Chapter one from the book One for All - facts and values ​​in the debate about the evolution of altruism

How were social groups based on cooperation created and maintained throughout evolution? This is one of the major issues that have occupied evolution researchers since the days of Darwin. In the last four decades, there has been a lively and resonant debate between alternative explanations - at the level of the kindergarten, the individual or the group - for the evolution of altruism

By Ayelet Shavit

From the cover of the book

How were social groups based on cooperation created and maintained throughout evolution? This is one of the big issues that have occupied evolution researchers since the days of Darwin. In the last four decades, there has been a lively and resonant debate between alternative explanations - at the level of the kindergarten, the individual or the group - for the evolution of altruism. The author articulates the nature of the common problems and failures in the debate, tries to establish the sources of these failures and offer lines of thought that will allow them to be avoided in the future.

According to the author, the bias in favor of searching for the cause of universal altruism and in favor of a narrow sense of 'group', downplays the importance of experiments and observations on the local population. The result is an inconclusive semantic debate that completely rules out group-level deliberation or finds this process anywhere. Unlike other books written in the field, according to the author, the roots of this strange behavior lie, among other things, in the value-political charge that accompanies the concepts, the author reveals the hidden and branching dialogue between science and values, and argues for the pluralism of selection processes in the evolution of altruism.

The book is an original and multidisciplinary contribution to the study of the evolution of cooperatives. It enables a renewed discussion from a fresh and critical point of view on classical problems in evolutionary biology and the philosophy of biology, and raises fascinating questions related to the history and sociology of biology and the complex relationship between science and values.
From the introduction by Prof. Yamima Ben Menachem and Prof. Chava Yablonka

Eilat Shavit's book discusses the various explanations for the question of the evolution of altruism, and the nature of the process of deciding between these explanations among evolution researchers. The author articulates the nature of the common problems and failures among researchers in this field, tries to establish the roots of the reasons for these failures and, following these insights, to offer lines of thought that will allow them to be avoided in the future.

On the same subject: How can altruism be explained?

Chapter One: The Debate on the Evolution of Altruism

Since the days of Darwin (1882-1809), but especially in the last fifty years, there has been a lively debate on the evolution of altruism and cooperation through group selection. Despite the continuation of the debate, the debate is still heated and arouses great interest among researchers.

The purpose of the book is to analyze the scientific debate by clarifying the concepts used by the debaters, the practice they employ and the values ​​that guide them. It will become clear that great scientists are also, first of all, people: with a world of images, values, feelings and memories, which are not separated from their scientific work.

In this chapter I will introduce the main characters participating in the debate; the accepted explanations for the evolution of altruism: selection at the level of the kindergarten, at the level of the individual or at the level of the group; And some of the professional concepts that were already in the public domain: selfish gene, evolutionary equilibrium (ESS - Evolutionary Stable State), game theory, prisoner's dilemma, mutual altruism (reciprocity), the principle of respect (handicap) and group selection (group selection). In the second chapter I will focus on the analysis of the concept of 'group selection' and the criteria for experiments examining the selection processes in the evolution of altruism.

I will therefore first present the principles of natural selection and the evolutionary response to selection. It will clarify the difficulty in explaining the evolution of altruism through selection at the level of the organism, and clarify why the research turned to selection at the level of the garden. Sometimes it seems that the Ramat HaGan clarification model has now become, in the eyes of the general public, the main model - if not the only one - for explaining the behavior of animals and humans. In this chapter I will present the advantages of explaining the evolution of cooperation through genetic selection, but I will also emphasize the practical and theoretical difficulties in progressing this type of research. This will clarify the researchers' renewed interest in individual selection and group selection and a variety of other explanations will be presented regarding the selection process at the individual level and at the group level.

Some of the differences between genetic selection, individual selection and group selection are semantic differences, which concern the meaning of the concepts and not the facts. Meaning, there are debates about altruism that cannot be decided through experiments or new observations. These discussions will be briefly reviewed here, but those aspects that can indeed be decided through observation will be emphasized. In general, in my book I will present the advantages of the empirical point of view, the one that focuses on experiments and observations, and I will try to explain how this empirical debate has been going on for so long without progress, without a decision, but also without decay. I will therefore start with the basic terms.

natural selection

Natural selection is the result of certain starting conditions: a population consisting of individuals with variance regarding the relevant trait, and an environment with limited resources, in which there are individuals who are able to utilize these resources better than others. These individuals are expected to produce more offspring that will reach sexual maturity, and are In order for the trait to become evident through natural selection, a sufficient frequency of individuals carrying it is also required, so that random drift within the population—for example, the death of individual individuals from a random lightning strike—could not be the reason for the extinction of this successful but rare trait from the world.
However, in order for the process of natural selection to also lead to evolutionary change, it is not enough to change the frequency of the trait that was selected during that generation, but the change must also exist in future generations, and for that it is essential that the variation, that is, the difference, regarding that trait be inherited. Only heritability of the variants guarantees a change of the mean of the trait in the population in the next generation, meaning an evolutionary response to selection.

In the history of the debate about the group, the individual or the gene as the unit of selection, the debate is mostly focused on explaining the evolution of traits of a certain type: altruistic or cooperative traits.

Biological altruism and psychological altruism

Altruism is a concept that carries a different meaning for the biologist than it carries for the speaker in everyday language. The interest of evolutionary research is solely in the effect of the trait on increasing or decreasing fitness. 'Fitness' is the expectation regarding the number of offspring that will reach sexual maturity. Biologists define a trait as altruistic when the individual carrying it reduces his relative fitness and increases the relative fitness of his group members. In fact , even if the individual's behavior is expected to result in an increase in the number of his descendants but a greater increase in the number of his friends' descendants, the act will be defined as altruistic, because relatively speaking his friends are expected to benefit more than him. Even a minimal reduction in the relative fitness of the individual will be considered altruistic behavior.

In this sense there is no distinction between 'altruism' and 'cooperation', and in the book I will use these two terms interchangeably as equivalent, as is customary in the literature. For the biologist, the term 'altruism' does not specifically indicate extraordinary acts of sacrifice, but rather focuses on routine social activity, such as an individual going out hunting with members of his group instead of resting in the shade, or allowing additional individuals to eat from the prey instead of trying to eat it all alone.

In contrast to the language of evolution research, in everyday language and psychological discourse we are mainly interested in the intentions and motives of the agent, that is - behavior that increases the competence of another but is motivated by self-interest will not usually be considered an altruistic action. For example, if a model who wishes to become a mother but fears that pregnancy and raising a baby will harm her career adopts a teenage girl, such adoption will not usually be perceived as altruistic behavior; Whereas if the reason for the adoption is empathy for the girl's suffering, this will often be interpreted as altruistic behavior. The question for discussion in this discourse, therefore, is not the question that the biologist will ask - whether the act of adoption is expected to reduce the amount of fertile offspring that the model will probably give birth to - but what are the motives for the model's behavior.

Despite the differences in the meaning of 'altruism' in biology and everyday language, Darwin, and many following him, made a close connection between moral altruism, biological altruism and the mechanism of natural selection. As will be clarified in the fourth chapter, the evolutionary debate preserves to this day echoes and echoes of the moral debate on altruism, egoism and the freedom to choose between them.

The biologist, who is not concerned with the morality of the living creature or its intentions, faces a different difficulty in his attempts to explain how cooperative traits are maintained in nature. Already in his first book, The Maker of the Revolution, Darwin noted that he encountered a 'special problem', which 'almost disproved my whole theory', when he tried to explain what goes on inside social ant nests. All the ants born in the nest are endowed with all the necessary reproductive organs, but during their maturation most of the workers help their mates as fighters, as food gatherers or as crafts for the queen's offspring, instead of raising their own offspring.
Darwin had trouble explaining how the same altruistic behavior is inherited from generation to generation if those altruistic individuals do not reproduce at all!? In a broader aspect, the question that bothered Darwin was: How will natural selection, according to the benefit of the individual, explain the existence of traits that are apparently harmful to the individual, and even explain it better than the explanation that was accepted in nineteenth-century Europe, i.e. a purposeful mechanism whose end is predetermined (for the most part) by God (and there is no change in it from generation to generation. For a brief moment the theory of natural selection itself faced extinction, and this, even before it was officially born.

The problem is indeed troubling as long as it is assumed that natural selection operates only on the level of organization of individuals, i.e. organisms. In the bulk of Darwin's famous book, 'The Origin of Species', the organism is indeed the sole unit on which the pressure of natural selection acts, because the organism alone is born, produces offspring and dies. However, from the very definition of the concept of altruism it follows that an altruistic individual reproduces less than its fellows, therefore during evolution the altruistic trait should gradually disappear from the population. However, observations show that altruistic traits, at least in appearance, are very common in nature. As mentioned, it is difficult to explain the phenomenon through selection at the individual level, so Darwin turned to selection at the group level as an explanation for the evolution of altruism among ants.

If the competition between social groups is more intense than the competition within the groups, and if there is a distinct advantage to the group whose members do not produce offspring but, as in this example, specialize in the roles of artists or warriors - then the pressure of natural selection will lead to the spread of the trait of protecting and caring for the queen's offspring instead of producing
offspring. Explaining altruism through group-level selection was most popular until the first half of the twentieth century. In fact, group selection was almost the default explanation for any phenomenon that seemed harmful to an individual. But towards the end of the XNUMXs and during the XNUMXs, a new candidate for the screening unit for altruism burst onto the scene: the gene for the altruistic trait.

Protect altruism

First I will try to protect the garden. According to the approach that supports the theory of selection at the gene level, people do tend to focus on the obvious trait, the phenotype, but the genes are responsible for the appearance of the different phenotypes, and natural selection sifts between the different genes that cause different phenotypes with different abilities. 5 Therefore, the explanation for the spread of altruistic behavior in the population must first be sought in the gene for altruism and in the evolutionary response to the selection of that gene. Instead of asking how organisms compete, communicate or cooperate, or how groups and species change in different environments, one must examine how the gene competes and communicates with other genes and reacts to different genetic environments, that is, to different organisms in which it resides. The garden is the real selection unit.

This is the position of Richard Dawkins, perhaps the most well-known researcher among the general public, thanks to his vigorous defense of the theory of evolution in general and of selection at the kindergarten level in particular. Dawkins was born in Nairobi, Kenya, where his family moved during World War II. From his childhood home on the banks of the Mbagati River he may have heard the howls of jackals and hyenas, but he was spared the sirens of bombed London. Shortly after the end of the war, the family returned to England, and eight-year-old Richard joined the usual path for his status: a private school during the elementary and high school years, and Oxbridge (Cambridge or Oxford) afterwards. At the University of Oxford, Dawkins specialized in zoology,

and developed particularly close ties with his mentor, the Nobel Prize winner, Nikolaas Tinbergen (1907-1988). Although he also engaged in experiments and observations on chickens, Dawkins gained most of his publicity and success thanks to the brilliant popular science books he wrote on the subject of evolution. Today, Dawkins still He teaches at Oxford, as the head of the chair for 'Bringing science to the public', which was created especially for him. His books are indeed addressed to the general public, but they also receive an echo and a lively discussion among professional biologists.

One of the prominent evolution researchers who supported Dawkins' formulations is John Maynard Smith (1920-2004). John Maynard Smith died at the age of 84, while he was still in his full power: researcher, writer and above all - thinker. In his many articles, Maynard emphasized Smith repeatedly stressed the critical value of a full evolutionary response to natural selection. Any response to natural selection requires the inheritance of the selected trait (phenotype). However, Maynard Smith made it clear that an organism that reproduces through sexual reproduction has an average chance of only 50% of passing on its traits to the next generation, Because the other parent (the spouse) also has the same chance (50%) of inheriting his own traits.

If so, there is no certain inheritance for the trait of an organism, and even more so there is no certain inheritance or exact inheritance for the trait of a group of organisms. Groups are usually dispersed or distributed irregularly, so a group trait, such as the average number of altruistic individuals in a group, has an even smaller chance of replicating from the parent group to the daughter group. In fact, only a change in the gene may bring about an evolutionary change, because only the gene bequeaths its structure precisely and stable enough from generation to generation.

John Maynard Smith was born in London in 1920, to a family from a socio-economic background similar to that of his young friend, Dawkins. Maynard Smith also spent his youth at a private school (Eton boarding school) and soon after enrolled in engineering studies at Cambridge University. In those years - like quite a few good young men - Maynard Smith was attracted to the communist idea, and like his charismatic doctoral supervisor, JBS Haldane, 1892-1964 (), he also registered as a member of the party. But like few of his party members, He tried—and failed—to be accepted as a soldier in Her Majesty's Army in 1939 (immediately with the outbreak of the 'imperialist war', as his friends contemptuously called World War II).

Later, Maynard Smith joined the criticism of Moro and Rebbe Haldein on the genetics of the Lysenko-style Soviet school, and finally, following the Soviet invasion of Hungary, canceled his membership in the party. His work as an aeronautical engineer bored him and therefore, with the end of the war, he re-enrolled in studies, this time in zoology. Now Maynard Smith was able to combine his two loves in his work: mathematical models and observations of nature. John was a passionate nature lover and an expert ornithologist, but in any case of an apparent discrepancy between the observation and the mathematical model, his preference for a theory was clear: in his opinion, such a discrepancy requires, first of all, a re-examination of the description of the observation. In our case, he assumed that since, according to the model, in competition between groups, the altruistic trait will not be able to be inherited in most cases to other groups, and within the group it is always better to be among the receivers and not among the givers, then what seems to us to be altruistic behavior is, most likely, something else.

To the book page on the Magnes Publishing website, including the possibility of purchasing it