge amounts of detoxifying enzymes. But villi seem to be the really unique bit.) This is a huge challenge for our theory. Not only does the small intestine have low cancer and high regeneration, it has low cancer because of high regeneration. If the small intestine can do that, then why not the rest of the body? One answer is that it takes a ton of energy. Your guts shed ~40 billion epithelial cells every day, amounting to ~⅓ kg of tissue every week. Like the brain, your guts consume ~20% of total energy, despite making up only ~2% of body mass. Evolution doesn’t want to do that everywhere, because evolution doesn’t want you to starve to death. So, there isn’t just a trade-off between regeneration and cancer. There’s a three-way tradeoff between regeneration, cancer, and energy usage. But even if energy weren’t an issue, other organs couldn’t easily copy the small intestine’s strategy. For example, the colon is similar in many ways to the small intestine, but the colon doesn’t have villi. It needs to be flat, because the colon’s job is to extract water. If there were villi dangling everywhere, they’d be ripped off by the solid waste. The colon also hosts far more bacteria that produce toxic byproducts, meaning the colon’s cells need to be tuned to try to resist damage, instead of committing suicide. This also means that the immune system needs to be more relaxed about killing foreign entities. So even though the colon also replaces the epithelial cells (a bit more slowly) cancer is still common. (Or, imagine your skin was covered in tiny fragile villi. You’d look awesome, but they’d be constantly getting ripped off. If you wanted that to work, you’d need to make the villi stronger and more disposable, and… we just invented fur.) Revised theory v4 final (actually final) updated (2): More regeneration implies more cancer risk. Evolution tunes organs that encounter the environment for more regeneration and more cancer. It tunes organs that don’t for the opposite. But for highly structured organs, regeneration might not be an option. And if highly structured organs encounter the environment, cancer risk is still high. And the pancreas is weird. And actually, it’s not just a trade-off between regeneration and cancer, it’s a three-way trade-off between regeneration and cancer and energy usage, and various parts of that space may or may not be available depending on the job an organ has to do. So, a cancer vs. fragility tradeoff definitely doesn’t explain everything. But it does explain some things, somewhat, sort of. In biology, that’s pretty good. Is this bad? We’ve discussed various ways in which the body might appear to be crap. Let’s revisit those, and ask if the right tradeoff is being made for the modern world. Injuries. Your skin is calibrated for constant wounds, which most of us today don’t get. This leaves lots of repair pathways sitting around to be hijacked by skin cancer. Similarly, your bone marrow is calibrated to be able to recover from catastrophic blood loss. Today we don’t experience as much catastrophic blood loss, and we have blood transfusions, but all that generative capacity is still there to be used by leukemia and lymphoma. And whatever benefit there might have been to re-growing a limb is probably lower today, when we less often lose limbs. Best guess: It would be better if the body tried less hard to recover from injuries. Brains. Do modern people suffer fewer brain injuries than our evolutionary ancestors? It’s hard to say for sure, because brains are soft tissue. But the fossil record for upper paleolithic humans suggests between 2% and 34% suffered skull fractures, more than modern people. So you might think it would be better if the brain was tuned more towards fragility rather than cancer. But brain injuries are still common today. Around ⅓ of people experience a concussion sometime in their lifetime, because we love to drive cars at high speed, play dangerous sports, and survive to old age where stairs and bathrooms pose a risk. Also, for whatever reason, the brain is already tuned quite strongly towards fragility. Best guess: Maybe the current tradeoff is about right? Telomeres. Should the body re-lengthen the telomeres? On the one hand, we’re more likely to survive to ages where this is actually an issue. On the other hand, we’re also more likely to survive to ages where cancer is a danger, which is precisely where telomeres not getting re-lengthened is an issue. Best guess: Maybe the current tradeoff is about right? Livers. It seems that the liver is so regenerative because it needed to be. Ancestral humans were constantly dealing with parasites and bacteria and rotting food. When I started writing this essay, I figured this meant the liver was “over-specced” for the modern world. Today we have refrigerators and food inspectors and pasteurization. Our lives are much less harsh and involve fewer toxins than our ancestors. So, if calibrated for the modern environment, I figured that it would be better if the liver was a bit more fragile, but also marginally less prone to cancer.8 But… it’s not clear that this is actually true. Liver failure remains extremely common today. While we don’t ingest nearly as many toxins, we eat diets that lead to metabolic dysfunction, and we consume tons of alcohol, and many of us live in dense conditions where hepatitis can easily spread. We’re also more likely to live to an age where liver failure is an issue. Best guess: Unclear. We should stop doing stuff that causes liver failure. Menopause. Why do humans have menopause, unlike almost all other mammals? The most common theory is the grandmother hypothesis. The general idea is that reproducing becomes more and more risky as you get older. For most animals, evolution doesn’t care, because evolution’s goal isn’t to make you happy, it’s to maximize reproductive fitness. So, screw it, try to reproduce and let the dice fall where they may. But even after reproducing, humans can help the survival of their genes by providing resources for their offspring. So, for humans, evolution decided to turn reproduction off, so you can spend more time with your grandkids. In particular, with cancer, some theorize that continued cycles of estrogen cause damage to the ovaries, womb, and breasts. Menopause shuts this down,which may decrease the odds of ovarian / uterine / breast cancer. It’s a cute theory. But again: Menopause: Humans, killer whales, pilot whales, beluga whales, false killer whales, narwhals one group of chimps in Uganda. No menopause: Everything else, including elephants, other whales, lions, horses, zebras, dogs, rats, wolves, birds, reptiles, amphibians, fish. Some of this makes sense. Unlike toothed whales, Blue/Humpback whales are mostly solitary or live in loose groups. Mice don’t babysit for their grandkids. But what about elephants? Or hyenas? Or bonobos? Or orangutans? Or lions? Or sperm whales? All of these have social organizations where females contribute to the survival of their offspring, and yet they don’t have menopause. Anyway, is menopause the right tradeoff for the modern age? It’s hard to say. On the one hand, modern people live much longer, meaning the marginal cost of cancer is higher. On the other hand, people want to reproduce more at older ages, meaning menopause has a higher cost. (Both “to evolution” and “to us”.) Also, an ancestral woman began menstrating in her late teens, and then likely underwent many pregnancies, each followed by years-long periods of breastfeeding (which suppresses menstruation). An average modern woman experiences 3-5 times as many menstrual cycles. It’s very confusing. Best guess: No idea. Cell junk / diabetes / transplants. As far as I can tell, these are mostly unrelated. TLDR Cancer is bad because cancer is bad. Cancer is also bad because evolution made gruesome realpolitik compromises in the design of every part of the body to try to hold cancer in check. If we lived in a universe where cancer was impossible, we wouldn’t just not get cancer, our bodies would also be enormously more regenerative and longer lasting. In a sense, even if you don’t get cancer, cancer still hurts you, because your body was forced to take costly preventative actions. (Even if the barbarians never get over your city wall, you still had to build the wall.) Even if we someday completely defeat cancer, its legacy will live on in our genes until the point that we re-design ourselves. Screw cancer. Some people think linear DNA is easier to copy. Others think that linear DNA just happened by accident, but when it happened it was survivable because we happened to have retrotransposons, i.e. bits of DNA that build little machines to create new copies of their DNA and insert it into the genome. After the break in the circular chromosome, those machines started putting copies of their DNA on the end, because that’s what they do, and this made the break survivable. Those retrotransposons later became telomerase. ↩ This is teleological; let’s not let it come between us. ↩ This could happen because your immune system contains them. Or because oxygen and nutrients can’t diffuse inside the clump of mutated cells. Or because they run into a barrier of different cell types that they can’t outcompete. Or for other reasons. ↩ Hello biologists! You might be thinking, “Well actually, 90% of cancers turn telomerase back on; clearly telomeres don’t help that much; Dynomight why are you so bad?” That is approximately what the Dynomight Biologist thought, when pressed into service to review this post. True, having telomeres that wear down is not a magic bullet that makes cancer impossible. And yes, most cancers figure out how to turn telomerase on. But that is a linguistic fact. Your body has lots of mutated cells all over the place, most of which will never hurt you. Conceivably, we could have defined all mutated cells as “cancer”, with subcategories of “low risk to health” and “significant risk to health”. Then, telomeres would seem great, because it’s hard for cells to move from “low risk” to “high risk” without figuring out how to turn telomerase on. That’s hard to do through blind random mutation, which is one reason most of your mutated cells are in the “low risk” category. Cells do sometimes succeed in turning telomerase on, but it’s still a useful layer in body’s layered cancer defense strategy. We didn’t happen to define our words that way. Instead, we defined “cancer” to mean approximately “mutated cells that pose a significant risk to health” and we’ve invented other categories for other mutated cells (benign neoplasm, clonal expansion, hyperplasia, etc.) The “cancer” category excludes most cells that don’t turn telomerase on because telomere shortening is a good (albeit leaky) barrier between mutated cells and risks to your health. Just because Vikings sometimes get past your city wall doesn’t mean that a city wall is not worth having. Thank you for visiting my footnote. ↩ The precise reasons that salamanders can regrow limbs but most species can’t is somewhat unclear. You could speculate that salamanders tend to lose limbs more frequently, so it’s more worth it for them to pay the “cancer tax”. Or you could speculate that cancer isn’t as much of an issue due to their short lifetime. But do they actually have an unusually high frequency of needing to regrow limbs? And are they paying some kind of cancer tax? What would we even look at to determine that? Cancer rates vary in different animals for all kinds of reasons. ↩ Dead cardiac muscle is replaced with scar tissue. Dead neurons are replaced with a “brain scar” made of glial cells. ↩ Thyroid cancer risk is hard to rate, because it’s common but has a very low fatality rate. ↩ You wouldn’t want to make the liver unable to regenerate, but there are several “knobs” that might be tuned. Broadly speaking, the liver could be designed to regenerate more slowly, with more careful “proofreading” and slower/stricter cell-cycle checkpointing. Then liver injuries would take longer to heal, but would result in fewer mutated cells. ↩
It might seem a bit out of character for a powerful general—a fierce warrior—to go everywhere with a book tucked under their arm. But in ancient Rome, that was the figure that the great Scipio Aemilianus cut. He was known for training in philosophy as arduously as he trained at arms. Flash forward to General […] The post No One Is Excused From This appeared first on Daily Stoic.
Thoughts on surrendering to the here and now and doing the best with the information we have in any given moment
