Social Evolution

 

                                                            Robert Trivers

 

I dabbled in several disciplines, but found myself disappointed in each. History, political science, economics, and psychology all expressed interesting views on human behavior, but none of these views seemed to have a secure foundation in pre-existing knowledge. For example, Western economics usually assumes that individuals are out to maximize personal gain, but where is the scientific justification for this assumption? And what is exactly “personal gain”? Much of psychology at the time assumed that human behavior is built entirely from learning experiences and that a theory of learning is the actual basis for any theory of human behavior. But psychology could give no coherent account of how these learning abilities are organized in us and toward what end we are learning what we are learning. (p. 1)

Our attention is focused on  variability within a population. We wish to see how variability in the traits of individuals is associated with variability in reproductive success. This represents an important break with pre-Darwinian biology. In the old system, each species was imagined to have been created according to some ideal type. Variation was just so much noise superimposed on the ideal type. After Darwin, the variation itself was seen as real and important, while the notion of an ideal type was recognized as a useless abstraction. (p. 22)

 

 

Since traits are only defined as useful by reference to a given environment, the concept of natural selection provides no objective support for terms like "higher" or "lower". ... The chief effect of using terms like "higher" and "lower" is to underestimate the powers of other creatures; "lower" animals, for example, are often assumed to be too dumb to act in their own self-interest. Unfortunately, this assumption --- often unconscious --- merely blinds us to the true nature of these creatures. (p. 32)

 

In the fall mating season, males fight with each other to control mating access to groups of females. During this time, the frequency of fighting and the number of injuries sustained is positively associated with the frequency with which females are conceiving. Just like the piglets in Figure 2-3, red deer males appear to adjust their aggressiveness to the value of the prize being fought for. (p. 36)

 

Comments: Why it is so peaceful here? Probably there is no much valuable to fight for.

 

 

 

All creatures must consume something of value in order to live and must consume more in order to grow and reproduce. This consumption is often at the expense of other members of the same species, so that even staying alive may, in effect, be a selfish act. Reproduction, in turn, is intrinsically social --- genes and energy are invested in the production of others --- and in many species this also requires the cooperation of two individuals (male and female). (p. 64)

 

From these observations, it seems likely that weaning conflict among monkeys is a costly process for the infants, its mother, and possibly for other troop members. Certainly the daily harassment of mother is costly in energy to infant and mother. The calls themselves may bring on predators and threaten the entire troop. Why, then, do we witness such intense parent --- offspring conflict in nature? (p. 146)

Comments: This applies to infant industry as well.

Another popular view is a fundamental conflict between biology and culture. The baby is viewed as innate selfish and greedy and in need of socialization in order to become a full culture-bearing creature. (p. 147)

Comments: in social sciences, people often argue the same line that human beings are cultured and hence biological explanations don’t always apply. But sociobiology is developed to under social behaviors with biological theory

 

Thus there is an overlap in self-interest between parent and offspring, but not an identity of self-interest. (p. 148)

Comment: This can explain most social behaviors.

 

Some people are reluctant to admit to biological differences between the human sexes. They grant that menstruation, gestation, and lactation belong to women and ejaculation to men, but beyond this they believe the sexes are essentially identical. Some of this view is undoubtedly a response to centuries of claims that women were biologically inferior and that  men were created or selected at the level of the species to perform wonderful, higher-level functions denied to women. The approach taken in this book gives no support for the notion of biological inferiority. Each sex, far from having evolved traits at the level of the species, is governed by individual reproductive advantage, sometimes in conflict with that of the other, and sex differences evolved because of an underlying differences in the work each invests --- or fails to invest --- in the raising of the offspring. If anything, male traits now threaten human species survival, since the potentially high reproductive success of males more easily tempts them into policies of aggression and aggrandizement. (p. 301)

 

In mammals and reptiles, males are usually XY and females XX, and males suffer higher mortality than do females. In fish, however, both sexes are usually XX and yet males still suffer higher mortality. In birds, females are XY and males XX, yet males still suffer higher mortality rates in those species of birds that lack male parental investment. (p. 307)

 

Comments: I read that in birds, females disperse more than males. Is that because females are XY and males are XX. Read more.

 

The most obvious effect of sex is the production of genetically variable offspring. A sexual reproduction usually results in offspring that are genetically identical copies of their mothers, but sex, through meiosis and recombination, gives rise to a wide array of genetically unique offspring. There must be some positive value associated with the production of genetic variability, but what exactly is it? (p. 315)

 

Comments: The advantage of genetic variability can be used to argue against the idea of general equilibrium theory. We also can argue against the pursuit to rate of growth in economic activities. Asexual reproduction is much faster over short term. We can understand social patterns in environments where population density is low and high. In places where population density is low, marriages between genetically and culturally close people may generate high rate of growth in population. But in densely populated environment, cross ethnic and cultural relations may benefit more. I have to think more about it.  

 

One of the most important things to realize about systems of animal communication is that they are not systems for the dissemination of the truth. An animal may be selected to convey correct information, misinformation, or both. ...  With powers to deceive and to spot deception being improved by natural selection, a new kind of deception may be favored: self-deception. Self deception renders the deception being practiced unconscious to the practioner, thereby hiding from other individuals the subtle signs of self-knowledge that give away the deception being practiced. (p. 395)

 

One particular consequence of deception deserves special attention: self-deception, that is hiding the truth from the conscious mind the better to hide it from others. In our own species we recognize that shifty eyes, sweaty palms, and croaky voices may indicate the stress that accompanies conscious knowledge of attempted deception. By becoming unconscious of its deception, the deceiver hides these signs from the observer. He or she can lie without the nervousness that accompanies deception. (p. 416)

 

In human evolution, process of deception and self-deception were greatly heightened by the advent of language. language permits individuals to make statements about events distant in time and space, and these are least amenable to contradiction. Thus language permits verbal deception of many different kinds. Since contradictory information is not available at the moment a deception is being practiced, there may be heightened attention to signs of conscious intent to deceive, and this will favor mechanisms of self-deception. ... individuals readily create entire belief systems with self serving biases, and the more skillfully these self-serving components are hidden from both the self and others, the more difficult it will be to counter them. (p. 416)

 

Self-confidence is a piece of information that may give useful information about the individual displaying it. If a male is facing off another male in an aggressive encounter, or is courting a female, he may be evaluated partly according to his self-confidence. A certain amount of self-deception in that situation may give a convincing image of his high self-esteem, thereby impressing others. (p. 416)

 

We tend to deny responsibility when we harm others. we either deny the harm or we deny that we ourselves are responsible. We have a tendency to exaggerate our own role in a beneficial outcome. For example, experiments in which groups of people are involved in a common task show that when group utcome is positive people evaluate their own contribution as a higher percentage of total effort than they contributed. And the reverse is true when the outcome is negative.

 

The tendency to deny responsibility for harmful outcomes sometimes takes the form of switching from an active to passive voice. If the outcome is good, then we played an active role; if it is bad, we were a passive victim of circumstances. (p. 419)

 

The illusion of consistency: ... This ploy was summarized by George Orwell in his novel 1984, while talking about leadership: "The secret of rulership is to combine a belief in one's own infallibility with a power to learn from past mistakes." (p. 419)