Chapter 1.c
HUMAN NATURE
Let’s have a look inside ourselves; let’s commit to apply the acquired knowledge for understanding the nature of human beings.
It is a theme to which it is normally given a value of insuperable complexity, if not mysticism, which discourages or even frightens any solution. To reassure the hearts and simplify the work, we need to learn knowledge related to evolutionary strategies, with particular reference to the winning ones peculiar to man
1.c.1 – What are the evolutionary strategies?
What are the evolutionary strategies?
The living beings adapt to the environment in which they live to meet their needs of survival. These exigencies can be seen as problems to solve, problems whose solution lies in a reply of adaptation, i.e. in development of appropriate strategies through the biological evolution.
Among the fundamental evolutionary strategies, we must remember the following: symbiosis, group, specialization and sexuality.
OTHER EXAMPLES
MIMICRY
1.c.2 – Is symbiosis an important evolutionary strategy?
Is symbiosis an important evolutionary strategy?
When the individuals of two different species live together to obtain a mutual benefit, it is realized a phenomenon of fundamental importance defined symbiosis. This relation is sometimes so close that the two units end with forming a single body; is the case of lichens, which are bodies formed from the merger of a mushroom with a colony of unicellular algae; the fungus provides nourishment for algae, water and minerals, and support for better lighting and ventilation, while the algae in turn feed the fungus with the organic molecules produced through photosynthesis.
An example of symbiosis in the animal world is given by the Egyptian trochilus and the Nile crocodile: the trochilus is a bird that feeds cleaning the teeth of the crocodile from annoying residues of food, getting in return protection and food.
The examples of symbiosis are very numerous and some of them have obtained a great success; we can recall the symbiotic relationship between plants and fungi living in their roots that allows plants to absorb phosphorus and nitrogen, indispensable to their metabolism, while plants allow mushrooms to eat their own sap.
Symbiosis is one of the oldest evolutionary strategies. We have seen how one of the fundamental steps in evolution of living beings is given by the appearance of protists, i.e. bodies that are distinct from bacteria by a much more complex internal structure. This structure is formed by a nucleus that joins with other parties, isolated from internal membranes and thus distinct, which, by carrying out specific functions, represent the real internal organs. Some of these organs, the mitochondria, have within them their own DNA molecule, and then a genetic heritage that reveals their true nature: they are the descendants of ancient bacteria able to use the waste products of other chemical cellular reactions to feed themselves and derive the energy necessary for life; the above is carried out with a much higher efficiency than that of the cell their host. Over time, these bacteria have become the power plant of the cell, obtaining in change a constant and secure source of nourishment.
A similar situation is in the case of chloroplasts present in the cells of all plants: they are the evolution of ancient bacteria able to carry out photosynthesis.
It is crucial to know that the mitochondria are also present in the cells of all animals and also in humans.
This is a symbiotic strategy that led to evolutionary success of protists.
The idea of creating new life forms through the merger of different species Is called symbiogenesis, and it is now clear that it has played an important role in evolution, since it allowed to combine the capabilities developed and improved by different species of bacteria (such as the use of sunlight and oxygen as a source of energy) with those of autonomous movement peculiar to complex cells. This way, chances of survival otherwise unthinkable were seized.
The symbiosis may seem a survival strategy far away from the life of human beings, but reality is quite different. For example, in human intestines, as in that of many other animals, there are colonies of bacteria that help us in digestion and in the defense from infections, having in change a safe and easy nourishment. The number of such bacteria gives us an idea of the vastness of the phenomenon: we know more than 400 different species of them.
We must also remember that every cell of the human body, like those of all animals, contains a large number of mitochondria and is thus in turn a symbiotic body . The symbiosis is therefore essential to our lives.
FURTHER INFO
CHLOROPLAST, LICHEN, MITOCHONDRION, SYMBIOSIS
ROYAL BOX
LYNN MARGULIS
1.c.3 – What is the use of living in a group?
What is the use of living in a group?
An old and well-known proverb tells us that unity is strength. This principle is been exploited not only with the symbiosis of different kinds, but also through alliances and cohabitation between members of the same species. These, rather than living isolated, can meet in groups with multiple advantages: in a group, predators can encircle the prey, the prey in the flock can better defend themselves from predators; together can carry out activities otherwise impossible, for example, the ants may build huge anthills only through cooperation.
The strategy group is very old and, as in the case of symbiosis, may be so extreme as leading to formation of a single body; it is apparently successful in the first multicellular beings, descendants from colonies of unicellular organisms, so closely associated with their group that they cannot live without it.
ROYAL BOX
FERDINAND TÖNNIES
1.c.4 – What’s the use of specialization?
What’s the use of specialization?
The species coexisting in a given environment can all be seen as a great and numerous community that tries to exploit all possible resources in order to perpetuate life.
Considering that the same structure cannot be suitable for all applications, in order of making the best use of various resources (that could be the different sources of nourishment), it was necessary to generate a growing variety of species, each specialized in conducting a particular lifestyle that takes advantage of special resources or favorable conditions. In this communities of species, called ecosystem, every form of life carries out a particular role as an actor in a drama. Surviving therefore means to obtain one of the available roles; this place is often defined as ecological niche.
A similar phenomenon occurs in the community formed by a single species, because, in order to make the best use of every chance of survival for the group, this forms inside of itself a populations specialized in performing a given activity. If we take as example an anthill, we can see that there are worker ants, warrior ants and a king and a queen for breeding purposes.
The same process was developed with the first multicellular beings, whose cells have specialized forming different tissues. The great anatomical complexity of the other animals is then due to the phenomenon of specialization.
FURTHER INFO
ECOSYSTEM, ECOLOGICAL NICHE
ROYAL BOX
LOUIS PASTEUR 
1.c.5 – Sexuality leads to genetic mixing?
Sexuality leads to genetic mixing?
Sexuality is a strategy that allows to reuse the genes already available through a different association. The result is similar to that of a mutation but, unlike this, regularly occurs in every reproduction act. The advantage may be insignificant for the individual, but is crucial for the species and its future evolution: by mating occurs fertilization of the egg in which the mother genes recombine with those of the father; thus the descendants of an individual will be able to exploit the positive mutations arising in the other parent, bringing the benefits of evolution arising from different sources; with this procedure we obtain something similar to what symbiosis achieved by combining the different capabilities of different species. The new combinations can also be negative and, in order to diffuse only the positive ones, the intervention of natural selection is necessary. Similar considerations were made even talking about the phenomenon of mutations but, unlike this, which is slow because based on rare events, the phenomenon of sexual reproduction creates new combinations at each new birth and then generates a much higher number of variants. The result of this phenomenon is a much greater capacity and speed of adaptation and this is the great advantage of evolutionary sexuality: it is no coincidence that virtually all animals and plants that we see around us use this technique.
The phenomenon of sexuality joins that of specialization and the result is that in reproduction both parents play different roles; since for playing different roles, different characteristics are necessary, the evolution has led to the creation of two types of sex: male and female.
It seems that the protists have been the first beings, with unicellular nucleus and internal organs, to develop sexuality and, since then, the strategy was no more abandoned. From a greater capacity and speed of adaptation has resulted a faster evolution and diversification.
The appearance of the first unicellular beings with sexual reproduction occurred around one billion and a half years ago and this corresponds, as we have seen, to h. 16:00 on our evolutionary day. Before then, only the bacteria had developed, who reproduce themselves by scission, i.e. asexually; evolution, for almost three quarters of history of the Earth, has produced thus only the bacteria, while with the advent of the first protists, in the last quarter or so, all the forms that we know, and those extinct too, have developed. This incredible acceleration is due to the development of sexuality. It is therefore reasonable to assume that evolution has a natural tendency, irregular and tied to random events, both in terms of adaptability that results in the production of individual variations, and in terms of speed of adaptation i.e. the production of new species.
FURTHER INFO
FERTILISATION, REPRODUCTION
ROYAL BOX
WALTER SUTTON
1.c.6 – The egg is an organic shuttle?
The egg is an organic shuttle?
Sometimes it happens that living organisms are in the need to colonize an environment quite different from the original, so different to be prohibitive for survival. Often there are no alternatives to death but some species have been successful in the enterprise, thanks to a simple but ingenious strategy: to create a protection around them, a sort of housing within which preserving or reproducing a portion of the original environment.
This is what vertebrates did passing from the oceans to the mainland; Indeed, their skin became a waterproof casing that prevented a rapid dehydration and that kept inside an environment favorable to life of their cells. Even today the salt concentrations in the blood and other body fluids of mammals, as the sweat and tears, are very similar to the ocean, that is that environment that was our first cradle, which we have abandoned about 400 million years ago, but that we still carry inside us.
The same strategy was used to allow the development of their offspring: eggs of reptiles and birds, and the uterus of mammals, reproduce the wateriness, the hydrostatic drive and salinity of the original water.
This technique is perhaps the oldest of all: it is in fact assumed that inside the cell membrane of bacteria, as inside the nucleus of some more complex cells, an environment similar to that in which life was born is reproduced.
It is a simple, essential and ancient technique but always valid; it is actually the same as we men use when we build submarines and space ships, which are large containers of a portion of Earth environment, with air for breathing and controlled temperature, which can travel in environments for us uninhabitable.
ROYAL BOX
ANTONI VAN LEEUWENHOEK
1.c.7 – Perception and response: an important sequence?
Perception and response: an important sequence?
Even living in the same environment, we can find in very different situations: shifting from day to night and vice versa; from warm to cold, from drought to rain; from insulation to the company, and predators can become preys. The life depends on these environmental changes and all the bodies, in some way, react to these stimuli. For reaction is therefore meant the creation of a change and this change may be physiological, as the reaction of the immune system in the presence of an infection, or behavioral, as a quick flight in presence of a predator. When a stimulus of the outside world leads to a consequent reaction, one can say that the stimulus was perceived; i.e. a signal that triggered a response was somehow received.
Considering the obvious and vital importance of this process, it is immediately understood how, during evolution, a myriad of systems for perceiving any sort of stimuli and to respond to them with a speedy reaction, has developed.
The unicellular beings are already able to respond to a wide variety of chemical and physical stimuli: for example, when they are in contact with nutrients, they produce the enzymes necessary for their absorption.
Even the plants are sensitive to different types of chemical and physical stimuli; their activities, for example, change from day, during which produce the substances they need through photosynthesis, to night, during which such activity stops. Plants are moreover able to do much more: it was found that in the presence of an invasion by pests, some plants not only have a chemical reaction of defense, but also emit in the air substances that, perceived by the other plants, activate their defenses enabling them to anticipate the attack. It is therefore a genuine chemical communication consisting of stimuli and appropriate reactions.
In the animal world, where for surviving it is necessary to identify a prey or a predator, the greater need to perceive and react led to the formation of the sense organs and nervous system. Thanks to the bodies specialized in the perception of certain stimuli, the animals manage to locate their prey or their predators, feel the presence of their own kind and many other things. Very early in their history, animals have developed a system to manage the amount of information from their senses and to give a comprehensive interpretation: this is the nervous system, which is formed by neurons, very specialized cells capable of transmitting electrochemical signals at high speed to one another.
The neurons form in the body real communication channels, through which the stimuli perceived by the senses are transmitted to the brain, that is a sort of centre of coordination determining the most appropriate reaction. This latter, in some cases, may necessarily result in a given motion.
The brain then manages the sensations and accordingly guides the movements of the body, but also performs many other functions; among them, two have a fundamental importance: memory and learning.
FURTHER INFO
SENSORY SYSTEM, NEURON, NERVOUS SYSTEM
ROYAL BOX
IVAN PAVLOV
1.c.8 – Are memory and learning evolving strategies?
Are memory and learning evolving strategies?
Thanks to memory the brain is able to recognize feelings already felt and accumulate experience; when facing a new problem, every animal can react with generic, uncoordinated and random actions but certainly will remember the one that has proved to be more effective; in a subsequent and similar situation, to remind it will save time and efforts. We are facing a new form of adaptation; after genetic adaptation, which requires a large number of generations, we are now considering the intellectual adaptation, which, even if limited to a single individual and consequent to a period of apprenticeship, offers major advantages: thanks to memory and learning, animals can develop a great number of specific reactions, enabling him to swim, run, climb, fly, hunt, build lairs and many other things to be done at an appropriate time.
These faculty of the brain, already present in marine flat worms, which are rather an archaic group, probably have developed to learn to move on the uneven seabed, but we know that they are the basis for important future developments. These abilities, which can be summed up in the term “intelligence”, were maintained in all main groups that have later evolved, and this demonstrates their importance and versatility.
These strategies, perhaps with minor modifications, have allowed the colonization of a wide variety of environments. This brilliant result is called evolutionary success.
Now let’s consider the strategies that led especially our species to the evolutionary success.
FURTHER INFO
LEARNING, INTELLIGENCE, MEMORY
ROYAL BOX
HERMANN EBBINGHAUS
1.c.9 – Is handling essential for man?
Is handling essential for man?
Hands and arms are much more ancient structures than we are, so much that they were already present in amphibians in an almost identical form. They are a perfect example of pre-adaptation to various functions: if in the first amphibians they were a simple point of support, in subsequent forms living on trees, the movement and mobility of the thumb have made them capable of grasping the branches so that they can climb. All mammals living on trees are able to use their hands in this way, but some of them have found other uses: the squirrels use them to bring food to their mouths, monkeys use them even for cleaning the body and to care for the offspring and finally the great apes use them to build shelters and small tools. This was possible thanks to a increasing mobility and coordination of the fingers and especially the thumb, which has evolved becoming able to precisely oppose to the tip of the forefinger.
The ability to manipulate objects has been developed further in humans, whose hands have a more square and less elongated shape compared to monkeys next to him, so that the thumb of man can reach easily and with great speed the tip of each finger; this shows how the main purpose of hands is no more to cling to branches. The number and sophistication of the instruments constructed and used by human hands has become incalculable, so that its most apparent feature is perhaps that of being a manipulator of objects. The importance of this faculty in our lives is obvious.
ROYAL BOX
GIOVAN BATTISTA MORGAGNI
1.c.10 – Socialization is found in all human major activities?
Socialization is found in all human major activities?
The socialization is a variant of the group strategy which allows members of the community to maintain its own movement autonomy. This is a strategy very common among mammals and almost universally used by monkeys; it is therefore linked to the evolutionary success of many mammals and in particular of man, who has not only inherited, but has also further developed it.
Without any particular training, a man left alone in a in a forest or grassland has less chance of survival than a monkey isolated in its environment. This demonstrates a greater degree of dependence to group, i.e. the need for an articulated socialization.
The human community, especially the most recent, have a high level of specialization with a high number of sub-groups that are dedicated to particular activities (workers, doctors, teachers etc.). This is also typical of the groups in which the link between the members is very close.
Man, a set of specialized and interacting organs, in turn consisting of symbiotic cells, has thus the need to exploit even the phenomena of the group and the specialization in their social organizations.
It is worth noting here that all the main activities of such work, protection, the search for food, etc.., occur through some form of collaboration and then through a social contact. The ancient herd of monkeys has thus evolved enlarging itself, specializing and becoming complex up to levels never seen before among mammals and, perhaps, throughout the animal kingdom. Such a development, which historically goes hand in hand with the expansion of the human population, is surely one of the bases of its evolutionary success.
FURTHER INFO
SOCIALIZATION
ROYAL BOX
MAX WEBER
1.c.11 – Is word the first stone of human culture?
Is word the first stone of human culture?
To coordinate the activities in a society as complex as human is, an efficient communication system is needed.
Today we know that our movements are coordinated by a complex system of internal communication that is the nervous system, which cells use a complex electrochemical language. Similarly human beings use a complex language made of gestures, facial expressions and, above all, of words. Even in this case, it is an evolution of language used by monkeys, which use both visual signals and sounds; as previously seen for the group, also the complexity of language is considerably increased, particularly for what concerns sound signals.
We humans have in practice a different sound to indicate any type of object and action that we are able to conceive: i.e. words. We can achieve such a miracle, through appropriate modifications of the voice refined by evolution, of being able to modulate and articulate an enormous number of sounds at high speed. The words are associated with each other to express more complex concepts and this according to conventional, very intricate rules, called grammar and syntax.
A similar evolutionary and intellectual effort leads to an exceptional ability in communication, allows to sharpen faculties uncommon in the animal world, including monkeys; this is a faculty that goes beyond the need to manage public relations: it must therefore have been developed for another purpose.
The word enables communication of complex concepts and this, if it can be unnecessary for the purpose of socialization, is indispensable in specialized work that, as we have seen, is an essential and successful peculiarity of the human being.
The purpose we mentioned before is then the formation and transmission of culture, i.e. the body of knowledge tending to increase and to become increasingly complex.
FURTHER INFO
LANGUAGE
ROYAL BOX
NOAM CHOMSKY
1.c.12 – Is culture an integration to the genetic heritage?
Is culture an integration to the genetic heritage?
In nature can be observed three types of behaviors:
– innate behaviors, such as the crying of babies or their attachment to maternal breast;
– discovered behaviors, or everything that we learn from direct experience, as the ability to maintain the balance;
– cultural attitudes that are learned by others, both by imitation and through teaching.
A behavior discovered from direct experience can be culturally transmitted to the others. Culture, therefore based on experience of the others, allows to overcome the limitations of personal experience.
The transmission by culture of knowledge useful to survival is a strategy often used by mammals, which spend much time to care for the offspring and teach them what is necessary.
At this point, it is important to note how in cultural heritage there are many affinities with genetic heritage:
- survival depends on it
- it is heritable
- undergoes mutations
- is subject to natural selection
- contributes to environmental adaptation through appropriate behavior
- evolves over time.
The cultural heritage, considering its contribution to survival, can be then reasonably regarded as an integration of the genetic heritage.
It should be remembered, however, that among these heritages there are also some significant differences:
- Culture is not innate: it needs a period of learning; in case of premature death of parents may also be lost, but the social animals may also learn from other members of the flock, thereby balancing the loss of parents
- a new discovery can be transmitted to the whole community and not only to their offspring
- an individual can’t change its genetic heritage, but it can change the cultural heritage and may do so several times, resulting in a form of individual development.
These cultural characteristics can give to cultural evolution a speed of adaptation unthinkable for genetic evolution: mutation can spread to the entire flock within a single generation.
Man, thanks to the word and to the brain which can use it, is capable of transmitting experiences and knowledge in a very detailed and effective way. The great number of inhabitants in human communities also allows a man to manage a huge cultural heritage, and this still thanks to the phenomenon of specialization, which in human societies is not in the physical form, but cultural: a warrior ant is physically different from a worker and distinguishes itself easily to naked eye, while there is no way to distinguish a lawyer by a doctor until we don’t see them at work.
We have already established that the successful evolution of man is based on its ability in using every kind of tool that he builds himself, thanks to technology, and on a very large and specialized society; however, these pillars are based on turn on the platform of culture, which is then the basis of primary evolutionary success.
ROYAL BOX
EDWARD BURNETT TYLOR
ABSTRACTS
n. 5 – CULTURAL HERITAGE 
