Perhaps hobbies/careers that involve crafting a physical object have some built-in psychological advantage in generating feelings of fulfillment compared to other hobbies/careers?
This seems plausible given that virtually every knowledge worker I know fantasizes to some extent about working with their hands.
Quote I'm reminded of, from Matthew Crawford's Shop Class as Soulcraft -- long but I think worth reading:
Following graduate school in Chicago, I took a job in a Washington, D.C. think tank. I hated it, so I left and opened a motorcycle repair shop in Richmond. When I would come home from work, my wife would sniff at me and say “carbs” or “brakes,” corresponding to the various solvents used. Leaving a sensible trace, my day was at least imaginable to her. But while the filth and odors were apparent, the amount of head-scratching I’d done since breakfast was not. Mike Rose writes that in the practice of surgery, “dichotomies such as concrete versus abstract and technique versus reflection break down in practice. The surgeon’s judgment is simultaneously technical and deliberative, and that mix is the source of its power.” This could be said of any manual skill that is diagnostic, including motorcycle repair. You come up with an imagined train of causes for manifest symptoms and judge their likelihood before tearing anything down. This imagining relies on a stock mental library, not of natural kinds or structures, like that of the surgeon, but rather the functional kinds of an internal combustion engine, their various interpretations by different manufacturers, and their proclivities for failure. You also develop a library of sounds and smells and feels. For example, the backfire of a too-lean fuel mixture is subtly different from an ignition backfire. If the motorcycle is thirty years old, from an obscure maker that went out of business twenty years ago, its proclivities are known mostly through lore. It would probably be impossible to do such work in isolation, without access to a collective historical memory; you have to be embedded in a community of mechanic-antiquarians. These relationships are maintained by telephone, in a network of reciprocal favors that spans the country. My most reliable source, Fred Cousins in Chicago, had such an encyclopedic knowledge of obscure European motorcycles that all I could offer him in exchange was regular shipments of obscure European beer.
There is always a risk of introducing new complications when working on decrepit machines, and this enters the diagnostic logic. Measured in likelihood of screw-ups, the cost is not identical for all avenues of inquiry when deciding which hypothesis to pursue. For example, the fasteners holding the engine covers on 1970s-era Hondas are Phillips-head, and they are always stripped and corroded. Do you really want to check the condition of the starter clutch, if each of ten screws will need to be drilled out and extracted, risking damage to the engine case? Such impediments can cloud one’s thinking. Put more neutrally, the attractiveness of any hypothesis is determined in part by physical circumstances that have no logical connection to the diagnostic problem at hand, but a strong pragmatic bearing on it (kind of like origami). The factory service manuals tell you to be systematic in eliminating variables, but they never take such factors into account. So you have to develop your own decision tree for the particular circumstances. The problem is that at each node of this new tree, your own, unquantifiable risk aversion introduces ambiguity. There comes a point where you have to step back and get a larger gestalt. Have a cigarette and walk around the lift. Any mechanic will tell you that it is invaluable to have other mechanics around to test your reasoning against, especially if they have a different intellectual disposition.
My shop-mate Tommy Van Auken was an accomplished visual artist, and I was repeatedly struck by his ability to literally see things that escaped me. I had the conceit of a being an empiricist, but seeing things is not a simple matter. Even on the relatively primitive vintage bikes that were our specialty, some diagnostic situations contain so many variables, and symptoms can be so under-determining of causes, that explicit analytical reasoning comes up short. What is required then is the kind of judgment that arises only from experience; hunches rather than rules. There was more thinking going on in the bike shop than in the think tank.
This might be quite a 2025 centered perspective. But, it makes me curious about things like:
- Fidget Toys
- "Playing with the ground" when we sit outside and chat
- Trinket collecting
- Picking up a "good stick" while out on a walk
- Our preference for smooth over rough rocks
This post convinced me to buy 10 pounds of obsidian and basic knapping tools. I may give an update on whether knapping is fun and/or causes me severe injury, though I suspect that the learning curve is low hundreds of hours for proficiency and I'm unlikely to stick with it that long.
Don't start with obsidian! It's expensive, and the stone you're most-likely to cut yourself on. It's vicious. Wear leather gloves and put a piece of leather in your lap.
An old flint-knapping joke:
Q. What does obsidian taste like?
A. Blood.
I considered these factors. There are advantages too; the knapping subreddit also says it's easier to work, and with less dust the silicosis risk is lower. But the crucial one is it's much more exciting to make something molecularly sharp.
The cost seems acceptable because it's still lower than most hobbies. I'm mostly concerned that the required PPE will ruin the experience as quite a lot is recommended: gloves, mask, eye protection, good ventilation, a tarp to catch stray obsidian shards. Most of these are still needed for flint.
Maybe this is why knapping isn't so popular compared to other crafts like knitting and woodworking; it seems to be both tedious and just hazardous enough to avoid for rich societies that place extremely high value on health. People don't persistence hunt gazelles for fun; they use guns or more likely play football and videogames.
Oooh yeah dude I think you want to un-buy the obsidian. That is almost literally glass. You want chert!
Hangnails open up skin and very much killed our non-ancestors. It is a great place for an infection to start. I think it is just a hard problem to solve. Lots of animals have problems with their nails and claws. It is hard stuff poking through / mounted to skin, just a difficult thing to do well.
Lots of animals have problems with their nails and claws
Are you thinking of pets, or also wild animals? I figured part of the problem was that wild animals (and our ancestors) wore down their fingernails and toenails at approximately the same rate that they grow, so they would stay in a good configuration and everything was fine, whereas pets & modern humans have more nail problems because we under-use our nails, grow them out for aesthetics, etc. (But I could be wrong!)
You are overlooking the ancient and vibrant traditions of textiles, weavings, and basketry that still exist all over the world. In The Carrier Bag Theory of Fiction by Ursala K. LeGuin (1986), she proposes that the focus on stone tools is distorting our true human achievement, which is the development of the container.
There were probably a huge number of wooden tools that archaeologists have never seen because wood decays.
One thing that humans do better than other primates is throwing. Spears and other stone weapons probably had something to do with this.
I've had some experience with flint knapping and it is much more difficult than many people imagine. You have to determine the best place to remove a flake and then turn the stone over and strike it on the back side above the area where you want to remove the flake. This requires a lot of concentration and dexterity! And that is a very simplified explanation of how it is done. There are other things to consider such as a abrading the edge, developing a platform and more! I can certainly see how it could improve cognition as well as communication skills needed to explain the process to others. Oh, and you definitely want to avoid chert dust in you mucous membranes as this can cause silicosis!
As a failed flintknapper, I say that the most-surprising thing about stone tools is how intellectually demanding it is to make them well. I've spent at least 30 hours, spread out across one year, with 3 different instructors, trying to knap arrowheads from flint, chert, obsidian, and glass (not counting time spent making or buying tools and gathering or buying flint); and I all I ever made was roughly triangular flakes and rock dust. You need to study the rock, guess where the fracture lines run inside it, and then make a recursive plan to produce your desired final shape. By "recursive" I mean that you plan backwards from the final blow, envisioning which section of the rock will be the final produce, and what shape it should have one blow before to make the final blow possible, and then what shape it should have one blow before that to make the penultimate blow possible, and so on back to the beginning, although that plan will change as you proceed. It's like playing chess with a rock, trying to predict its responses to your blows 4 to 8 moves ahead.
So if I were to speculate on what abilities humans might have evolved on account of stone tool-making, I would think of cognitive ones, not reflexes or manual dexterity.
(I might be tempted to speculate on how the evolution of knapping skills interacted with the evolution of sex or gender roles. But the consensus on to what degree stone knapping was sexed is in such a state of flux that such speculation would probably be futile at present.)
There's already a lot of experimental archaeology asking what the development of stone tool technology over time tells us about the evolution of human cognition. I haven't noticed anyone ask whether tech development drives cognitive evolution, in a cyclical process; the default assumption seems to be that causation is one-way, with evolution driving technology, but not vice-versa.
Caveat: I've only done a fly-by over this literature myself.
- Learning to think: using experimental flintknapping to interpret prehistoric cognition. https://core.tdar.org/document/395518/learning-to-think-using-experimental-flintknapping-to-interpret-prehistoric-cognition [Abstract of a conference talk. You can find references to her later work on this topic at https://www.researchgate.net/profile/Nada-Khreisheh]
- Dietrich Stout 2011. Stone Toolmaking and the Evolution of Human Culture and Cognition. Philosophical Transactions of the Royal Society B: Biological Sciences, 366(1567):1050–1059. Analyzes different lithic technologies into action hierarchies to compare their complexity; also graphs the slow polynomial or exponential increase in the number of techniques needed by each lithic technology over 3 million years. Only covers the Olduwan, Acheulean, and Levallois periods.
- Antoine Muller, Chris Clarkson, Ceri Shipton, 2017. Measuring behavioural and cognitive complexity in lithic technology throughout human evolution. Journal of Anthropological Archaeology 48:166-180.
- Stone toolmaking difficulty and the evolution of hominin technological skills. Antoine Muller, Ceri Shipton, Chris Clarkson, 2022. Nature Scientific Reports 12, 5883 (2022). This study analysed video footage and lithic material from a series of replicative knapping experiments to quantify deliberation time (strike time), precision (platform area), intricacy (flake size relative to core size), and success (relative blank length).
FWIW I currently think it's bad practice to paste LLM output in a forum. It's like pasting the google search results for something. Anyone can ask an LLM, and the reason I'm here reading comments on a forum is to talk to humans, who have separate identities, reputations, and tons of cultural context of the forum.
1Yeah, probably. Sorry.
I didn't paste LLM output directly. I had a much longer interaction with 2 different LLMs, and extracted the relevant output from different sections, combined them, and condensed it into the very short text posted. I checked the accuracy of the main points about the timeline, but I didn't chase down all of the claims as thoroughly as I should have when they agreed with my pre-existing but not authoritative opinion, and I even let bogus citations slip by. (Both LLMs usually get the author names right, but often hallucinate later parts of a citation.)
I rewrote the text, keeping only claims that I've verified, or that are my opinions or speculations. Then I realized that the difficult, error-laden, and more-speculative section I spent 90% of my time on wasn't really important, and deleted it.
1I think, if you're going to do it, good form on LW is to put it in a collapsible section.
Here's an edited version of what Microsoft Copilot says about the amount of planning involved in some lithic technologies:
Acheulean Handaxes (~1.7 – 0.3 Ma)
- Characterized by bifacially flaked “handaxes” with broadly symmetrical shapes.
- Crafting a handaxe required the knapper to visualize a final form, select an appropriate flint or chert nodule, and execute a sequence of removals to achieve symmetry and thinness.
Prepared-Core (Levallois) Flake-Making Techniques (~300 – 100 ka)
- Used mainly by H. neanderthalensis and H. sapiens.
- The Levallois method involves preparing a tortoise-shaped core in several hierarchical stages so that a single, predetermined flake detaches as the final step.
- Achieving that predetermined flake shape demands extensive forward planning—mapping core geometry, platform angles, and flake dimensions before any major removal.
- Experimental studies show Levallois knapping is more intricate than discoid or basic handaxe manufacturing, requiring deliberate sequences and precision that attest to advanced cognitive organization.
Upper Paleolithic Blade Technologies (~50 – 10 ka)
- Homo sapiens popularized prismatic blade production: long, standardized flakes struck from carefully prepared cores.
- Blade knapping ranks highest in required dexterity, precision, and hierarchical planning, as each blade relies on strict core geometry and a series of carefully controlled blows.
Some late Acheulean sites hint at intermediate “proto-Levallois” strategies around 500 ka, suggesting a gradual cognitive shift rather than a sudden leap. Moreover, experimental archaeology today uses metrics like deliberation time, platform precision, and flake‐to-core ratios to quantify the cognitive demands of each technique—offering a window into the planning capabilities of our ancestors (1).
- Learning to think: using experimental flintknapping to interpret prehistoric cognition. https://core.tdar.org/document/395518/learning-to-think-using-experimental-flintknapping-to-interpret-prehistoric-cognition [Text unavailable, but you can find references to her later work on this topic at https://www.researchgate.net/profile/Nada-Khreisheh]
- Stout, D. & Semenov, V. N. “Flake-to-Core Ratio and Efficiency in Levallois and Blade Knapping: Experimental Perspectives.” Journal of Archaeological Science, 33(6): 782–796. (2006)
- Nadel, D. & Cochrane, E. “Timing and Planning in Lithic Reduction: A High-Speed Video Analysis of Stone-Tool Making.” Cambridge Archaeological Journal, 17(2): 233–242. (2007)
- Rots, V. “Facet Count and Platform Precision in Prehistoric Knapping: A 3D-Scanning Study of Levallois and Blade Cores.” Journal of Archaeological Method and Theory, 18(4): 345–362. (2011)
- Clarkson, C. “Quantifying Sequence Complexity in Lithic Reduction: Blade Versus Point Production.” Antiquity, 83(319): 998–1015. (2009)
Tangentially related, but I've always wanted to try the 3-stone technique for making a very precisely flat surface myself. It's something that really just requires three flat-ish stones of the same size (granite seems best) and some abrasives (crushed stone with higher hardness (and ideally, contrasting color) + sedimentation to control particle size). This technique was very important for the Industrial Revolution, since you can use these flat surfaces as the "bedrock of precision" for the manufacture of precise machinery, ... but it's something that anyone could have just done in the last 3 million years if only they had thought of it.
If you haven't heard of it before, I leave it as a puzzle to see if you can think of it :)
1I know how this works because my father made a telescope mirror in our basement. (He had to get it silvered professionally, but he did all the glass grinding/polishing himself!)
3[Epistemic status: channeling my physical anthropology professor.]
If you ever do it, please make sure not to leave any (wannabe) stone tools or stone tool fragments in the "wild", lest you excite some amateur (or non-amateur) human origin enthusiast who takes them as possibly true artifacts of prehistoric hominids and wastes their time trying to do something scientifically virtuous with them.
Your grandparents studied the Oldowan chopper so that your parents could perfect the Acheulean handaxe so that you, my friend, could build the Dyson sphere.
The Johns Adams quote: "I must study Politics and War that my sons may have liberty to study Mathematics and Philosophy. Our sons ought to study Mathematics and Philosophy in order … to give their children a right to study Painting [and] Poetry."
Not as immediately obvious as reflexively avoiding a branch, but on my model, you ought to think of language (first gesture, then speech) as an exaptation of cognitive adaptations for flintknapping. F5 in Old World monkeys is an interface between abstract goal representations and concrete action sequences, and F5 is believed to be the homologue of Broca's area in humans. Looks like F5 generates and interprets hierarchical act strings as such (i.e. regardless of modality). You can hill climb on hierarchy depth, breadth, goal maintenance duration, switching speed (goals are active until completed, losing track of a goal being premature goal inactivation), which lends credibility to this idea. I think of Broca's area as F5 with more atomic action categories + big model smell.
I have never made stone tools proper, but as a similar-ish experience, when I was a teenager I often spent some weeks in summer in a country home, and I had taken to a fairly manual hobby: making wooden swords/katanas. This mostly meant picking up decent pieces of wood (usually deadwood or some cutting leftover from construction work), taking a metal file, and slowly and surely, over the course of a few hours, filing off the shape to make something resembling a blade's edge, and a more rounded handle at the base.
Honestly, it was pretty pleasant and fun! Very repetitive work but there is something satisfactory in the sheer tactile experience of stone and wood. I expect making wooden tools would have also been a thing for most of human history; they just couldn't possibly survive as well as the stone stuff.
It is absolutely good for you to hone the skill of noticing when you need a tool, and making the tool you need out of whatever is lying around. That's the difference between "hit it with a rock" and "make a stone tool" -- you're changing the tool from your environment to be a better fit for the specific problem you're trying to solve. The skill of changing and customizing what our environments provide us is, of late, discouraged by advertisers.
Probably, though, tool and skill are the essential combination for this kind of agency. If you don't have the skill to know how something needs to be hit with a rock, then trying to hit it with a rock will be (sorry) hit-or-miss. You have to both know how your problem wants to be solved, and know how your tool wants to behave, in order to combine them properly. (anthromorphization here is intentional -- our brains have a lot of social hardware that we can run non-social stuff on if we wrap it in framing compatible with the social interfaces)
Most recent time I've used a stone tool was grabbing a river rock out of my pile of them to hone a scythe blade. I have more logs than rocks lying around where I'm at, so often a stick instead of a stone is my go-to improvised tool for applying a bit more force than I would be able to without its help.
I jokingly say that my bones might be stronger than most vegans in my weight class because I inhale so much chalk dust while teaching and walk to work in the sunshine, but it didn't occur to me that I was embracing my roots.
Yeah, people who eat a paleo diet without making their own stone tools are so fake.
Are there some people who do this for a hobby? You probably need the right kind of stone for that. How much time does it take for a relative beginner to produce one stone tool? If not too much, it could be an interesting summer camp activity.
Are there some people who do this for a hobby?
I was first exposed to it (flintknapping, but you can also make stone tools by grinding stone) by a granduncle when I was very young (5), and did it as a hobby for the last ~1.5 years of my undergraduate degree while I was living with my parents. I don't do it anymore because I live in an apartment and don't have easy access to a space where I could do it. It takes a lot of outside area because you produce a lot of sharp stone flakes and silica dust which you don't want in an area that is not well-ventilated.
You probably need the right kind of stone for that. How much time does it take for a relative beginner to produce one stone tool?
It doesn't work with any rock. You need materials that produce conchoidal fractures. The most typical ones to work with are flint, chert, obsidian, and dacite. I'm not a geologist, but what is referred to as "dacite" in the flintknapping community doesn't look a lot like what I see in the dacite Wikipedia article or Google Images (has a lot of inclusions, doesn't look like it would fracture the right way). If you look up "flintknapping dacite" you'll see it as a slightly glossy dark grey rock. More exotic materials are fossilized coral ("agatized coral") and quartz crystals (https://www.zmescience.com/science/archaeology/rock-crystal-dagger/). Non-natural materials can be used as well. Some people knap with non-natural glass and I think porcelain.
There are several websites that sell the rocks you need for very cheap if you don't live in an area where you can find them. They also sell traditional tools. The typical tools are other rocks (different kind) and antler. Sometimes copper is used, and I think it was used historically during the chalcolithic.
As to the difficulty of knapping, it depends heavily on the material. Obsidian (and by extension, probably manufactured glass as well) is by far the easiest of the materials I listed, followed by dacite. With the low level of skill I reached, I was only ever able to make decent looking tools out of obsidian and dacite. You need to strike the rocks very precisely to knap well, but for flint and chert you need to hit them a lot harder, which makes precise hits tougher IMO.
You can knap decent looking tools out of obsidian with not too much practice, and it is an extremely fun hobby that I would recommend quite highly. I was able to make do with YouTube tutorials and produced rough-looking blades with less than a week of practice (probably <10 hours). You'll break a LOT of blades while learning though, which really sucks if they were looking nice up to that point. You'll also cut yourself, especially if you don't wear gloves. The cuts are generally very clean and heal nicely, especially with obsidian. I wear glasses for my vision, but I would probably wear protective glasses otherwise. Apparently Ishi (https://en.wikipedia.org/wiki/Ishi) had a technique for dislodging shards of the material from his eyes (https://archive.org/details/yahiarcherysaxton00poperich/page/116/mode/2up?q=eye).
Epistemic Status: Memory. I learnt this (weirdly) in an astrobiology course at University. And through long personal interest in prehistory.
I know that the stone heads themselves are flint. To get it into the shape you want, you have to hit the flint with a harder rock. You hit it for (I think) hours[1] , in precise places around the edges. Inexperienced people may hit the flint too hard, when it's nearing completion, shattering hours of work, and requiring the process to start again. I have heard learning how to make good spear heads can take quite a long time.
- ^
[Edit: I think I was wrong about the Hours thing. In David Miles' "Tale of the Axe" he claims it takes ~20 minutes for an experienced individual to Knapp a flint hand-axe.]
1I imagine it would also be a lot easier if you leave near an area rich in the right type of rocks.
Earlier this year I visited Povery Point in Louisianna. The don't really have any stone nearby at all, so they traded for different kinds with people from as far away as the great lakes.
People tend to underestimate the scale of inter-cultural prehistoric networks. Humans are exceptionally good at sourcing materials.
I really like the mental picture of everyone waiting on Bob to return from the wilds with the special stones for the hunting points (or whatever).
I am also equally annoyed at things evolution didn't fix. One such thing that I'm particularly caring these days is the usage of scrotum supporters/tightees while running. I find them really tight and, obviously annoying. I just wonder why evolution didn't fix the problems caused due to running naked when we did that for millions of years.
Me too! I believe that evolution DID fix it--apes don't have this problem--and that the scrotum devolved after humans started wearing clothes. 'Coz there's no way naked men could run through the bush without castrating themselves.
Are their things about my body that are that way because of stone tool making?
Arguably a significative amount of our dexterity comes from an adaptation to craft objects.
I think you may have hit on part of the answer in the questions that you are asking. I was hoping to see some other commentor mention just exactly what these stone tools were used for and therefore what effect they had on our bodies. While you can use Stone to make all kinds of tools including mortars and pestles, which would help with processing grains and vegetables, the primary kind of stone tools that you're referring to here are projectile points. They were used to kill animals. This suggests that starting close to 3 million years ago our diet changed dramatically. From being seasonal frutarians and opportunistic gatherers throughout the year, we were able to bring down much larger animals and have a nearly continuous supply of meat. So when you ask, what kind of nutrient might you be missing out, I don't think it's that you're missing anything (as long as you eat meat) because we have been adapting to a highly meat-based diet for a very long period of time. Only since the onset of agriculture 10 to 15,000 years ago, did our diets start to shift towards grains. The consequence of that is pretty clear, obesity, see the Venus figurines, and diabetes and all of the diseases that excess calories can lead to.
I'm not sure if you understood this or not, but, I think Alex meant "nutrient" in a metaphorical way rather than a literal dietary way.
Curated. I'm not quite sure what to make of this point, but I am surprised I hadn't heard it suggested before.
I'm... not really sure what I expect but I am curious for someone to go make some stone tools and let us know, uh, was it good for you?
1Using the repetitive motions of making stone tools now could be good for developing manual dexterity. It might also give you time to reflect on the value of crafting while your hands stayed busy. But, lacking context, you might not get the same benefits from the work that your ancestors did.
Making stone flints now means separating the activity — stone tool making — from any original context(s), which would have been complex and social. What would an ancestral stone tool maker have needed to know, back in the day? To have the full benefit of stone tool making, I imagine the knowledge of literal hunger, at least some of the time, would play into the seriousness of the work. Humans lived in group/bands/tribes and were unlikely to be off on their own practicing in solitude for hours, others would have been near by, possibly working in parallel or tandem, or offering suggestions (verbally when there was language, perhaps gesturally before that). The stone tool maker probably included expertise at learning which rocks worked best and figuring out where those good rocks were found.
Having worked a lot with my hands over many years, never from physical need, I truly wonder how that would impact the making.
Am I missing out on any kind of "nutrient" by not doing it?
You may be missing out on some fun. I have to recommend "Caveman Chemistry" 's brief treatment of the subject.
Contrariwise, it seems odd that stone tool making is not a popular hobby, given what a crucial activity it was for 99% of our history.
Which suggests maybe we rapidly unevolved interest in it soon after the Stone Age.
We had many other handicrafts which continued to be useful and so persisted (even to this day - some only losing their usefulness very recently with industrialisation, continuing for now as hobbies not yet affected by evolution (eg knitting).) But stone tools are not among them.
Knitting is an interesting example, as it's a relatively recent invention (less than 1000 years old). Previously to make fabric you needed some kind of weaving method, which requires some kind of structure to hold the fabric. With knitting, you can do it anywhere, and just need a stick or two. It's an interesting technology in how important it was, in a very subdued way. Knitting uses more materiel, but you get a flexible and warm garment which you can produce while on the go (apparently Chinese caravan men would pluck out camel hair to continue knitting).
It's also interesting in how quickly it was abandoned as soon as cheap fabric was available from other sources - knitting is what grandmothers do (this used to make a lot of sense) and so was low status. It's only recently become a normal hobby.
Knowing how evolution works gives you an enormously powerful tool to understand the living world around you and how it came to be that way. (Though it's notoriously hard to use this tool correctly, to the point that I think people mostly shouldn't try it use it when making substantial decisions.) The simple heuristic is "other people died because they didn't have this feature". A slightly less simple heuristic is "other people didn't have as many offspring because they didn't have this feature".
So sometimes I wonder about whether this thing or that is due to evolution. When I walk into a low-hanging branch, I'll flinch away before even consciously registering it, and afterwards feel some gratefulness that my body contains such high-performing reflexes. Eyes, it turns out, are extremely important; the inset socket, lids, lashes, brows, and blink reflexes are all hard-earned hard-coded features. On the other side, I'll experience something unpleasant, and then be like "why is this still a thing??" Why didn't evolution remove this? Pretty often, it's clear that the unpleasantness just doesn't correlate with actually dying. Case in point; hangnails. And when some feature does actually kill people, it often causes equally many people to live, so removing it is not better on balance. And very often, there is simply no "small" mutation available to the genome that would incrementally reduce it.
And for a huge range of my experiences, natural selection has had approximately zero time to work with it. We are submerged in modernity. The species of Homo sapiens is generally considered to be about 300,000 years old. Looking around me, it can take a minute to think of something that was here even 200 years ago. At some point I started making a mental timeline, to help orient myself when I read about prehistory. All dates highly approximate, kya = kiloyears ago.
These may have had some influence on our genome, especially if the selection pressure was strong, but even 50kya is only 1/6th of our temporal range.
For many other milestones, like the first clothing, music, or use of fire, it is very difficult to have enough evidence to establish an earliest date, even within a factor of 2. But stone tools, the very implements that gave the stone age its name, have a rich archaeological record. It stretches back at least three million years. That's right; stone tools are ten times older than the existence of anatomically modern humans.
And this isn't one of those cases where there is a single oldest claimed instance which is far older than everything else. Archeologists have traced the development of stone tool tech throughout the millions, giving nicknames to the phases of techniques that ancient hominids used.
It's easy to forget how large a ratio can be. Ten apples feels like a normal quantity of apples. But a 1-hour dentist appointment is a lot different than a 10-hour dentist appointment. Not to put too fine a point on it (pun intended), here's the difference between the span of Homo sapiens existence, compared to how long stone tools have been in use:
X
XXXXXXXXXX
Many words have been written about the rejuvenating effect of a walk through nature, the now-rare sight of the milky way, or the way in which our modern life keeps us separated from the complexities of the ecosystems around us. But no one ever talks about how we don't knap flint like we used to.
Of course, the species immediately preceding sapiens was pretty similar to us. So any differences that stone tool use could have made have to be compared with the magnitude of those changes. But Homo habilis would be immediately recognized as different on sight. Even their bipedal gait was still adapting.
And it's not as though every person in the tribe would have been a lithosmith. There was presumably some specialization. But still. Three. MILLION. Years. All that duration of selection can't just be dust in the wind. Around here we pride ourselves on taking ideas seriously, especially when numbers are involved.
Are stone tools the reason I have fingernails instead of claws? (Doesn't seem like it; chimpanzees' fingernails look the same to me.) Was my blink reflex improved by being assailed with chipped projectiles? Do we have seasonal allergies because our mucus membrane was expecting to be coated in a protective layer of chert dust?
Anyway, I think this is starting to read like satire, but I am genuinely curious;