Orientation
What is culture good for? Why do we have it at all? Why not continue to transmit information through genetic means? What types of conditions existed that catalyzed selective pressure for culture? What are the dangers of having culture and what are the benefits for some organisms that outweigh the risks? John Tyler Bonner’s great book The Evolution of Culture in Animals assumes that biological evolution is a necessary condition for the emergence of culture. Culture is not freely constructed. It must have biological equipment as a foundation. Nevertheless, culture is not simply the creature of biology. Culture can change the ecology and the ecology in turn controls the direction of the selection of genes.
But what do we mean by culture? Anthropologists have given us many definitions but taking the long view that Bonner does allows us to claim a simpler definition. Culture is the system of passing on information primarily by behavioral and symbolic means rather than genetic means. The emergence of the brain in turn is a necessary mediator but not sufficient condition for culture. In other words, without a brain there is no culture but many other animals have a brain but do not have culture. The brain allowed organisms to learn, to teach and to increase the flexibility of responses to the point that responses can not only be passed on but invented.
Genetic vs Cultural Evolution
In genetic evolution genes pass on information containing molecules from one individual to another through fertilization. In cultural evolution information is passed on through language not through fertilization but through learning and teaching. In genetic evolution the number of offspring is the number of times it has been able to transmit genetic information across generations. This can occur repeatedly between two individuals (monogamy) or through many individuals (polygamy). In cultural evolution information can be transmitted from one individual to another or between many individuals. In biological evolution changes are slow. Most mutations are unfavorable and when one favorable mutation occurs it takes many life cycles—hundreds of years for a new gene to be present in a significant number of individuals. In cultural evolution, especially today, changes can occur within a single generation.
In order to better understand the emergence of culture in animals we need some preliminary definitions from biology. According to Bonner the phenotype is the sum of all the visible structures that compose the organism. This includes both the body and its behavior. The genotype is the (invisible to the naked eye) collection of genes that specifies the characteristics of the phenotype. As Dawkins might say the phenotype is the survival machine of the genes. The phenotype mediates the relationship between genes on the one hand and ecology on the other. The most effective ways genes can perpetuate themselves is by having closely related survival mechanisms (families) that house them and are helpful and altruistic with one another. Genes are not selfish as individual molecules but as a class of identical copies capable of replication in successive generations. The more copies, the more numerous they are in next generation The genome is the assembly of genes of any one individual organism minus the brain. The brain carries whatever behavioral information exists and is housed in the phenotype.
Why Evolve to Multicellular Organisms?
In order to understand these complex processes that lead to culture in animals we must go deep into organic evolution and build our way forward. To begin with, why do we have multicellular organisms at all? After all, there are far more microbes than multicellular organisms and many are successful. However, under some conditions genes have a better chance for survival if they are carried by larger organisms. Why? If the rate of change in the ecology increases, they can trade off competing with smaller organisms for the exploration of new environments. In other words, the energy expended in competition in a familiar environment is traded for less competition and more exploration, a dangerous but sometimes necessary choice.
Who Needs Brains?
What does having a brain do for organisms? Why have them at all? Or why do some organisms have brains while others do not? The reason for having a brain is a further development of the same reasons for organisms becoming multicellular. When ecologies change quickly brains are useful because they can make decisions faster than genomes. In environments which change slowly, brains are unnecessary because the slow rate of genetic change on organisms is satisfactory and the cost of producing brains is too high.
The genome produces rigid predisposition patterns. In a reflex as little as one neuron may be involved, and the impulse spreads from one branch of the nerve axon to another. The next step beyond this involves two neurons, a sensory and a motor neuron. But neurons can excite or inhibit therefore having one or two possible results instead of just one. This means that there is now a division between what comes in (the senses) and what response is taken (motor). Input can be expanded or reduced instead of passively taken in. Outpoint can also be expanded or inhibited. In some smaller celled organisms there are simple brains, but these are decentralized. In the complex brain of larger organisms the brain is more centralized. One reason Bonner gives for the centralization of the brain is mechanical efficiency.
“If nervous system of an animal is to increase, the larger size and needs more neurons to control its parts or because it is advantageous to sense the environment more critically …centralization is probably the most effective method to adopt”
If the nervous system of an animal is to increase—either because the animal is evolving to a larger size and needs more neurons to control its parts, or because sensing the environment more critically is advantageous—centralization (forming a brain or a ganglion) is the most effective method to adopt.
This centralization leads to an increasing connection between neurons to occur over shorter routes and resulting in a quicker response which is more critical and creative. This includes behaviors such as more choices for which resources may choose from and the capacity to expand to new environments.
For example, let us say that as an ecological setting becomes colder, a genetic response is the appearance of genetic variants which may result in fur blubber. But in humans, the response to low temperature in a human society is to make clothing and put the clothing on. If the temperature has gotten colder gradually, the genetic strategy works fine and there is no need for a brain. In fact, it is too costly. However, if a drop in temperature is sudden, those organisms using a genetic strategy will die whereas those human societies that can make and use clothes have a chance at survival. Under these conditions it pays to have a brain. In other words, the growth of organizational complexity in organisms is a response to:
- quickly changing environment and
- adaptation to complex forms of social organization (as we shall see).
What the genome and the brain have in common is: they are both physical bodies; they both take and store information; and they give out instructions and alter information. They are at the same time symbiotic. While the brain evolves out of the genome as an efficient survival machine to perpetrate genes, the brain can also perform behavior that goes beyond the genes as we shall see.
Origins of Genome-Brain Dichotomy
The roots of the genome-brain split has to do the costs and benefits of slow as opposed to quick responses. The major differences between biological and cultural evolution has to do with the quality and speed of response necessary to survive. The hormonal response to any environmental change is conspicuously slower than a nervous response. Following Haldane, Bonner identifies five kinds of time that biological processes take:
- molecular—fast—less than one second;
- physiological—transmission of an impulse along a nerve or contraction of a muscle—one second to one hour;
- developmental—life cycle varies from 50 minutes—for bacteria to 70 years;
- historical- a number of generations beyond an individual but too short to produce major genetic changes and
- evolutionary/genetic – 10,000 years to produce a new species
These types of time overlap: the developmental lives of individuals are like tributaries which flow into the river of various historical periods. The river of historical time flows into the ocean of evolutionary processes. The relationship between speed and size is interesting. According to Bonner, at the microlevel, from electrons to large molecules speed of motion decreases with size. However, from larger organisms through to celestial bodies speed increases with size. These two extremes meet up where a small object is too large to move by physical forces. Brownian motion no longer has the ability to budge the particles because they are too big. This is the point of minimum size for living organisms.
Non-motility and Motility in Bacteria
According to Bonner, bacteria motility is a primitive forerunner of nervous coordination and brains. When the organism can’t move it is completely dependent on where it is—in a favorable location it thrives and in a bad location it perishes. In the case of bacteria if non-motile is capable of spore formation they can avoid destruction by:
- becoming dormant or
- if they are transported from one place to another by chance).
One reason for bacteria to remain non motile is if they live in an aquatic environment where there are currents which bring the nutrient to the cells. If the rate of environmental change in nature is slow, not moving and competing with other organisms is a better bet than being mobile and developing a whole new anatomy that goes with it which allows it to move. In a fast response an organism moves away from an undesirable location to a desirable one.
Motile vs Nonmotile Animals and Plants
Trees and shrubs are non-motile and rely on seed dispersal for their continued existence. This includes by wind, water or animals. Plants also are sustained by photosynthesis if they can stay in the sunlight.
“For plants with separate male and female individuals and for plants requiring cross-fertilization even though one plant has both male and female parts of the flower, the male pollen is brought to the female stigma by wind, insects, birds or bats.” (pg. 73)”
For a large photosynthetic animal, the constraints of their size would not allow them to acquire enough energy from the sun to do much moving. An animal would have to wait for the next sunny day to recharge. This drives photosynthetic animals to become more motile. Motile animals disperse by their own locomotion, including foraging, chasing prey, running away from predators, finding mates, moving away from inhospitable weather. Under conditions where food is scarce for animals, nature selects for two new features: cunning and discrimination. When food is scarce cunning helps so that hard to find food may be trapped. The second skill is the attraction to meat which gives greater concentration of energy in large morsels. Both cunning and meat eating invite the cultivation of a brain.
It would be too linear to assume that once the locomotion strategy occurs all animals remain motile. Some return to a non-motile state. Bonner gives the examples of adult sponges, barnacles and some mollusks—mussels or oysters. But why revert? Bonner argues that if the organism is going to filter-feed in an area where there is a current, as with bivalves and ascidians, it would be a waste of energy to rush around if the current will automatically bring food to the animal.
Non-Human Animal Societies
Earlier we defined culture as the system of passing on information primarily by behavioral or symbolic, rather than genetic means. We said that the emergence of the brain was a necessary but not sufficient condition for culture. But what is the place of society in the relationship to culture and the brain. Do you need a brain to have a society? Do you need a society to have a brain? Do you need a society to have culture? Do you need a culture to have a society? How do all these interact? What is a society, anyway? Bonner’s brief answers are:
- you do not need a brain to have a society—bees;
- you need a society as a foundation of culture. Societies are necessary but not sufficient conditions for culture and
- there are societies without cultures, but there are not cultures without societies.
A weak definition of a society is a cohesive group of intercommunicating individuals of the same species. Seen in this light there are animal societies with various levels of a division of labor, sharing of food and nurturing that still pass down information genetically rather than culturally. Social insects are one of the most extreme cases of social organization with a biological basis. Here is a very rigid division of labor—social complexity-without their beyond any propensity of culture. This might be compared to the social organization of apes, which is loose, yet they have far more cultural ingredients. It is even possible for organisms to not have a brain and yet have a society.
Adaptive Advantage of Being Social
But why be social at all? What are its adaptative advantages? Being social allows organisms to:
- preserve their genes through kin selection. The organism is more effective by forming a society;
- closely related organisms have genes in common and through cooperation they increase their chances of preserving those genes for subsequent generations and
- communal task selection by communal activity certain tasks can be performed by a group that would be impossible to achieve as separate individuals. However, among some species it doesn’t pay to be social. Bonner gives an example of the Indian tigers and the South American jaguars who hunt alone because stealth is needed. If they hunted in packs they would have more difficulty stalking unobserved. In these species even kin selection is not enough to counteract the positive selection for noncooperative hunting.
But stealth alone is not the determining factor in being social. Among social bacteria, social amoebae and many fungi stealth is needed but together they are important for effective dispersal. Additional factors keep them together when the food supply is patchy (as opposed to concentrated) and if whether there is a constant threat. Whether birds are solitary or in flocks also depends on whether the food is distributed in patches or whether it is evenly distributed. Under patchy conditions they are more social and if resources are evenly distributed, they are more solitary.
- Modification of the ecology—beavers build dams; birds construct nests. The modification of the environment allows more control over what becomes of them.
Primitive Social Forms
Our general association with societies is that individual organisms of a species that are not physically attached when they come together. However, they can be physically attached. For example, cellular slime molds amoebae that feed as separate individuals then aggregate by chemotaxis to form a multicellular mass. They are separate cells at one moment and a multicellular organism the next. Individual bacteria cells feed in a swarm, conquering large prey individual bacteria they could not digest as separate cells. There are two castes:
- spores are reproductive caste and
- stalk cells are workers who do not propagate.
Social insects
In higher invertebrates there are new qualities that make them more of a society such as:
- cooperation between individuals in the colony not just in feeding but in taking care of their brood;
- a division of labor connected with reproduction—sterile castes in the colony;
- overlap of at least two generations of individuals in the colony so that offspring will assist their parents at some moment in their existence and
- a temporal or age difference between workers is used as a means of a division of labor. Among honey bees young workers stay in the hive and attend to housekeeping and take care of the brood. As the workers age they become foragers.
If an insect society has all four characteristics they are considered by E.O. Wilson to be “eusocial”. This includes ants, bees, wasps and termites. A big part of the life of social insects that is genetically determined is the ability to achieve different sizes and shapes. However, what is not determined by genes is which specific individual became queen or different kinds of workers. This is determined by the behavioral dominance hierarchy; the balance of pheromones exchanged between individuals or variable success in competition for food. Therefore, the immediate use of caste determination is nongenetic
But why is caste control achieved through behavior and chemicals rather than genes? The former provide a way to reach a balance in the division of labor. Rather than a rigid program, increased flexibility allows a fallback strategy under crisis circumstances. For instance, if an accident or a war were to eliminate the majority of soldiers in a termite colony, the ratio of soldiers to workers could be restored. There is some teaching and learning among social insects but it is rigid compared to mammals.
Social Vertebrates: Birds and Mammals
Because birds and mammals have larger brains, their behavioral possibilities are wider. They can perform a greater variety of tasks and they do so rapidly to accommodate both immediate and sudden needs. In social vertebrates such as birds and mammals social organization expands to include mutual protection, effective feeding, mating, infant care and migration. In order to perform the social structure expands beyond the family. There is little in the mammal world comparable to the morphology of insect casts. Whether there is dominance in a social group, according to Bonner, depends on how much competition there is for food and the presence or absence of predators:
The life of a baboon on the savanna is much more precarious than forest life. Not only are there leopards, and other…predators, but food can be scarce during periods of drought. For howler monkeys, relatively safe up in the canopy in a region of the world where there is little seasonal change and ample supply of leaves and fruit there seems to be small pressure. (source?)
The social division of labor can be seen in wolf hunting in which the pack ambush or outflank a large prey animal—caribou or mountain sheep. Among the hamadryas baboons of Africa the band is a feeding unit and the troop is a unit of protection against predators of the night. When migrating much social behavior is connected to territorial defense. For instance, when red deer are fleeing, they are organized into patterns with the leader in the front and the second in command in the rear, guarding the back.
From Learning to Teaching
What is the differences in the processes and skills that go from social learning to teaching something to someone else? At the extreme ends of the spectrum of teaching is simple imitation on one hand and complex instruction on the other. All social learning differs from communication. The evolution of communication is a movement from emitting of chemical signals to chemical and tactile signals and then to audio visual signals. The most basic form of communication involves the analysis of a signal and the immediate response to it. Even the most basic forms of social learning involve something more that. Here a signal emitted is specifically designed to alter the behavior of another.
At the base of all behavior rooted in genetics are predispositions or instincts. Here the entire behavioral act is directly inherited and has a fixed action pattern in their orientation to light. They can fly toward the light or move away from it. The basic song pattern of birds is inherited. In many organisms a combination of instinct and learning is best. In the case of birds while the basic song pattern is inherited, improvements in the song occur through trial and error by the birds hearing themselves sing and listening to mature birds sing.
In the twilight of learning stands habituation and sensitization. In habituation there is a change of behavior which occurs by repeated identical stimuli. In habituation there is a lessening of a response based on repeated trials. In the case of sensitizing, a repeated strong stimulus builds up in the individual until it departs. The most basic form of learning is imitation which involves learning without any teaching involved. Slow learning occurs through imprinting. Here, learning takes place only within a restricted youthful period. The stimulus received afterward is ignored. On some occasions rapid learning takes place. An example is a bird avoiding a distasteful insect or a confrontation with a dangerous predator.
Types of teaching
The most primitive kind of teaching is self-teaching. This is where birds change their songs as they hear them or monkeys that learn how to make great leaps through the trees by long practice. In simple teaching an organism learns by imitating the model. In human societies this is an apprenticeship. Here no special information is communicated. In complex teaching the information is not simply imitated but is acted upon. A student receives a set of instructions but the student doesn’t mimic the instructions, they act on them. The results of their action is a lesson.
Imitation
It somehow appears self-evident that all creatures could imitate each other. But according to Bonner they do not. This is one of the ways that invertebrates are distinguished from vertebrates. It is only possible to give instructions when the instructor and their pupils have an inborn, innate ability to give and receive messages. Among bees some learning takes place but there are a limited number of instructions they can transmit. Among honey bees in search of food the scout dances to indicate the source of food. The slower the dance the greater the distance is the from the source. A dance straight-up means towards the sun. A dance straight down means away from the sun. The instructions are specific, precise and rigid.
Bees do not learn from other bees. They have a code for distance and direction but this is inherited. What flexibility exists lies entirely within the confines of questions of distance and direction. A scout bee has no way of telling the other bees anything about the color of the flowers, their shape and size. If anything unexpected happens it has no way of communicating it. For example if flowers are on a horse drawn cart that is slowly moving west, bees cannot communicate the complexity of this context.
The adaptive advantages of imitation are:
- In parental care it is advantageous for the parent in its effort to contribute genes to future generations to model adaptive behavior rather than the offspring reinventing the wheel.
- It is advantageous for the offspring to protect themselves and copy adaptive behavior not only of parents but of other adults since they have mastered the survival skill.
- If imitation can be improved by parents reinforcing the trial and error process, that is advantageous.
Besides using direct signals we can also teach indirectly by using artifacts. Bonner points out animals can leave artifact messages which would be instructive by way of leaving a trail. Ants leave trail substances that they secrete from one of their many glands. The ant that follows discovers only that another ant has been there and it instinctively runs along the trail. This is a signal rather than a lesson. In the case of human culture our teaching artifacts involve writing, tape recorders and television where lessons can be drawn.
Evolution of Flexible Responses: Genome Flexibility
In the last sections we’ve focused on how learning and teaching led to the accumulation of more meaningful information. In this section we return to the relationship between the genome and the brain in how it relates to the evolution of behavioral responses, from rigidity to flexibility.
Let us begin with the two extreme poles. In genetic evolution the most rigid behavior begins with asexual, vegetative or parthenogenetic reproduction in which there is no variation. Then there is asexual reproduction with mutation as ones finds in bacteria. This leads to behavior which is relatively rigid. These involve either reflexes (in which only one response is possible) or primitive forms of behavior (in which two choices are possible). There is no true learning which takes place. There is either habituation or sensitization at best. Both of these responses are adaptive in slowly changing ecologies.
As the environment undergoes more rapid change sexual organisms emerge in which there is now both mutation and recombination. This variation allows for the invention of new survival machines which can a) manage unexplored environments, or b) cope with changing environments. In circumstances in which the entire ecology may be changing, sexuality is a good strategy.
In sum, genetic flexibility ranges from asexuality to sexuality. At the extreme end, while cultural evolution is not lawless, as a result of individual experience information which is not genetically inherited can be passed on through learning and teaching. Innovation and inventions take place which have no direct connection with genetics. Multiple behaviors are possible.
Evolution of Flexible Responses: Genome and Brain Flexibility
Ernst Mayr identifies the conditions under which it is an advantage to have a single response and the conditions under which multiple behaviors work better. Single responses involve behavior between animals of the same or different species (these involve communication). This is communication which is ritualized relations with the same species such as courtship among fish, insects and birds, aggressive displays and parent-child relations. With other species these include prey-predator relations which can also involve both single and multiple-choice responses. As an example birds either flying away from a predator or attacking a predator by mobbing.
Conditions for multiple actions involve adapting to the overall ecology (having nothing to do with communication). This includes choice of food or habitat selection. Single responses go with more predictable environments and multiple behaviors go best with unpredictable environments. The appearance of culture emerged as a new niche that arose from the experimentation of animals with multiple choice behavior. The last form of flexibility involves various forms of adaptation based on differences in mating strategies. These include monogamy, polyandrous and polygamous mating.
Before turning to the early beginnings of culture, here is a summary in chart form of the differences between the genome and the brain. Included are a few differences that are not covered in this article.
Table 1 Comparison of the Genome to the Brain
| Genome | Category of Comparison | Brain |
| Produces the structure of the brain | Which came first? | Brain is the product of genes |
| Contains all genetic information of an individual genotype | What kind of information? | Contains all behavioral or symbolic information as part of the phenotype |
| Makes genes | Lowest unit of operation | Makes society and culture |
| Process of gene replication. It builds proteins required to build and rebuild organisms over the life cycle |
What is processed? | Movements and cognition |
| In DNA —makes RNA -proteins | Where is information coded? | Information signals from the sensory systems and motor systems |
| Passes information containing molecules by fertilization from one generation to another | How is information passed on? | Passes information through language in tools through learning and teaching |
| Is responsible for rigid predisposition due to slow changing ecology | How structured or how flexible? | New behavior patterns from older behavior in reaction to a rapidly changing environment |
| Reflex, one neuron—Steady input and passive | How many neurons and what is the nature of input? | Two neurons, sensory and motor Input can be expanded or reduced |
| Simple brain, decentralized Less critically necessary for ecology for smaller organisms |
Kind of brain? | Complex, centralized need is more critical for ecology for larger organisms |
| Less connections between neurons | Nature of the connections between neurons | Learning leads to increasing connections between neurons |
| Less varied, occurs over shorter distances, occurs more immediately | Means of communication | Varied across the senses, Occurs over long distances Occurs over a considerable span of time |
| Little or no memory storage | Memory storage | Longer memory storage |
| Less variety | Resource Variety | Choose from a myriad of sources such as insects. Expand to new niche |
| As a reaction to low temperature, genetic variants can appear such as fur or blubber | Strategies reaction to low temperature | As a reaction to low temperature Make clothing, use clothing |
| social insects and other invertebrates wasps can walk, fly, eat, find a mate, prey w/o learning | Examples in nature | Chimps, crows, ravens, dolphins Hominids |
| Slow ecological change | Driving force | Rapid Ecological change |
| Simple organisms | Organizational complexity | Multicellular organisms |
| Stay in familiar ecology, have to compete | Strategy | Forced to explore new ecologies |
| Non-motility | Stable or movement? | Motility |
| Become dormant | Responses | Initiate moving to new niches |
| Be transported by animals, wind and water | ||
| Plant life | Forms of life | Animal life |
| Photosynthesis | Sources for reproduction | Trapping animals using cunning |
| Seed dispersal | Meat-eating for concentrated protein and brain development | |
| Concentrated, evenly distributed | Resources | Patchy, unevenly distributed |
| Sending and receiving signals: emission of a signal and immediate response to it | What happens with signals? | Learning and teaching. Emission of a signal specifically designed to alter the behavior of another |
| Reaction: Instinct: entire behavioral act is directly inherited act performed without instruction or trial and error |
Type of conduct | Response Comes from society or culture. Trial and error |
| Insects –fixed response: fixed action pattern in orientation to light | Learn correct response rather than fixed |
Early Beginnings of Culture
In the grand sweep of organic evolution the nature of adaptation splits in two directions: one branch remains in a given niche and continues to compete within that niche. The other explores new niches. It no longer competes or competes with those that remain in the existing niche. In the case of the relationship between land and sea, plants and animals came to a branch point. Some remain aquatic while others mastered various innovations that would be required to survive on the terrestrial environment.
The first change required in the exploration of new environments is the increase of motility and the second is the evolution of the brain. As a result of the centralized brain follow
- the integration into social groups
- the ability to learn
- the ability to teach
- the increasing flexibility in behavioral response—multiple choices as opposed to one or two choices.
Many birds and mammals have a kind of primitive culture in which behavior is transmitted but more to imitation rather than by teaching. True culture must not only have behavioral transmission but also must provide a respond to that information which includes multiple possibilities.
Five Kinds of Behavior That Lead to Non-Human Culture
- physical dexterity—tool use
For example, the holding of thorns in the beaks of Galapagos finches to remove grubs from trees and the use of rocks to break abalone and other mollusk shells by sea otters and termite foraging among chimps. This includes such considerations as where to poke, what kind of stick is best and how to twiddle the stick. The manner in which the young are fed by oystercatchers also involves tool use. Bonner points out:
“They either put the mussel on some hard sand and peck or hammer very hard with their bill to break the shell at its weakest spot or they insert their bill into the open siphon (when the mussel is under water) and snip the adductor muscle which keeps the valves of the mussel closed”. (173-174)
- learn rather than inherit information about predators
With the increasing motility across land, it is to the prey’s advantage to be able to identify new predators and adapt to different predators in different ecological contexts.
- auditory communication within a species
Any learned bird song can play a role in individual recognition. Also, dialects support group cohesiveness. In the case of New Zealand saddleback they do not learn a song solely when they are young but can learn songs at any time in their development. Among the chingolo sparrows, the males are known to wander and when they arrive at a new destination they can learn a new dialect different from their own.
- geographical locations are partly cultural
While the general direction of birds, north in the spring and south in the fall, are built into the brain and influenced by hormones, the exact path or location of final destination is cultural. In his work with geese, Lorenz was able to introduce new places to geese because he was imprinted upon their brains as a “human foster mother”
- inventions or innovations
In the four areas above there is learning and imitation. Innovation is the first time any of these new behaviors occurred. In terms of physical dexterity. For example, the first time any new tool is used or the first-time titmice birds in Britain opened milk bottles by pecking through the aluminum foil. Also, is the first time macaques washed the sand off sweet potatoes before eating them.
Human Culture
The development of the brain not only improves the ability to form sustaining relationships with members of one’s own species as a social means of adaptation. With increasing brain size there is the increased ability to recognize individuals of one’s own species. Pair bonds can form, be extended to kin and eventually expand to non-kin. The number of recognition signs and signals also increases. The brain not only allows the ability to make multiple choices and to learn and be social, but through the increase in the art of true teaching humans develop a more expansive and precise culture by an increasing art of true teaching. By this Bonner means not simply imitation but a new action which is the result of a specific instruction by the teacher. This is only possible with a specific verbal language.
In part, culture is a product of a crisis in the development of the size of the brain. If the brain were to become too big, the birthing process would become problematic. To resolve this, nature selected a few genes that affected the timing of development so that the growth of the brain could be completed outside the parental body in interaction with the socio-cultural world.
