To Kieran Tapsell, a man who seemingly violated the sacred injunctions to selfishness that address us since early zoological times, taking on the translation of this hefty book merely for the pleasure of making it accessible to friends.

The author

This book is a journey around the human being, Homo Sapiens, with the intention of examining some of his behavior and explaining it from the evolutionary point of view. it tries to use a magnifying glass to look at the so called universals of human conduct, knowledge of which today begins to constitute the new and powerful discipline known under the name of evolutionary psychology. The final product is a synthesis of ideas and of results already established, coming from fields as diverse as genetics, evolution, anthropology, neurology, epistemology, cognitive sciences, ethology and of course, psychology.

By universals, we mean behavior observed in all the cultural studies done by anthropologists and which appear not to depend on the particular things taught in each human group. The interesting thing about the synthesis which we get is that it turns out that an important part of the complex collection of human behavior can be explained by a unifying principle: the direct or indirect search of the greatest number of sexual partners of the best possible biological quality; that is to say, the search for the greatest reproductive efficacy.

The miraculous magnifying glass is the Darwinian theory of evolution which gives us a refreshing look at one of the oldest problems of man, that is, the reasons for behavior, the reasons for wrong behavior, for the surprises, stupidities, and contradictions, for those things running against the current of logic and common sense. And the explanation which comes out is coherent with nearly everything that can be observed in human societies. And so, much of the knowledge which psychology contributes is explained as a result of an evolutionary process, using as its premise that the majority of modern manīs desires, his impulses, interests, inclinations and mental faculties have been designed by the evolutionary process of the species with the purpose of maximizing reproductive efficiency.

The American psycholinguist, Steven Pinker (1977) says that man behaves as if someone is whispering inside of him what is the most convenient for his coefficient of reproductive efficacy. He says that that without knowing the rules of the genetic relationship, nor the physiology of human reproduction, man has learnt to behave as if he knew them, constructing systems which are invested with the same direction of the evolutionary interest.

What happens with foods is similar: they learn naturally to choose nutritious things and to reject what does not contribute calories. And they don't allow themselves to be deceived.

This book says that modern man is the last link in a long and continuous evolutionary chain, in which the earlier links are animals which were becoming less and less rational as we sink back into the past. And the continuity of the chain demands that there is a certain continuity in the behavior. The Austrian doctor and ethologist, Konrad Lorenz (1993) confirmed that the structure of feeling, thinking and acting of humans contains innumerable historical leftovers from the epoch of his animal ancestors, leftovers which reveal themselves unpredictably. For that reason, the attempt to understand man, without having any knowledge of the species which have preceded him is the equivalent of trying to build a house starting with the roof. The way which leads to the understanding of man, passes through the understanding of animals, in the same manner that the way which led to his appearance, passes, without any doubt through this. The Colombian essayist, Andrés Holguín (1998) says, with a great economy of words, “The origin of man is not tied to the divine, but to zoology.”

If one wants to understand man, such aSexual ssumptions require man to examine animal behavior. From there, we look at and analyze first the behavior of animals, preferring, as it is elemental logic, the higher species which are closer to us from the genetic point of view. Afterwards we study the biological or reproductive (adaptive) advantages, taking into account natural and primitive conditions of the environment which possibly surrounded men of the past and finally we look for the mentioned behavior and its traces in man himself.

Given that it was only in recent times that we knew the details of the reproductive process, it is logical that man of yesterday and the ancestors of man and with even greater reason, our non rational ancestors, could not understand how the devil they produced their offspring, notwithstanding that they knew from where they came, and that it had nothing to do with the storks, and so it turned to be normal that their natural impulses pointed them that way, on the one hand in the direction of having the greatest number of partners, or what is the equivalent, of mating (their heirs would increase by addition and on the other hand, to defend the offspring that they had, which will give them more carriers of the family genes. As a consequence, the term, adaptive is used principally to indicate what is trying to be achieved by these two purposes.

When we talk about adaptive advantages in this book, then this should be understood as those advantages which return the greatest amount of mating, directly or indirectly and in the care and successful reproduction of descendants. The questions should be formulated in the past, because in actual life, with high technology and great scientific development, the old natural law that the number of heirs is directly proportional to the quantity of mating, no longer applies. Besides many citizens do not want so many children any more and they don't have the time to bring them up and educate them. One should not lose sight of the fact that modern man is a domesticated animal, incapable of surviving if he had to return to the natural niche of his remote ancestors. Today he occupies the niche offered by the great human collectives, very far removed from where the greater part of evolution occurred. Besides, one is talking about a dehumanized niche, which the great collectives are, the callous corporations and insensitive powerful countries.

In summary, every form of behavior which is found in modern man — the completely universal human — has adaptive functions and they are found amongst the higher species of animals, and it is very probable that they have genetic foundations. Let us not forget that genes are manifested in behavior by indirect means. Hardly anyone makes love thinking of making copies of their genome, but rather does it to have fun and to satisfy their sexual impulses, and they do not look after their children because they think about them passing on their genome; they look after them, - says a biologist, very keenly, because they cannot avoid it. The genes achieve their “objectives', directing the formation of neuronal nets which make sex attractive and so that an individual feels love and interest for young ones, the natural fruits of sex itself.

An important and very modern subject is the spermatic struggle: semen behaves like a great organism which fights so that its owner is the one who fertilizes the woman. Apart from the fact that reproduction in the actual world is controlled by pills and other anti-contraceptive methods, we continue to be manipulated by the same imperatives, looking for sex with the same intensity, independently of the fact that it is translated into more copies of our genome.

Within the so called synthesis one studies and puts forward the thesis that we humans come into the world endowed with an appreciable number of criterions to judge the smell, the taste, the esthetic, the ethical, the humorous, and the dangerous, as well as to a mixture of psychological characteristics which can be interpreted as archaic residues of a past which has already been overcome. To these innate things, there has been added, later, cultural experiences, which modify them without making them disappear completely. it describes and explains the different stages of sexual evolution up to the point of arriving at the complicated human sexuality. it studies the generic roles and it tries to justify its appearing and consolidation through means of adaptive arguments. Likewise, it defends the thesis which proposes the existence of an important biological component in homosexual behavior.

In the book we agree with and support the theory of Noam Chomsky over innate linguistics and how it relates to the cerebral architecture, the recent discoveries arising from cerebral accidents and the most recent investigations over the pre-linguistic behavior of the newly born. From the field of psychology we take the theory of Jean Piaget over the development of intelligence and we present that as the inevitable consequence of a predetermined genetic structure, an interaction with an exterior means. We study the playful behavior of a child and point to the importance of early stimulation for the completion of the neurological circuits, from which arise, in a natural way, the explanation for some astounding achievements, both physical and intellectual of some gifted people who early in life learnt exactly those activities for which they have facilities. We take a run through the apparatus of human cognition, forged by evolution in the many centuries of adaptive change with the purpose of answer in an appropriate manner the challenges of the niche of the social human. We study the problem of inter subjectivity and we try to explain the creativity and appearance of geniuses. Likewise, we will make a brief run through the difficult enigma of consciousness. One whole section is dedicated to studying cerebral pathologies and their strange results.

One important subject is represented by the stages of social evolution. We will show how, in this slow evolution of life through groups, there have appeared some sins, like xenophobia, envy, greed, usury, the exploitation of the weak, vengeance, resentment, terrorism, hypocrisy, manichaeism and certain unique aspects of the human species like feelings of blame, or remorse, and the sense of humor. Selfishness and altruism deserve a separate chapter. As a novelty and using an evolutionary focus, we will look at an original way of looking at economic theory, based on human nature, and not simply reason, which has given rise to a new discipline known as the economics of behavior.

In addition to that, we will study some specific limitations of the human intellect, called biases, as well as other disgraceful and stupid characteristics proper to humans. Aggression, and all the things that go with it, like the impulse towards making hierarchies and territoriality are presented as responses of an innate origin and highly adapted in the pre-cultural past, tending to resolve a complex combination of situations created by life in community. From this picture of behavior come explanations for blind faith, the facility to allow ourselves to be indoctrinated which almost all human beings show, the conservative spirit of the old and the rebellion of adolescents, the excessive aggression of sportsmen, the violence against “heretics”, terrorism without boundaries, administrative corruption etc….

Almost all of the themes relating to human conduct are thorny and controversial, but none so much as the difference between the sexes. The central problem sits in the lack of equality in the designs of nature, an imbalance which, in the higher vertebrates, especially, punishes the feminine sex with its preference; however, a study of man which claims to be complete, cannot ignore such important subjects, and besides, the euphemisms and hypocrisy when dealing with the subject will only create misunderstanding. in consideration of this, the author expects and offers apologies for certain statements which, to women's ears might sound unpalatable.

It is not too soon to warn the reader that this book was constructed over the ruins of a first book entitled: Man: Heritage and Behavior. As well, the old book was completely demolished and reconstructed in the light of the infinity of new knowledge which has been coming in over the last two decades and which has occurred since its publication. For that reason the unsuspecting reader who knows the original book could find some subjects which sound familiar but you can be sure that this is a fresh, modern, more ambitious and more complete book, better argued, with greater content.

The bibliographical origins of the quotations are written in brackets with the date of the edition of the work, as they appear in the bibliography. When it is necessary, the surname of the corresponding author will also be written within the same brackets. The reader will excuse the presentation of a few quotations without bibliographical reference. The reason is that, through the disorderliness of the author, every trace of it has been lost. To help those readers who are not accustomed to biological terms, i have put in, at the end, a glossary with the scientific terms used most frequently in the book.

I want to acknowledge my appreciation of the friends and relatives who had the patience to read the originals and who helped me with their wise observations in the endless task of improving the material and reducing errors. Finally i want to thank Villegas Editores for the work of correction and editing of the present work.