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Executive Summary: The Trait Adaptivity Mental Model
If you only have three minutes, this introductory section will get you up to speed on trait adaptivity / context dependency.
The concept in two sentences: “strengths” and “weaknesses” are context-dependent; a more nuanced approach is to think of “traits” that are either “adaptive” or “maladaptive” under certain circumstances. If circumstances change, traits that are maladaptive may suddenly become adaptive, and vice versa.
Key takeaways/applications: the punchline, as we’ll get to, is a structural problem solving approach: when our traits don’t match up to the “selection pressure” of a certain environment that we find ourselves in, we can either try to modify our traits… or we can choose a different environment to which we’re more adapted. But watch out for n-order impacts; selecting for one variable can lead to unintended consequences on another.
Five brief examples of trait adaptivity / context-dependency:
Hungry Pig Right. The trait adaptivity mental model is perhaps most easily visualized via a sports analogy: is speed or strength and size more valuable? Depends if you’re an NFL wide receiver (speed!) or an NFL offensive lineman (strength and size!) The same characteristics (“traits”) that are “adaptive” to being a wide receiver are “maladaptive” to being an offensive lineman, and vice versa.
Trait adaptivity can also be seen in fields like engineering: specific materials are neither universally “good” nor “bad,” but rather more appropriate or less so in certain situations due to tradeoffs inherent in their qualities.
Henry Petroski discusses this in “ To Engineer is Human” ( TEIH review + notes). You wouldn’t want to build a bridge out of flimsy plastic, nor a child’s toy baseball bat out of iron and reinforced concrete, now would you?
Intelligence + evolution. As we’ll discuss, evolutionary biology is the original source of the “trait adaptivity” model.
It’s widely assumed that highly desirable traits like intelligence are strongly “selected for” by the environment, but that’s not always the case: cognition is energetically expensive, and as such, under low-food conditions, higher intelligence can actually be selected against – see Sam Kean’s “ The Violinist’s Thumb” ( TVT review + notes). Similarly, a polar bear’s ability to insulate itself is key to survival in the Arctic, but would doom it to death near the equator.
Changing business circumstances. Businesspeople need to be aware that if circumstances shift, the new context can transform strengths into weaknesses and vice versa.
As discussed in Gregory Zuckerman’s The Frackers ( Frk review + notes), gas-rich rather than oil-rich discoveries went from unwanted, to exciting, back to unwanted, as natural gas prices varied in relation to oil prices from 2000 – 2010. Similarly, locking in long-term leases to save on rent might once have been a good strategy for retailers… but if those stores become less popular thanks to online shopping, watch out.
It’s actually just a replay of a trend that happened a hundred years ago: Marc Levinson’s The Great A&P ( GAP review + notes) details how the preeminent retailer of the late 1800s and early 1900s had to rip up and reformat its stores every few years, thanks to the changing circumstances engendered by disruptive technologies like transcontinental railroads, refrigeration, and automobiles.
Investment strategy. Most great investors implicitly utilize the premise of trait adaptivity to excel: there are many potentially profitable investment strategies ranging from deep value to merger arbitrage to “compounders,” but everyone who’s been in the business for a while emphasizes the importance of finding and playing “your game,” i.e. staying within a circle of competence that makes the best use of your unique skillset, perspective, and interests.
As Patagonia founder Yvon Chouinard put it in an interview:I learned a long time ago that if you want to be a winner, you invent your own games. - Yvon Chouinard Click To Tweet
If this sounds interesting/applicable in your life, keep reading for unexpected applications and a deeper understanding of how this interacts with other mental models in the latticework.
However, if this doesn’t sound like something you need to learn right now, no worries! There’s plenty of other content on Poor Ash’s Almanack that might suit your needs. Instead, consider checking out our learning journeys, our discussion of the overconfidence, path-dependency, or opportunity cost mental models, or our reviews of great books like “ The Checklist Manifesto” ( TCM review + notes), “ Deep Work” ( DpWk review + notes), or “ The Great A&P” ( GAP review + notes).
A Deeper Look At The Trait Adaptivity / Context Dependency Mental Model:
Trait adaptivity shows up all over biology. Discussing avian intelligence in “The Genius of Birds” (Bird review + notes), for example, Jennifer Ackerman notes the trait adaptivity of being novelty-seeking:
“[being] open to the new and flexible [… is] risky. Flexibility carries costs […] Exploring the new and unknown takes time and energy, and it can get you into trouble.”
Two of the most fascinating examples of trait adaptivity in their natural context come from some of my favorite science books. Let’s dive right into some interactions.
Trait Adaptivity x Sleep
The first has to do with the rarely-discussed but critically-important concept of circadian rhythms, also known as our “internal clocks.” I go into this topic in depth in the “ sleep” mental model, but it’s worth reviewing here.
Chronobiologist Till Roenneberg’s wonderful Internal Time ( IntTm review + notes) details how surprisingly sophisticated internal clocks, capable of detecting and responding to the time of day, are present in organisms ranging from tiny marine dinoflagellates to the plants in your yard to, of course, humans like you and me. Why?
Well, it’s evolutionarily advantageous: meaningfully different environmental conditions exist during the daytime and nighttime, and organisms that can respond to and take advantage of the differences in those conditions will, over time, outcompete those that cannot.
Thus, circadian clocks evolved and worked over an extremely long period of time – but recently (post-industrialization) have stopped working very well, such that many of us (including yours truly) live on schedules that are wildly unsynchronized from the rise and fall of the sun. Research demonstrates that current work schedules, a legacy of previous eras, are in fact too early for about 60% of the population… our “ chronotypes” have gotten later over time, and we now (as a whole) wake up and go to sleep later.
“why [was] evolution so sloppy as to create a biological clock that cannot keep track of time properly?”
He answers his own question:
“the biological clock did not evolve in a time-free world.”
The clock, instead, evolved in a world where during the day, there was light, and lots of it; at night, there was very little, if any.
The modern world is very different: we’re indoors during the day with light exposure that’s orders of magnitude dimmer than the intensity of sunlight, but after dark, we’re exposed to internal lighting and screens that are orders of magnitude brighter than the outside darkness, making our poor body clocks very confused as to what time it is. (I’m oversimplifying here.)
And so our body clock – which was adaptive in the pre-industrialized environment, relative to the goal of synchronizing our wake/sleep rhythms with light and dark – all of a sudden isn’t adaptive to the artificial, socially-imposed requirement that we still get up at early hours (even though that’s not what most of us are programmed to do). This leads to 70% of modern Americans being sleep deprived.
Despite dramatically negative health and productivity consequences overviewed by Dr. Matthew Walker in “Why We Sleep” (Sleep review + notes), we keep these hours of “social time” thanks to culture / status quo bias, as I discuss more in that model.
Note that research – as well as my personal experience – finds that when you take people with widely varying chronotypes camping, and thereby put the trait back into the environment for which it adapted to, there’s still some variability, but it compresses dramatically, and most people get up much closer to sunrise than they do at home.
Application/impact: This trait-environment mismatch, as Roenneberg details, creates significant negative impacts to human health and productivity, and there’s an easy solution: reorient “social time” (i.e., when we go to work and school) to better align with our new circadian rhythms, in light of the changed environmental factors since those “social times” were determined long-ago.
This is a “ structural problem solving” approach that we’ll cover in more depth below.
Trait Adaptivity x Local vs. Global Optimization
“ Local vs. global optimization” refers to the concept that decisions that are optimal locally may not be optimal globally – for example, if you’re on a long hike, drinking all of your water when you stop for your first break might help you feel best right now, but you’ll regret it later in the day.
So far, we’ve been talking about how relatively fixed traits can become maladaptive when circumstances change. We’re now going to extend that discussion by applying inversion and looking instead at what happens to specific traits when we apply specific selection pressure to them.
Let’s again start with evolutionary biology, the foundation of this mental model. Aging is a surprisingly poorly-understood topic; one scientist in Meredith Wadman’s enjoyable The Vaccine Race ( TVR review + notes) noted that prior to research on telomeres and programmed cell death, aging was more or less just a catch-all bucket for otherwise-unexplainable phenomena.
Our knowledge of aging has improved meaningfully since then, and we know a lot of causative factors, such as oxidative stress; Geoffrey West does a nice job of quantifying some of this in Scale ( Scale review + notes). But it’s still a multicausal phenomenon that’s not fully understood: whycouldn’t we live longer than we’re programmed to, when it seems like a few genetic modifications would get us there?
In the wonderfully illuminative Other Minds by Peter Godfrey-Smith ( OthM review + notes) – which, incidentally, is the single best book on trait adaptivity you can read – Godfrey-Smith proposes, on pages 162 – 169, one possible explanation of aging. The major selection pressure in nature is mating: those animals that survive long enough (and are “attractive” enough to potential mates) to pass on their genes will, tautologically, pass on their genes.
So, in an example of local vs. global optimization, genes that provide some benefit in life up to the point of mating, but are detrimental in the longer run – or genes that are simply unharmful before mating, but harmful in the longer run – will not be selected against, and passed on from generation to generation. A human example might be the BRCA1 mutation that causes some women to be at higher risk for breast cancer: since breast cancer typically doesn’t crop up until women have already borne children, the mutation is passed along.
Application/impact: Whenever you are “selecting for” specific “traits” in your life, whether in yourself, in a major purchase like a house or a car, or in skills you want to develop, make sure that you’re considering the big picture and other possible scenarios besides the present, and how those traits would or would not be adaptive in those different circumstances.
Memorable example to drive the point home: one of my clients, an economics PhD, told me once that “market preferences change” for dating partners from the early 20s to the early 30s. The qualities that make someone an exciting fling in college might make them a terrible spouse (or vice versa), and the same may well be true for cars (think sporty coupes vs. safe, reliable minivans.) See the discussion in the hyperbolic discounting mental model.
Trait Adaptivity x N-Order Impacts
“ N-order impacts” refers to the “and then what” – not just the immediate consequences of an action, but the longer-term “ unintended consequences” – for example, providing a payment for dead rats can incentivize college students to trap and kill rats… but also to breed rats.
Let’s add a new wrinkle by changing the selection pressure from natural to artificial; i.e. driven by human agency. Continuing with biological examples for a moment, consider our long history of selectively breeding plants for desired traits (bigger grains, higher yield, resistance to disease).
By and large we’ve been very successful at this, but something has been lost along the way: by actively selecting for the hardiest and biggest-growing tomatoes, we inadvertently select against other qualities – like, for example, taste. Any foodie will tell you that commercially-grown store-bought tomatoes taste like cardboard; the same goes for strawberries and many other types of produce. You don’t know what flavor is until you’ve tasted a homegrown tomato.
But if you’ve grown tomatoes, you’ve also seen the tradeoff: heirloom tomatoes can be finicky, prone to flaws, and don’t stand up very well to transport over long distances or storage for extended periods. While I haven’t verified the science in Mark Schatzker’s The Dorito Effect, which discusses these sort of tradeoffs in more depth, I do believe that his assertions are directionally accurate.
Transitioning to the business world, Clayton Christensen’s “ The Innovator’s Dilemma” ( InD review + notes) – which is great research but only an “okay” book – provides a good example of how selecting for specific traits leads to unintended consequences. (I discuss it more extensively in the “ local vs. global optimization” mental model.)
Businesses, by and large, evolve to be good at what they do, so the best businesses tend to, for example, have defined processes that optimize for efficiency, rigorous financial management that ensures capital is effectively deployed, and so on. Christensen argues that extensive research demonstrates that the very “traits” (my word) that are “selected for” (again, my word) by the competitive environment lead to successful businesses being “maladapted” (yup, still my word) to major changes in the external environment.
Application/impact: be aware that inevitably, by “selecting” for (or, in another context, incentivizing) one specific set of traits, you may inadvertently pick up others you don’t like. Back to the dating example, consider checking out the dating-partners section (pages 361 – 362) of Jordan Ellenberg’s How Not To Be Wrong: The Power of Mathematical Thinking ( HNW review + notes) and see if you can reframe his discussion in terms of selection and trait adaptivity.
Trait Adaptivity x Structural Problem Solving (x Memory)
“A system that renders information less accessible over time is therefore highly functional, because when information has not been used for longer and longer periods of time, it becomes less and less likely that it will be needed in the future.
On balance, the system would be better of setting aside such information… [our memory… makes a bet that when we haven’t used information recently, we probably won’t need it in the future.
We win the bet more often than we lose it, but we are acutely aware of the losses… and never aware of the wins.”
That quote, from Daniel Schacter in “ The Seven Sins of Memory” ( 7SOM review + notes), really elucidates the trait adaptivity model. Our flawed memory is an adaptive trait, but its malfunctions are far more salient than its generally adaptive nature.
Imagine if we had perfect memory. If we had to sort through lots of old, irrelevant information to find what we were looking for – as a metaphor, visualize what would happen if your new emails were randomly assorted among every email you’d ever received, and you could never delete any of them or get them out of your field of view – we’d be clamoring for our nice, forgetful memories.
This isn’t totally made up: Schacter cites the example of a famous Russian mnemonist:
“he was unable to function at an abstract level because he was inundated with unimportant details of his experiences.”
Schacter also references how the same neurological mechanisms that enable autistic children and adults to have amazing memories can prevent them from effectively generalizing.
So, how do we use other adaptive traits to overcome this occasionally non-adaptive trait, i.e. ourmemory?
“ Structural problem solving” is my favorite mental model. (Like Howard Marks has a lot of Most Important Things, I have a lot of Favorite Mental Models.) Structural problem solving basically refers to an outside-in approach that, in contrast to the extremely maladaptive “ grit” (brute-force willpower) approach that is popular, instead emphasizes finding structural ways to make problems easier to solve: for example, if you can’t remember a loved one’s birthday, use Google Calendar.
The idea here is pretty straightforward: humans in general are pretty good at certain things ( cognition), and not so good, relative to the rest of the animal kingdom, at various other things (speed, strength, etc). But rather than trying and failing to make ourselves as strong as a gorilla and as fast as a cheetah, we used our best traits to structurally solve our lack of strength and speed by using technology, ranging from carts and horses to automobiles and airplanes.
Often, if you find yourself in a situation where your traits are maladaptive to the situation, your best bet is taking a structural approach to reframe the problem into something for which your traits are more adaptive. Humans, for example, have a lot of embedded cognitive biases that are part of our subconscious schema and affect the way we view information: integrating an understanding of these cognitive biases into our schema and constructing external processes (like checklists, as discussed in Atul Gawande’s The Checklist Manifesto – TCM review + notes) can thus, at least partially, prevent us from having to deal with the consequences of bad decisions repeatedly.
In fact, the whole genesis of Poor Ash’s Almanack was, ironically, me finding myself reading Daniel Schacter’s aforementioned The Seven Sins of Memory, a book about the follies of human memory, for the third time, because… you guessed it… I’d forgotten a lot of it.
A large body of evidence suggests that it is much more effective to use external “structural” reminders (which we’re good at creating!) than attempting to improve our memory by brute force (which we’re not very good at).
If you want proof of this, look no further than repeat National Memory Champion Tatiana Cooley, who – in her everyday life – doesn’t use any of the fancy mnemonic techniques she uses for memory competitions. What does she actually do? Well, according to a New York Times profile:
Despite her memorizing accomplishments, Ms. Cooley described herself as notoriously absent-minded — someone who lives by Post-it notes. ”I make grocery lists,” she said, ”and always come back forgetting to buy the one thing I really needed.”
“Memory palace” mnemonic techniques used by many of these competitors, explored in depth by journalist Joshua Foer in Moonwalking with Einstein (MwE review), are amusing to read about but not whatsoever useful in everyday life. After winning the 2006 Memory Championship, Foer still had trouble remembering where his keys were.
“many of the imagery techniques are complex, require considerable cognitive resources to implement, and are therefore difficult to use spontaneously. The first few times you generate bizarre mental pictures and stories to encode new information, the process may be challenging and fun.
But the task of repeatedly generating memorable images can eventually become burdensome enough so that people stop engaging in it. In one study… [barely one-third of older adults] reported using [the mnemonic] techniques in their everyday lives.”
Clearly, this is not a problem to be overcome with willpower – so, structural problem solving it is. Don Norman provides an irrefutable defense of this paradigm on pages 285 – 288 of The Design of Everyday Things ( DOET review + notes), noting that we’re at our best when we use our brains to amplify their power rather than trying to rely on them without external aids:
“In Ancient Greece […] Socrates complained about the impact of books, arguing that reliance on written material would diminish not only memory but the very need to think, to debate, to learn through discussion […] but over the years […] human intelligence has certainly not diminished […]
Does the fact that I can no longer remember my own phone number indicate my growing feebleness? No, on the contrary, it unleashes the mind from the petty tyranny of tending to the trivial and allows it to concentrate on the important and the critical.
[…] the power of the unaided mind is highly overrated. […] Human intelligence is highly flexible and adaptive, superb at inventing procedures and objects that overcome its own limits. The real powers come from designing external aids that enhance cognitive abilities.”
Or, in other words: reframe the problem of memorization to utilize our adaptive traits (ingenuity and tool use) rather than our maladaptive traits (our flawed memories).
A great example of this in the real world is GPS vs. “The Knowledge” – the famous, brutally difficult exam required of black-cab drivers in London, in which they more or less memorize every street, every nook and cranny, of the notoriously anti-grid-like city.
“Three years of complete financial stress, family stress — studying for 13 hours a day, seven days a week.”
It’s also one with low to no marginal utility versus GPS: even the “ cultural guide” elements of the job (“hey, I want a bar like this” or “oy, where did this happen”) can be replaced by Yelp and Google respectively.
Application/impact: improving upon weaknesses is always an admirable goal, but it can often be equally or more effective to reframe problems in a structurally-solvable manner than to attempt to brute-force trait improvement. If you can’t remember a loved one’s birthday, put it in your calendar!