It is not a palatable fact for ideological egalitarians but there are rather profound differences in measurable intelligence from one region of the world to the next.
In some areas average IQs are around 40 and at the other end some areas report average IQs over 100. Moreover there seems to be a latitude bias. The low IQs cluster around the equator while the higher IQs tend to be further from the equator.
This is a phenomena which wants a scientific explanation and this article will persuade you of my own theory as to its cause. First let us look at some earlier explanations and why they are wrong.
The observation that human intelligence is not homogeneous across the world is an old one.
Europeans began exploring Africa in earnest following the development of quinine to combat the effects of malaria. Even before that, with their limited contacts through coastal trading it was apparent to Europeans that there was a large gap in technology between themselves and these “primitive” people.
Technology is self-evidently the fruit of intelligence, so even without administering IQ tests these early explorers of the world could hardly be faulted for presuming the difference in technology resulted from a difference in intelligence.
Moreover the new theory of Natural Selection seemed to provide a mechanism by which the sons and daughters of Adam might become different from each other in ability over time.
The latitude bias in distribution was known to these colonial era observers. They even had an explanation for it. I would call it the Winter Selector Theory. The idea was that in latitudes far from the equator humans have to deal with seasonal variations that produce survival challenges.
In particular, winters result in seasonal food poverty and challenges in maintaining core temperatures. To the extent that intelligence assists in surviving these periodic harsh conditions it would be selected for.
In contrast the Winter Selector theorists hold that given equatorial regions tend not to have seasonal food poverty and ambient temperature drops, that these are “easy ecologies”. Being easy ecologies they would not select for intelligence as strongly.
This Winter Selector theory does not stand up though. There are many selectors for intelligence and the “easy ecologies” of the tropics are not so easy on examination; they have their own perils and challenges.
Too much heat is as bad as too much cold. Monsoons, flooding, drought, insect swarms and infectious disease are as much hazards as seasonal food poverty. All these challenges can be mitigated by intelligence and so consequently would select for intelligence.
Also it must be said the winter ecologies are not inhabited only by humans. Squirrels, mice, bears and so on must also, and do, survive these supposedly harsh winter ecologies. Somehow they do that despite having smaller brains than any human of any ecology.
Also given brains must be fed to work and big human brains are especially hungry, seasonal food poverty should be a selection pressure against high capacity and therefore hungry intelligence.
It may be that winter ecologies select more for forward planning, and a tolerance for delayed gratification, because one must work in the summer to provide for the winter.
An inclination for planning ahead is not general intelligence problem solving though. It is more like a temperament than a computational facility.
Indeed squirrels gather nuts and seeds to store for consumption in winter. Bears lay down fat in the summer and hibernate in the winter.
Something else must be going on to explain these regional variations in intelligence.
As an amateur PC self building enthusiast, I often come up against the issue of waste heat being generated by computation. The more intense the computation, the more heat is generated. If too much heat is generated the hardware can be damaged.
Not too long ago I was forced to move a dual gpu PC build from an enclosed case to an open one to solve overheating. See the amusing video below.
We often tend to mysticise human intelligence but organic brain generated intelligence does share broad economic issues with silicon chip generated computation.
In order to process information, work energy is consumed and turned to heat. If that heat is not removed at least as fast as it builds up then the hardware, or wetware, can become damaged.
Removing heat itself requires mechanisms that consume work energy and produce waste heat as a byproduct. Ultimately heat removed from the site of computation ends up in the wider environment. The cooler the ambient environment the less energy is needed to be spent on moving it there.
We see in the world of data centers an economic preference for siting servers and super computers in colder climates. I first became aware of this during the early days of the bitcoin craze.
For example, I read about a big bitcoin mining operation, KNCminer, siting its bitcoin mining machines in the Arctic Circle for the economic benefit of cheaper cooling due to the environment.
Connecting the economics of information processing with this variation in human intelligence by latitude and we can see that, rather than being an easy ecology, equatorial regions are actually harsh environments for intense information processing.
With this in mind we should expect that humans in equatorial regions to face a selection pressure against too much intelligence even while there was a selection pressure for intelligence to solve survival problems.
Concomitantly we should expect a selection pressure against too much intelligence to be rather weaker in cooler climates where dumping waste heat is metabolically cheaper.
A few other factors may be altitude and nutrition.
I notice from the IQ map of the world that Nepal has especially low IQs compared even to India to its south. One reason for that might be that much of Nepal is of a very high elevation over sea level.
In this region heat is not a limiting factor but oxygen might be. The human body is an airbreathing engine and the brain is one of the more demanding organs. As much as 20% of oxygen intake is utililised by the brain.
In an environment where oxygen is relatively scarce, while also having an increased metabolic demand from the energy needed to move the body up and down the gravity well, as you have in mountainous regions, then that too would be a selection pressure against having too much intelligence.
Brains are not built out of nothing. They are hefty organs which are built from specific fats and proteins. It is an old wives’ tale, but true, that fish in the diet is “good for the brain”.
Besides the omega 3 fatty acids in fish, animal fats in general are important brain builders. Much of the evolutionary growth of human intelligence over our ape cousins may have been driven from switching from plant to meat based diets.
This may explain why for example the Japanese lead the world in IQ scores. Japan, as a island nation with not so much easily arable land, depends on fish sources for nutrition to a great extent.
All this still leaves unresolved the question of nature vs nurture, or rather genetic vs habituation.
If the economics of waste heat removal is more economic in higher latitudes and more expensive in equatorial regions due to ambient temperatures, then how much is an adaption to that baked into the genetics and how much is an habituation like tanning, calluses or sweating?
There is still a little hope for the ideological egalitarian with an emotional need for every human to have the same capabilities.
Perhaps if you take a person with an IQ of 40 from Sierra Leone to Sweden then their brain will habituate to the cooler temperatures and become more active?
Conversely we might expect a Swede who moved to Sierra Leone to find his brain slowed like a gpu with a cooling system clogged with dust.
Unfortunately for the ideological egalitarian it is very likely that habituation is the smaller part of the explanation of regional variations in human intelligence.
Generation after generation having to survive under the same climate will naturally experience selection pressures to that environment. In the same way as melanin content in the skin is substantially baked into the genetics, and not only an habituation like tanning, so an intelligence level economic for the ambient temperatures will be too.
Well there it is, my explanation for the profound variation in human IQ scores and their apparent bias in distribution by latitude.
I will call it The Climate Driven Computational Economy Theory of Human Intelligence Diversity.
Do you find it to be an satisfying explanation of the facts? Do you have any ideas on how to prove it?