Once I decided to undereat while travelling. The result was that for the first month I was in hypomania almost, very excited about things and places. I also slept much less and kept away from easy pleasures. At some point, at the end of the month, this hyper-functional system broke down, and I realized that though I thought I was dancing, in a club, I was actually not taking my feet of the ground. I suspected I might be tired, and went to bed. 17 hours later I woke up. I interpreted that as "I put myself in emergency mode and became more interested and productive, still this nitro didn't get me the nourishment I needed after a month, so the body gave up and sent a message to the mind (or the medial prefrontal cortex) saying - That was all you had. Give up now, hope for a better crop tomorrow."
I mostly agree with this. However, this point seems reversed:
In the EEA, both were probably somewhat correlated with interpersonal trust and reciprocal altruism. When there are lots of people, a reputation for backstabbing spreads more rapidly and has more consequences.
When there are more people your chances of meeting the same person again are lower, also this makes it hard to keep track of reputations. To the extent abundance correlates with high interpersonal trust and reciprocal altruism, the causation goes the other way.
The curve will be particularly complex. When there's no one. No curve. Very few, then it's worth to collaborate even when they backstab you. Specially if the environment is super-dangerous. You want to create a story according to which they didn't betray you at all. Anything, as long as the mutual knowledge is still on the friends side. Bigger numbers: Something close to Dunbar number would probably be where you most need to signal trustworthiness, and from then on, the more there are, the lowest is the cost of free-riding.
What does science say?
There's some evidence that hunger may improve memory. Is this the kind of evidence you're looking for?
I have lowered my prior for these kinds of explanations being correct; maybe it's the sudden surge of nutrients that does something to the memory? Who knows, but it reads like evopsych-inspired version of the narrative fallacy. If it works empirically, great, if it doesn't I'm not going to ask "why did my brain not react as if being saved from starvation"?
Warning: armchair evopsych speculation follows.
Related to: Summer vs Winter Strategies
A couple months ago, I had a large amount of tedious work to do. Whenever I sat down to do it, I would be distracted by other, less mentally straining or more interesting tasks. I decided to try an experiment in disconnecting distraction: I removed everything on my laptop that wasn't that work, and travelled to a remote rural location. I had no internet access, books, or any other things to keep me occupied. I decided to take further advantage of the precommitment opportunity by not taking enough food for the full trip, so I would be fasting for 2.5 of the trip's 6 days.
I managed to get a large chunk of the work done, so I count the trip as successful and am planning to repeat it for longer time periods. The most interesting observations I got were the effects it had on my mental state. There were two clear effects.
* First, really strong cravings for various forms of distraction, together with a sort of severe, restless mental pain at not having them; I tried to sleep as long as possible because that was more entertaining than the mind-numbing boredom of hours and hours of the work. The mind seems to adjust for entertainment like it does for several things - having more entertainment than your "expected entertainment" setpoint raises the setpoint and makes you happy, and having less than the setpoint lowers the setpoint and makes you unhappy.
* Second, by the end of the six days, a weird feeling of agency, high willpower, clarity about goals and how to achieve them, and a stronger-than-baseline desire to not socialize. These effects were really strong; they lasted for two or three days after I returned from the trip. This did not feel like the hypomania that caffeine (with no tolerance) induces in me; I felt calm and conscientious.
At the time, I attributed all of the mental effects to setpoint-lowering, commitment/consistency (seeing yourself as "the type of person that does X"), and placebo. Later, I thought of another explanation: all of the conditions in the experiment, when they were present in the EEA, were symptoms of scarcity of resources. They're all signs of the environment being generally hard to survive in, or of a lowering of the environment's carrying capacity, e.g. by a drought or a heatwave.
To review the conditions:
* I had no contact with other humans.
* I was fasting for the last half of it.
* The area was dry and hot; the plants and insects were generally hostile.
* There was little animal life. This, together with the lack of music, ensured silence, except for inorganic sounds like a door banging in the wind.
* I was undergoing withdrawal from all of my various entertainment addictions - to music, to games, to movies, to porn, to reading interesting or funny or insightful things, to social interaction.
* I was doing unpleasant work for most of the day.
It seems reasonable that the mind would be adapted to function differently in resource-scarce environments than in resource-abundant environments, and I'd guess that evolution would deal with this by creating flexible adaptations activated by immediate circumstances rather than by creating unmalleable fixed adaptations, because there's gene flow or because environments change or because humans move around.
So it might be useful for us to impose conditions that would have been evidence about optimal behaviour in the EEA, in hopes of causing us to more readily execute those behaviors. I'm not sure how effective this really is; I still think the effects from my experiment were largely from setpoint-lowering and commitment/consistency.
For the scarcity-versus-abundance spectrum, some thoughts:
* In the EEA, the scarcity-versus-abundance spectrum was probably highly correlated with population density.
* In the EEA, both were probably somewhat correlated with interpersonal trust and reciprocal altruism. When there are lots of people, a reputation for backstabbing spreads more rapidly and has more consequences.
* In modern first-world countries, people are probably more in the abundance mindset than the EEA norm, because resources are abundant and there are people everywhere.
* I think it's likely that different people tend to different ends of the spectrum, because of genes, experiences or surroundings. I think some of my own abnormalities can be explained by being further towards the "scarcity" end than most people; this post might look biased to people on the other end.
* In scarcity environments, there's less incentive to engage in costly signalling games, because there are less people to signal at, they matter less because they have less resources, and the costs of signalling are more painful. This could be bad (because much of the worthwhile stuff humanity does - art, altruism, people trying to get rich, verbal intelligence - seems to be done mostly to signal) or it could be good (because people don't handicap themselves). People in scarcity environments might have more clarity because self-delusion might often be done in order to credibly signal.
* There are two ways to deal with hard problems. You could solve them. Or you could cry for help, by loudly complaining, showing off your helplessness and incompetence, perhaps even by self-sabotage. But crying for help is a good strategy only if there are friendly people all around you with resources to spare who believe you have resources (or shared genes) with which to reciprocate (or onlookers who would be signalled at, and who matter because they have resources). So people in the scarcity mindset might try harder to agently get things done, while those in abundance mindsets would rely more on other people.
* On risk-taking: Abundance environments have stronger social safety nets and more of a resource cushion, so losses won't kill you. On the other hand, scarcity environments have less to lose and less people to see you fail. If there's a "cutoff" of resources under which you won't survive, and if you expect to not survive, then risk-taking at even odds would probably increase utility. Similarly, for planning/conscientiousness: Abundance environments have more of a future to plan for. On the other hand, scarcity environments have less of a resource cushion and social safety net. Planning would be better in more predictable environments, but I don't know which environments are more predictable. r/K selection theory might also be relevant here, but I'm not sure which of scarcity/abundance is which of r/K; the more predictable one would probably be more K.
Things to think about further:
* Is this sensible, or is it confirmation bias + just-so stories + cherry-picking? What does science say? (I couldn't find very relevant things; there are some papers about using r/K selection theory to explain differences between people, and some sources saying that cultures with higher risk and mortality conform more to traditional gender roles.
* If it's sensible, which end of each spectrum should we aim for? How can we easily signal scarcity/abundance to our "savannah minds"?
* What other things can we signal to our savannah minds? What EEA changes could we simulate to cause useful changes in our behaviour?