Demographics, Territory and Temperament


Demographics, Territory and Temperament 


This, and the next several essays, build upon concepts developed in previous essays beginning with What is a Social Species, and a later set beginning with From Utilitarianism to an Evolutionary Morality.  These new essays will mix those two tributaries that are at opposite ends of an evolutionary timeline: our paleo-morality and our modern moral failures.  This set was triggered by reading the phrase “Ice Age refugia”1 while I was writing about the rape of Neryl Joyce and ‘Alice’ in Evolutionary Sexual Morality: From Sex Drive to the Pair Bond – Carl Wilson (  I made a connection between Ice Age refugia and modern rape, an unusual pairing which began with the thought that rape was probably not a sexual behavior in our paleo-morality, and that it somehow and somewhy developed later.  To get here – to these essays – I also had to develop the concepts of paleo or evolutionary morality, which I did in four previous essays.2  There, where I am going, is how behavior is controlled within small-scale foraging hunter gatherer social groups, and then to how and why behavior is insufficiently controlled in civilization.

My goal is to establish a sociological/territorial model of human behaviors rather than the conventional Western individual/psychological model, by setting our behaviors within the context of social groups and their dynamics:

“In this essay I offer a sociological explanation of temperaments and behaviors based upon the needs of an intelligent, ground dwelling, social species, and once upon a time, prey, specifically, H. sapiens.  We have an evolutionary sociological history, a path dependency at our social level.  Our brains have been optimized over the course of that history for living in small social groups in a dangerous ecology – the mixed open grass and wood lands of the African savannah, home of herbivore herds and hungry carnivore predators.  We are omnivores, suspended between those poles of prey and predator and, lacking any significant defensive or offensive weapons and muscularly weak, we were more prey than predator.  We are now more predator than prey.  We retain the morphology and physiology of prey, and have overlaid them with a cultural accumulation of technical – that is, non-biological – weapons of a predator.  From prey to predator is an astonishing evolutionary narrative arc and it has significant consequences.  I posit that we retain some of the sociology and psychology of a prey social species, specifically, danger perception and response mechanisms.”3 We also lack a major temperament of natural predators, but of that, more in a future essay, because that occurs later in our evolutionary history.

That we were once very much more prey than predator and retain the temperaments of a prey is a significant factor in our behavior.  In succeeding essays, I will set out the proposition that at least one major element of social control of our paleo-morality is based upon fear.4Looking back, I posited that our paleo-chemo-hormonal behaviors are released by the reception of signals.  Looking ahead I will suggest that the expression of these behaviors is regulated by social controls in the context of tightly bonded small-scale social groups typical of foraging hunter gatherers.  This is ‘evolutionary sociological path dependency.’  Our path to here is the major factor in what we are now.


Our large-scale demographics may be summarized in three words: inexorable population increase.  There have been decreases at times, particularly during pandemics and famines, but overall, our population has increased – dramatically.  We have defeated many of our predators from bacteria to worms to leopards.  We now lack adequate predation and ecological constraints, and have escaped most the population controls typical of animals.5  This is an independent factor that has interacted with all of the other factors and it raises the question: how have we adapted or accommodated to our population increase?

Social Group Size

Our small-scale demographics may be summarized in two words: Magic Numbers – the size of our social groups.  Ethologists and anthropologists have long observed that each species of the primates has a maximum, minimum and optimum group size.  They were called Magic Numbers because they while they were observable, they were not explicable: the reason for them could not be specified so they are like magic.  The Magic Numbers are another independent factor in our social evolution.

We are not a solitary, herding or flocking animal.  We were ab initio a social species whose social structure is composed of a mosaic of small-scale groups characterized by membership boundaries: in-group and out-group.  For humans in foraging hunter gatherer societies, the typical range is from about 25 individuals at the low end to about 150 at the high end.6

“We are a neurologically and behaviorally complex social, tribal, and territorial species.  Mental capacity, effort and time are required to form individuals into a group, to maintain that group, and to function within the group.  Our brain has limited information bandwidth capacity and processing power.  The upper limit to a group size is set by the intensity, complexity, variability and duration of the combinations of individual relationships intersecting with that mental capacity.  Keeping track of individuals, who is doing what to whom, who is dominant and submissive, who grooms whom, etc., is one of our major functions.  In the center of the group is the mother-child bond, around that, the female-male pair bond, and wrapped over both is the penumbra of tribal care of each other.  There are a lot of interactions to keep track of, and being social takes time and mental capability.”

In the 1990’s, the anthropologist Robin Dunbar,7 advanced the social brain thesis to explain the upper limit which is set by the information bandwidth and processing power of our brains.  He did a major statistical study on primate brain size vs social group size to support the idea that our relatively large brain size evolved to solve the problem of bonding a number of highly complex and variable individuals into a social group that met both individual and social needs to an adequate degree.  There is an intimate relationship between behavioral complexity, brain size,8 and social group size, each affecting the other.9

The relationships may be inverted: increased brain size, evolved for an unspecified reason, allowed us to form and to operate effectively in social groups within our Magic Numbers.  This would account for relatively large brained primates who are solitary.  There may well be several factors in the evolution of large brains and sociality. Dunbar’s social brain hypothesis, like so many evolutionary hypotheses, has its critics.  What is secure is the observation of the Magic Numbers.

The optimum human social group appears to be around 50 individuals.  A major factor in determining the optimum number is the richness of the territory occupied by the group and the time required to locate, obtain, process, transport and consume those resources.  A resource rich territory will allow the social group to expand toward the upper bound and vice versa.  The lower limit has received less attention because most relict hunter gatherer societies are larger and thus we have no observational evidence.  Presumably a group smaller than 25 individuals is at a survival disadvantage, and individuals of such a group might well attempt to amalgamate into a nearby group.

We are also a fission-fusion species: we break into smaller groups, as small as 2 or 3 and up to 7 – 10 during the day – fission – for specific purposes and tasks, and re-unite later in the day – fusion.  Smaller groups make decisions faster and cooperation easier due to reduced information burden.10 This increases task performance efficiency.  Fusion later in the day increases the grooming, eating and sociality arenas, and promotes defense against nocturnal predators.  The size of fission groups forms other Magic Numbers.11

There is another number of great importance: the low bound on the number of breeding individuals in a group that is required to avoid genetic in-breeding.  With tongue in cheek, I’ll suggest the Exogamic Number, but the technical term is ‘minimum viable population.’12  Estimates vary from around 80 to a higher estimate of 14,000.  Those numbers depend upon the assumptions used to generate it.  The number is neither directly observable nor experimentally verifiable, and its numerical value is unimportant for this essay.

Those estimates for the minimum viable population do not include the non-breeding individuals, the young and old.  Dunbar’s Number for the high limit includes the non-breeding individuals.  The implication is that our social group size is typically smaller than our out-breeding group size plus the non-breeding individuals, and therefore we have built in out-breeding behaviors.  Humans and other primates evolved the mechanism of late adolescent transfer from their natal social group to another carrying with them genes, parasites, diseases, and cultural knowledge.  For humans, it is the female who transfers.13  There are mechanisms for incorporating transferees into the social structure of the adoptive social group.  Transfer and amalgamation will be discussed in more detail in a future essay along with other out-breeding behaviors.

In the section on Demographics (above) I asked the question “how have we adapted or accommodated to our population increase?”  This section on social group size has added a demographic constraint to the problem of population increase: Dunbar’s Number sets the upper bound for the group size.  There has to be a mechanism to accommodate population increase and yet maintain Dunbar’s Number within each social group.  As groups increase above Dunbar’s Number – become supra-DN – intra-group conflict will increase and at some point, the group will fission into two sub-groups.  At this point there are two major possibilities, sub-dividing the existing territory or forcing one fission group to take up new territory.  So, it is to territory that I turn next.

Territory and Temperament

We are a tribal and territorial species.  Social group boundaries – we and they – interact with territorial boundaries – ours and yours – yielding a mosaic of small groups occupying a mosaic of roughly defined territories with sufficient resources for survival.

“About 9 PM I like to go for a relaxing walk.  In the winter I avidly sniff the smoke from wood fires and get to thinking that we have a long association with wood fire – probably our oldest and most fundamental technology.  For millennia out of mind the smell of burning wood has been a signal of hearth, home, happiness, and warmth.  We are naked apes without an insulating fur coat.  Fire dries and warms, cooks our food, lights the night, and deters predators.

“But the smoke of burning wood can also signal danger.  Wildfires, yes, but more significant is the smoke of a campfire of another group.  They are too close.  Who are they?  Are they neighboring tribes with which we occasionally exchange mates and gifts?  Or are they someone we do not know?  Why are they there?  Where are they going?  What will they do?  Are they just passing through or do they intend to contest our territory?  What shall we do?  Just thinking of this scene, I can feel the stomach acid churning.  This is our land.  The imminent danger is to our territory, our land that we know so well, roam so widely and freely use.  We cannot lose those resources.  If we lose, we have to move elsewhere, possibly to a lower quality territory or failing that, conquer someone else’s territory or starve.  Wood smoke signals home and friend on the one hand, and fearful danger on the other.  This is our land.

“Two words that are intimately tied together in that description of territoriality, our land, form the nucleus of this section.  Our: we are a social rather than an individual or herd species.  Land: we are perforce territorial.  We are a territorial social species.  We hold land and its resources as a group, not as individuals; and as a group we hold our territory through time beyond the lifespan of any individual.  Our group, our land.  Group implies we and they.  Territory implies ours and yours.  Together they form a linked or nested mosaic dividing the species tribally and the land territorially, each tied to or over-laid upon the other.”

That territory and temperament are intimately connected to territory and ecology is exemplified by the temperamental differences between chimpanzees and bonobos.  They are very similar morphologically and very different temperamentally and behaviorally.  Chimpanzees, bonobos and humans are social species with similar size social groups, so the evolution of bonobos from the proto-chimpanzee/bonobo genetic stock is of interest for human evolution from the proto-chimpanzee/human genetic stock.

Occupying similar ecologies, they evolved slightly different morphologies – bonobos are smaller and more gracile – and possess significantly different temperaments and behaviors.  Chimpanzees are male dominant, aggressive, violent, and noisy.  Male sex is driven by female estrous signaling and there is no female-female or male-male sex.  Bonobos are female dominant, more tolerant, quieter, and peaceable.  Male-female sex occurs outside of female estrous signaling.  Female-female sex is common and there is male-male non-penetrant non-orgasmic non-homosexual sexual contact.

The explanation for these differences is to be found in the formation of the Zaire River about 2 million years ago which separated two populations of the proto genetic stock, and chimpanzees and bonobos evolved in significantly different directions under different ecological constraints.  Bonobos occupied the southern forest with a better food supply: survival was easier and less competitive.  It is unknown but entirely possible, that they had less predation pressure in the denser forest, particularly during the time in which they occupied the tree canopy, but also as they increasingly occupied ground level.  Chimpanzees occupy ground level during the day and the tree tops during the night, and some troops now occupy dryer savannah territories with probable higher predation levels and fewer food resources.

There is no identifiable geological barrier that divided humans from our proto-chimpanzee stock.  We can only observe the morphological, temperamental, and behavioral differences at the present time.  As we evolved, we became larger, weaker, fully bipedal and upright, with a smaller gut, hairless, flatter faced, larger brained, more intelligent, with finer control of hand muscles, etc.  Our sexual behaviors are closer to bonobos than to chimpanzees.  Our mating system is primarily serial monogamous pair bonds with occasional extra-pair copulations.  We are very much more communicative and cooperative than either the chimpanzees or bonobos.

Our current understanding is that much of our later evolution occurred on the African savannah.  I did a web search for images of savannah ecologies and saw wide vistas of grass with scattered trees.  It looked like a tough place to live.  We cannot eat grass; we are not herbivores.  We cannot eat leaves, branches or bark; we are not browsers.  We cannot digest cellulose, the most widely available ‘food’ on the savannah.  We eat fruit, but the trees were not heavy with colorful fruit inviting me to eat.14 Outside of the fruits that co-evolved with animals for seed dispersals, plants do not advertise.15

Some of the pictures show dangerous carnivorous predators, best to avoid them.  Other pictures show large herbivores, they look like good food, but a hunt is not always successful, and hunting risks injury or death.  Best to eat mostly plants and occasional meat.  But where is that food?  Nuts and berries are visible but seasonal; nuts need to be stored and carried, and berries have low ‘shelf life.’  Some plants developed fleshy roots, bulbs and corms rich in sugars and starches as their food and water sources during the dry season.  Storage is plants conquest of seasonality and mobility is the animal’s response to seasonality.  Our mobility allows us to prey upon these plant’s storage survival strategies.

These high calory foods, on the one hand, allow for smaller territories, with less time and risk to acquire food.  On the other hand, these foods are patchy, low density and scattered, and those factors necessitate larger territories and greater time and risk.  And we have to dig for them with consequent opportunity costs – digging takes time that could be expended ranging farther for foods easier to procure.

Plants are not obligate food sources for animals.  Outside of some of their fruits, they did not evolve to feed animals.  Indeed, plants may evolve tough skins to deter, spines to injure, and toxins to poison the animals ‘preying’ on them.  A question we must ask of any prospective food is “will it poison me?”  Who will test the prospective food?  Who will eat the berry?  Lives may well have been lost learning what not to eat.  In the process of evaluating new foods, we watch carefully for ‘I ate this and I got sick,’ one trial cause and effect learning.  There is an underlying food fear, basic and intrinsic, in our temperaments.

Cooking destroys some toxins and kills parasites thus making food safer.  It pre-digests food, decreasing digestion time and increasing caloric availability.  Our lower guts are smaller and shorter than the other great apes which eat browse.  We do not eat for hours and digest for even more hours.  The time and energy saved from digestion can be repurposed to other survival activities including exploring, gathering, hunting, transporting, and cooking.  Fire extended our active day into the night and we developed activities to absorb the time: story telling, partying, dancing, wrestling and other competitive activities: play – another temperament.16

We are then, the restless ape.  Predators may be extremely lazy and herbivores need downtime to digest tough vegetation.  But humans are neither lazy predators nor digesting ruminants.  We are instead restless – exploring, and foraging for patchy seasonal resources.  In a circular cause-effect we need a lot of calories to support our brain, the ecology in which we evolve requires a lot of effort to acquire those calories, and we have a physiology and temperament suited to those requirements.

Hairlessness allows for higher metabolic heat rejection than other animals and we can employ persistence (cursorial) hunting techniques, which takes time and energy.17  Hunting provides additional protein and energy which is needed to fuel our greedy brains.  That single organ consumes about 20% of our caloric intake.

The question of how much did early humans hunt has vexed anthropologists for a long time.  The necessity of maintaining our salt balance may suggest an answer.  I have not found any references in the anthropological literature to relict foraging hunter gatherers locating salt.  Salt deficiency disease (hyponatremia) may have been a problem for foraging hunter gatherers on the savannah unless they were successful hunters.

“Early humans may have been particularly prone to sodium depletion as they primarily lived in arid environments that were bereft of sodium and a majority of their diet consisted of plant matter. These environmental conditions provided the selection pressure for the development of a set of physiological mechanisms that would help maintain and replenish sodium stores in humans. ….  It is important to realize that the sensitization of sodium appetite can be conceived of as an adaptive form of simple, non-associative learning that aids animals in maintaining sodium balance when faced with environmental conditions and challenges that threaten body sodium content. When body sodium content is repeatedly depleted it is adaptive for an animal to seek out and ingest greater amounts of salt to help restore sodium balance and to protect against future sodium loss. For example, humans working in hot environments can lose significant quantities of sodium through sweat, and it would be ideal for these individuals to develop a propensity to ingest salty foods to protect and restore sodium balance. However, a negative consequence of sodium appetite sensitization is that it could promote pathological salt intake that may contribute to the development of many disorders including cardiovascular disease.”18

The need for sodium may drive foraging hunter gatherers who depend upon meat and blood for sodium to an increased desire to hunt (or to scavenge).  Herbivores utilize two sodium strategies.  They obtain it from plants, which do not need sodium, but uptake and concentrate it in their structures.  Herbivores eat large quantities of herbage and browse, and they may derive sufficient sodium from plants.  We cannot eat and digest enough plant material to maintain our sodium levels and hunting would be our major strategy.  In a circular cause and effect, cursorial hunting on the hot savannah increases sodium loss due to sweating and this would increase the need for obtaining sodium via hunting.  Herbivores would have been our most common prey, thus passing some of their sodium to us.  Plants growing in low sodium soils may not provide sufficient salt and herbivores locate salt licks to maintain their sodium levels as their secondary strategy.  If salt licks were in our territory, we may have followed them and procured it for ourselves as our secondary strategy also.19  Hunting would remain as our primary sodium strategy, for it simultaneously provides high quality food to fuel our voracious brains.  Carnivory solves two problems at one bite.  Territory and its ecological constraints may drive physiology and temperaments which control behavior.

Humans are, as noted above, a fission-fusion social species.  Diurnal fission for foraging and hunting or just exploring, requires a territory sufficiently rich that journeys for most resources can be performed within the day.  Women gather most of the calories and are frequently burdened with children, so their range may be less.  If they leave infants in the care of another woman, they must return during the day. We return to a temporary base camp with its friends, shelter, and most important, fire.  The base camp is the locus of our group sociality, eating, grooming, telling stories: establishing and maintaining social bonds.  As resources here are depleted, we will move camp to go there, so our overall and seasonal territory is larger than our diurnal territory.

For this, we require navigation, mapping, sense of time and season, alertness to signals of dangers from predators, etc. and activation of appropriate responses.  We were, and still are, ground dwellers, and ground is more dangerous than high in the trees.  From danger are derived courage, adventurousness, and risk tolerance which are individually variable and may be considered to be temperaments.  I have, in the essay on the sentinel, posited that overwatch behaviors – sentinel and warrior – are temperaments, which are individually variable and vary with age.  Older individuals who may no longer be active warriors become sentinels, descrying and calling out danger.

Territory, land and its possession, is a primal value for it holds everything necessary for survival.  Fortunately, our most necessary resource, air, is everywhere and requires no effort to acquire.  Learning the land and mastering its riches, seasons, and dangers requires exploration and experimentation, time and effort.  How to locate and extract its resources is shared and passed through time via the collective memory of the social group, thus increasing our storage capacity and its reliability by distribution among individuals.  Learning what is already known from peers is easier than discovering it oneself and may well be more reliable as collective knowledge is improved over time.  Territory and sociality are thus linked.  Membership in a social group is survival.  The group holds territory.  Territory is survival.  Humans are a social, tribal, and territorial species with mental abilities and temperaments suitable for survival therein.  The potentials and constraints of different ecologies and climates selected for various temperaments and consequent behaviors required to survive.20

Functional Temperament

“…temperament, is a relatively fixed set of mental and emotional attributes that define major elements of personality.  Temperament is an over-all, large scale pattern or tendency such as curious or fearful, credulous or suspicious, wild eyed or reasonable. …. The roots of individual psychology are deep within the sociology of a social species … and temperament, while personal, is sociologically functional – that is, personality in some respects subsumes under sociology – the needs of a social group.  Temperament, while basically individual, is more fundamentally sociological for it governs to a large extent how an individual functions within its group. … Perception of the needs of the group will develop aspects of individual temperament.

“There are functions that must be performed for the survival of a social group, specifically, but not limited to the sentinel descrying danger, the warrior protecting, the artisan making and the story teller explaining.  These and other temperaments, in particular mothering, are positively selected for.”

The contemporary conceptualization within individualistic large-scale civilized – city dwelling – societies is that sociology – social structure – is the summation of individual temperaments, placing the individual at the center.  For small-scale foraging hunter-gatherer social groups, I have inverted the relationships and placed sociology ahead of individual psychology.  The social and survival needs of the group determine the range of individual temperaments and behaviors expressed within it.  Over our long evolutionary social history, I do not think it could be any other way.

The African savannah shaped us as we in turn shaped it.  The requirements of living and functioning in social groups within the demographic dimensions of the Magic Numbers shaped us.  Our morphology and physiology, in particular our lack of both defensive and offensive weapons, hairlessness and large brains, drove or allowed, (whichever evolutionary viewpoint appears to provide the best explanation,) the range of temperaments and consequent behaviors available in the human toolkit.21


I failed to find a good place above for this sentence, so here it is: “Patchy resources select for sharing temperaments.”  And then I had to write a paragraph:

Some time ago I did a web search on chimpanzee food sharing and among the images were the outstretched hand begging for shared food: chimpanzees begging for food – Google Search.  Begging for food, sharing it, and appraising fairness are integral elements in social groups.  If the analysis above of the different ecological conditions of chimpanzees and bonobos is correct, one possible hypothesis is that chimpanzees on the savannah should express more begging and sharing than those who are able to successfully forage independently in richer territories.  We beg and share.  We offer to share.  And we appraise the fairness of sharing.  These are essential social temperaments, of which more in the next essay.

I summarized the evolution of the divergent morphology and temperaments of chimpanzees and bonobos with: “The potentials and constraints of different ecologies and climates selected for various temperaments and consequent behaviors required to survive.”  This sentence expresses conventional evolutionary concepts: the sculptural power of differential survival to select attributes to be forwarded into the future from the variety of those available.  Straight forward evolutionary causation.

 Our evolution is within a web or mesh of factors and the connections between them.  Establishing causality between these factors requires an accurate time line, this has to happen before that for this to cause that.  Temperaments and behaviors do not fossilize, nor do the elements of our physiology and morphology of interest to this story, so we cannot determine a time line for such elements as the loss of ability to synthesize vitamin C, and our loss of hair and increase in sweat glands.  Further, our verbal story telling brains can only do one thing at a time and cannot think or write meshes.  Words in sentences, sentences in paragraphs, and paragraphs in essays are linear, making them good tools for expressing linear causality and poor tools for the study of a mesh of evolutionary factors.  So, I do not assert causality among most of the operative factors, only connections.

Meshes reduce the possibility of straight forward evolutionary ‘survival’ and ‘fitness’ arguments.  Our inability to synthesize vitamin C, an essential vitamin, is an evolutionary puzzle.  Several hypotheses have been advanced, most of them based upon our ability to forage for it rather than, like almost other animals, to make it for themselves.  So far, it does not appear to be a fitness advantage, indeed, it may be a fitness disadvantage depending on the resources of the territory.  I suggest that it was a genetic change of unknown cause for which we are able to compensate.  Not everything in our evolutionary history can be construed in terms of fitness and survival.  Some factors may indeed tend to decrease fitness and survival, but we have adapted to them over time, and in the case of vitamin C, by a technological rather than a biological adaptation.  We learned to eat more of certain foods and eventually to synthesize vitamin C.  Scurvy in the Western world is now virtually unknown.  We have survived despite fitness and survival disadvantages.

The problem of salt physiology on the African savannah is an example of a mesh.  The more research I did, the more complex it became.  These resources are suggested:

The web search: how do herbivores get salt – Google Search

And these sources:

The seventh macronutrient: how sodium shortfall ramifies through populations, food webs and ecosystems – Kaspari – 2020 – Ecology Letters – Wiley Online Library

Carnivores — WHAT THE HEALTH (

I’ll suggest this interesting SWAG: salt licks would be used by any and all herbivores, and would have been contaminated with urine and feces.  Disgust is a major human temperament.  If we were to be disgusted at the sanitary conditions at a salt lick, would we have shunned the strategy of obtaining salt for ourselves from this source and thus depend primarily or even exclusively on hunting?

The choice of where in our evolutionary mesh to begin this essay was then a matter of some consideration.   I have assumed that territory and climate are constant and that we have at least a reasonable adaptation to them.  This essay has set out, upon those constant factors, our baseline demographics, social group size, and relevant temperaments.  The next essay will continue to develop baseline social temperaments, and after that all hell breaks loose as those constant factors change dramatically.

I posted the first essay on social theory three years ago, and I have returned to the topic several times over those years.  These essays are mind prints leaving tracks of where I have been and pointing to where I am going.  They are sorta like chapters published intermittently and not yet finished.  I cannot expect a reader to remember what I wrote so long ago, so here are the links to the most important social system essays:

What is a Social Species? – Carl Wilson (

How to Make a Social Species – Carl Wilson (

Tribe and Territory – Carl Wilson (

The Sentinel, the Warrior, and the Social Group – Carl Wilson (

Functional Social System Sociology – Carl Wilson (

Functional Social System Sociology, Part 2 – Carl Wilson (

The four Evolutionary Morality essays:

From Utilitarianism to an Evolutionary Morality: We Were Moral Before We Were Civilized – Carl Wilson (

Evolutionary Sexual Morality: From Sex Drive to the Pair Bond – Carl Wilson (

Are Humans a Monogamous Species? – Carl Wilson (

Into the Ring of Fire – Carl Wilson (

Robin Dunbar’s paper on the social brain hypothesis:

Social Brain Hypothesis and Human Evolution | Oxford Research Encyclopedia of Psychology

I found this source after I had completed this essay.  I extract from it this statement of the relationship between our risk of predation and the exigencies of foraging, and our social brain:

”…primates solve the predation problem indirectly by first solving the problem of creating coherent, stable, coordinated social groups. The issue (of brain size and complexity, ed.) thus comes down to the task demands of foraging versus social coordination.”

A social group has friends to provide extra hands for gathering and hunting during the day, alloparents for child care and eyes and ears during the night.  We communicate and cooperate, sharing knowledge, food, and personal and group bonds among those friends.  Specific temperaments and behaviors are required to build, maintain and behave within our “…coherent, stable, coordinated social groups.

  1. Brian Fagan, anthropologist, and author. 

  2. See links at the end of Afterwords, below. 

  3. Unattributed quotes are from previous essays.  I have listed the essays in the Afterwords. 

  4. Current political events, circa late 2020 and early 2021, display the danger sentinel and warrior protective social temperaments and behaviors consequent to the telling of fear stories. 

  5. At least up to now.  How far into the future remains unknown. 

  6. While we now flock into cities, we are not a flocking animal. 

  7. Dunbar’s number – Wikipedia 

  8. Specifically the size of the neo-cortex for which I have used the term ‘neo-brain’ in previous essays. 

  9. Dunbar did not attach his name to the upper limit.  That was conferred upon him by his peers in honor of his explication of the number. 

  10. Burden is a technical term from electro-mechanical control systems.  Each device consumes a specific amount of electrical power – its burden.  This concept, ‘ported over’ to human brain function, means that different activities require more or less brain processing power and time. 

  11. In recent years management theory has used these numbers to develop guidelines for the number of individuals on a specific project.  Computer game designers have also considered these numbers in the design of interactive games. 

  12. Minimum viable population – Wikipedia 

  13. There is male transfer, but it is generally because the male failed to fit in and left voluntarily, or was forced out. 

  14. Plants Can’t Talk. But Some Fruits Say ‘Eat Me’ to Animals. – The New York Times (  

  15. Except to pollinators. 

  16. This would be a fine place to divagate into neotony and play, but with an effort I resist the impulse.  Compared to other animals we retain elements of infancy and youth into age such as play, curiosity, adventure, goofing around, imagination, etc.  We are the neotonic ape. 

  17. Which is not available to chimpanzees, bonobos, and in particular to gorillas. 

  18. The biopsychology of salt hunger and sodium deficiency ( 

  19. Cf. ‘Salt licks’ in the Afterwords for an interesting speculation on human temperaments. 

  20. Cf. Afterwords, below for a review of this sentence. 

  21. The selection of best explanation is frequently a function of individual’s temperament and training.