The earliest primitive people did not have enough minds, such as the early ape man, 3.77 million to 1.8 million years ago, the life must be very difficult, not only did not find the existence of fire, but also in a period of climate and environmental degradation, the situation is not too much to be endangered, until the evolution to the stage of Homo sapiens, the situation began to improve.
The following are tandem from community, brain volume, lactation, the cause of infant crying, and many other aspects to try to illustrate the possible survival of primitive human babies.
Students who are not interested in technical details can skip to the "3, the length of pregnancy after evolution" or "4, the reasons why babies cry", because these two chapters are more understandable and look less boring.
The use of fire occurs in such a long period of time between about 1.6 million and 150,000 years ago, that is to say, earlier primitive people (such as early apes, Australopithecus), the external world to face is actually an extremely complex, terrifying existence, the fate of infants and in the wild to see birds and antelopes waiting to be fed in the wild is roughly the same, at any time may encounter fierce predators, life is naturally very difficult. At that time, there was no community building capacity, and there was not enough mind, and any crying could lead to the disaster of killing, and even because of the low mind, it could trigger suicidal reckless behavior.
In the era without fire, the early ape people who had a difficult life, living on individuals, collecting plants in pairs and hunting small and medium-sized animals, began to have three large-scale aggregation quantitative constants - 5 (family life), 15 (cave aggregation), and 45 (community size), which are the three key constants of the social scale that the social brain can support in the evolution of the social brain.
With the increase in the number of gatherings, there was a large-scale community co-construction force, and only then began to increase the mind, and there was a gradually obvious division of labor and cooperation, including progressive types such as manufacturing tools, and developed in the direction of late ape man (Homo erectus, 150 to 200,000 years ago), early Homo sapiens (more than 200,000 years ago to 50,000 years ago), and late Homo sapiens (new people, 50,000 to 10,000 years ago).
However, without the emergence of hominids gathered on a community scale, it is impossible to evolve brain capacity and mental capacity that can maintain high-quality survival rates in the face of the challenges of unknown environments. This means that if the size of the community cannot be developed, it is basically dependent on the sky to eat, rely on luck and experience to eat, and the quality of life of the baby will naturally not be high.
There are three factors related to the evolution of the ape-man and primate brains (from The Evolution of the Social Brain, vol. 317, pp. 1344–1347).
Why it is said that brain volume is related to community, because the average size of the great ape community will increase with the rise of the "new brain index" (the new brain index is the ratio of the volume of the prefrontal lobe to the total volume of the rest of the brain region after deducting the prefrontal lobe), that is, gathering to produce complex survival behaviors such as socialization, reassurance, sharing, and material exchange, living together every day, long-term generation after generation of reproduction, brain capacity may appear rapid evolution possibility.
In the figure above, there are three major factors in the evolution of the brains of apes and primates, which are more like constraints of evolution than like the driving variables of evolution:
1. Foraging range 2. Daily behavior 3. The size of the prefrontal lobe (neocortex) of the brain.
The core part of the diagram above is the "basal metabolic rate" (BMR), which has three functions:
1. The amount of brain necessary to maintain the necessary level of nutrition and metabolism (first determined by the size of the body), which interacts with the life span of the individual (also affected by the size of the body). 2. Interaction between body size and food intake (determined by basal metabolic level). 3) Body size and food intake (through the daily reachable range) determine daily behavior and the extent of foraging or home, and this range depends on the size of the group of individuals with enough trust.
Nor is the growth of the neocortex (the part of the prefrontal lobe that has only expanded and formed in the last 500,000 or even 50,000 years) because it must meet and adapt to three external constraints:
1. External threats 2. Group size 3. The expansion of the new cerebral cortex allowed by brain volume
In addition, the earliest communities were largely made up of blood-related ape-men. Because blood kinship makes apes feel safer and more satisfied, and more willing to share the fruits of labor, especially when faced with crisis choices, blood kinship is more likely to trigger inner trust and sacrifice.
Relationship between community size and cerebral neocortex, with mean population sizes ranging from 100 to 200 (from a review article published in the Annals of Anthropology in 2003)
Due to the changes in the community and the external natural environment, the gradual formation of a larger group-sized community, the evolution of brain volume, and finally make it possible to effectively accumulate in a shorter period of time, more group members can successfully cope with the knowledge stock under the uncertainty of the external environment, thereby reducing the overall demand for individual intelligence, and the survival rate of human beings after the division of labor begins to be greatly improved.
In terms of brain volume, the second half of the late ape man (about 500,000 years) and the early stage of the late Homo sapiens (50,000 years), that is, 50 to 50,000 years ago, the quality of life of the baby began to gradually improve significantly, because the ape man began to produce a mind, formed a certain wisdom precipitation, and slowly had a huge division of labor and cooperation power of the community.
Studies of all mammals have found that the length of pregnancy is related to the development of brain volume.
Based on regularities found in other mammals, brain volumes like ours take up to 21 months to match during pregnancy. But we know that a woman's pregnancy cycle is actually only 9 months.
The reason looks like this:
Millions of years ago, our ancestors decided to have bigger brains, and even better, they decided to walk upright. This allowed us to evolve a unique bowl-shaped pelvis, which differs from the slender pelvis of monkeys and apes. This bowl-shaped pelvis better balances the head and trunk, allowing us to walk better, especially when our brains have expanded tremendously, starting with homo sapiens, the first generation of human beings, and we are finally able to walk in meteoric strides, that is, to be able to make long journeys and constantly migrate, rather than staying in a limited area (as opposed to monkeys). But the inevitable problem with evolution is that we can't get perfect ergonomics. The ability to travel long distances requires sacrifice, i.e., our spines are not strong enough, and the end result of evolution is to leave behind lower spines that are convenient for "walking", not for the vertebrae and pelvis that are more suitable for fertility. Millions of years later, when the offspring of our ancestors decided to massively expand their brain capacity, they ran into a problem: the bowl-shaped pelvis greatly reduced the birth canal, and the size of the baby's brain became the limiting factor for fertility. At this point, humans have basically no choice. Of course, we can also backfire and abandon the idea of evolving a larger brain. But if that were the case, we wouldn't have any evolution, you know, at that time, the global climate and the natural environment had changed dramatically, and to survive, we had to migrate and deal with new environmental changes, and if we didn't move forward, it meant falling into a more difficult ecology, just like other struggling great apes, whose numbers had fallen to the point of extinction at that time. In order to survive, we had to change and adapt to this new ecological epoch. The large-capacity brain is the key to this change, and without the evolution of this brain volume, no other changes can happen, and the miracle is about to come out. Eventually, our ancestors came up with a solution: drastically reducing the time it took for the mother to conceive, from the 21 months it originally took, to the current 9 months. However, the risks are obvious, and if we give birth to a baby whose brain is only half developed, then the baby will be very dangerous. In contrast, newborns in monkeys and apes can bounce around alive for a few days after birth, while human children can reach this level of walking for a full year.
Compared to newborns in monkeys and apes, human babies are life-threatening even when born at term. That's why they are always very painful to be born in a state of immaturity. Studies have found that immature infants have a very high rate of developmental disabilities, including frequent illness and poor academic performance. Of course, this is not to say that this is true for every child born non-term, but rather that this risk is more likely to occur.
In the first year after birth, both primitive and normal human babies need meticulous care and affection.
And this kind of meticulous care and love is very energy-consuming for parents, even more tiring than labor, so children will win love through a variety of cute-looking, cute behaviors, especially when they are hungry and sick, non-stop crying can cause more attention and love.
Of course, this situation also brings a whole new set of problems. From Mom's point of view, this is the price given to her husband. At this time, there are two options: either make sure the child looks like the husband, partially or completely, or make the child look different from any other dad. In fact, human beings seem to be like this. Unlike adults, human newborns initially look similar. In fact, all children are born with blue eyes before they turn brown or green. This requires the father to guess who is the child. If there is no point on the child's face that can see the blood margin marks, it does not mean anything, and there are still many "ways and reasons" around the child to comfort the baby's father.
1. Primitive humans 500,000 years ago
That is, for most of the early ape-man period, and during the Tugan primitive man, which is about 6 million years old, the quality of life was extremely low, and crying would probably have a catastrophic effect, which may be caused by external crises, or caused by the reckless and violent and irritable behavior of the primitive people themselves, because the mind is not sound enough.
The early primitive mind is not yet mature, in neuroanatomy, apes can only manage the second order of intentionality (referring to mental intelligence, monkeys are the first order, only know the thinking of the self, the second order can reflect the psychological conditions of others, equivalent to the thinking of human five-year-old children, normal humans are the fourth order, the adult limit is the fifth order), and do not have complete moral judgment ability, so there is a possibility of abandonment, manslaughter, and even stupidity to trigger suicide. As the brain's neocortex increases dramatically, computing power begins to increase, and this process may begin to emerge truly introspective and logical, allowing individuals to process binary levels of relationships one by one, or to think recursively about relationships between individuals. It was only then that religious and moral systems began to take shape. Regarding the true leap-forward increase in frontal lobe volume, fossil evidence from humans suggests that this is likely to have occurred very late in human history. But almost certainly, it only started to appear about 500,000 years ago.
2. Primitive humans between 500,000 and 50,000 years
Including the late ape man living 150 to 200,000 years ago, Homo erectus, and the end of the early Homo sapiens living more than 200,000 years ago to 50,000 years ago, their brain volume, brain neocortex is slowly but accelerating, introspection, logic, morality, etc. began to initially awaken and enhance, the quality of life of the baby also gradually improved, but this process is long and very slow, is a cocoon into a butterfly "weight-bearing time", similar to the "Song of Ice and Fire" in Arya Stark, load-bearing sneaking.
"Weak" Arya Stark
3. Primitive humans from 50,000 to 10,000 years ago
That is, in the late Homo sapiens stage, especially 10,000 years ago, as primitive people really lived in villages, a large-scale social division of labor and a stable living environment began to appear, knowledge and experience began to be shared and disseminated in a more efficient form, and the mind, morality, faith, etc. began to awaken at an accelerated pace, and a preliminary mature social culture was produced.
With the rise of consciousness, human beings have entered the Mesolithic Age in the early Holocene (gradually began about 15,000 to 10,000 years ago and ended about 8,000 years ago) and the Neolithic Age (gradually began about 10,000 to 5,000 years ago and ended two thousand years ago), when the crying of babies ushered in a truly spring-like warm care and care, and human beings really opened a new era of conquest from this time.
To add, with regard to matriarchal societies: In the late Paleolithic period (beginning about 10,000 years ago), a gradually growing matriarchal clan system emerged, due to the gradual rise of the mind of the late Homo sapiens, which brought prosperity and maturity of civilization and community environments, but hunting remained unstable and meant casualties, until women invented primitive agriculture and livestock rearing, solved the problem of food, began to be widely respected in the economic life of families and societies, and gradually gained a central dominance. However, men still undertake part of the hunting, fishing, defense and other tasks, the food problem in the matriarchal society is no longer a survival problem, in this more stable matriarchal and good social environment, human beings have developed a brain capacity that is not inferior to today,as well as complex language, sophisticated handicrafts, including the initial maturity of early culture and beliefs. But with the development of productive forces, the demand for labor force is growing, the labor productivity of the matrilineal group and the combat effectiveness of the group are not as good as the patrilineal group, the matrilineal society is suitable for appearing in the period of "primitive social productivity and low technology", after entering the period of agricultural civilization, in fact, the patrilineal group is gradually beginning to exert force, and with the emergence of large-scale conflicts and wars caused by productivity and desire, the patrilineal group has gradually replaced other matrilineal groups and regained the core position of the economic foundation and social system. There was even a period when women were reduced to slavery, but in any case, human beings have matured mentally and in quality of life, and the cries of babies will be guarded by guardians (even aunts and grandmothers).