Information is typically packaged. The smallest unit of information (something like a bit) (see August 23, 2009 and August 17, 2009 posts) has limited meaning (information value) on its own. Aggregating, absorbing, connecting, colliding, and communicating with other units of information expands the information value associated with the package of bits. These packages of information include small subatomic units, electrons, atoms, chemical compounds, photons, waves of sound and light, proteins, genotypes, cells, organs, phenotypes, letters, words, songs, books, and culture. (See November 27, 2010 post).
Information migrates. (See May 20, 2012 post) It is in nearly constant motion. And when it is in motion, information can be altered and its meaning changed. (See August 15, 2011 and August 23, 2009 posts). Sometimes information is degraded by change; sometimes information is enhanced. Information moves with its package; the package migrates, and information moves along. Genes, Peoples and Languages is about the movement of genetic information in the package of a phenotype and the scientific quest to track the movement and transformation of modern human genes over the course of roughly one hundred thousand years. And along the way, as a result of natural selection, and in some geographic areas, genetic drift, the information in this genetic package was edited and revised from the general population that preceded it: hair texture and color changed, skin color changed, small genetic changes enabled humans to digest milk, immunized them from diseases such as malaria in certain areas, morphologies changed, and so on.
This research supports the Out of Africa hypothesis: that modern human origins begin on the African continent approximately 100,000 years ago, likely in southern Africa; that intra-continental African migration ensued northward along East Africa in the thousands of years afterward; and the first migration of homo sapiens out of Africa occurred roughly 50-60,000 years ago to the Arabian peninsula and the Levant, likely along the coast, and ultimately to southern Asia (India), southeast Asia, and Oceania (Australia) about 45,000 years ago. And about the same time that modern humans were reaching Oceania, migrations out of the Levant northward in the direction of Europe, and later in the direction of central Asia and ultimately to North America roughly 15,000 years ago. What should not be forgotten in this focus on modern human migration is that a similar migratory path may have been taken over a million years earlier by homo erectus.
Cavalli-Sforza sees a parallel between genetic evolution and cultural evolution. The units and type of information as well as the means of information transmission in these two circumstances, however, are radically different. Speech acts (including rituals) and language are the means of transmitting cultural information, and Cavalli-Sforza treats linguistic evolution as a type of cultural evolution. But genes and culture do not co-evolve. As mentioned in an earlier post, "Language is a social institution, and social institutions and culture evolve, albeit at a different and faster pace than biological evolution." (August 31, 2009 post). Language changes can occur as a result of migration and conquest of another's territory. Cavalli-Sforza documents this in a number of cases. Religion is another attribute of culture that likewise can change as a result of migration and conquest. (See May 12, 2010 post). And ideas can change as a result of migration and conquest. (See May 20, 2012 post). "There is a fundamental difference between biological and cultural mutation," writes Cavalli-Sforza. "Cultural mutations may result from random events, and thus be very similar to genetic mutations, but cultural changes are more often intentional or directed to a very specific goal, while biological mutations are blind to their potential benefit. At the level of mutation, cultural evolution can be directed while genetic change cannot." Later he adds, "We must note a significant difference between biological and linguistic mutation. A genetic mutant is generally very similar to the original gene, since one gives rise to another with only a small change. Words vary in more complicated ways. The same root can change meaning. One word can have may unrelated senses. One could try to establish greater similarities between genes and words taking into account all of the peculiarities, but it is not clear that would be useful." The curious aspect of Cavalli-Sforza's discussion of biological and cultural evolution and transmission is the absence of any discussion of the evolutionary debate about whether evolution operates on genes, phenotypes, or groups that has laced this subject for several decades now. (See November 4, 2009, November 30, 2009, September 12, 2012, and September 17, 2012 posts). References to Richard Dawkins, memes, and Edward Wilson are not to be found. Cavalli-Sforza's discussion on this subject is disjointed, and one wonders how he would treat the subject of the unit of information on which evolution operates.
Showing posts with label natural selection. Show all posts
Showing posts with label natural selection. Show all posts
Wednesday, September 25, 2013
Monday, September 17, 2012
Martin A. Nowak, SuperCooperators (2011)
In 2010, Martin Nowak collaborated with biologist Edward O. Wilson (see previous post) and mathematician Corina Tarnita in publishing an article in Nature entitled "The Evolution of Eusociality." The following year, Nowak followed the Nature article with SuperCooperators; two-years later, Wilson followed the Nature article with The Social Conquest of the Earth. The cornerstone of the Nature article was its criticism of the inclusive fitness theory, developed by William Hamilton and others, that became the mathematical foundation of kin selection in evolutionary analysis. Kin selection theory became the basis on which the presence of altruistic behavior in nature, a phenomenon noted by Darwin in The Origin of Species, could be explained in evolutionary terms. One would have thought from the Nature article that Nowak and Wilson were on the same page in terms of their analysis of evolution and cooperation, but the fact that they wrote separate follow-on books reveals significant differences. While Wilson creates controversy by announcing that he finds little additional value in kin selection theory for evolutionary analysis, Nowak acknowledges the detractors that responded to the Nature article and concludes that kin selection still has some explanatory value.
The discussion of group selection theory and multilevel selection with respect to the social insects in The Social Conquest of the Earth closely follows the summary of "a full theory of eusocial evolution" in the Nature article: "We suggest . . . the following may be recognized: (1) the formation of groups. (2) The occurrence of a minimum and necessary combination of pre-adaptive traits, causing the groups to be tightly formed. In animals at least, the combination includes a valuable and defensible nest. (3) The appearance of mutations that prescribe the persistence of the group, most likely by the silencing of dispersal behavior. Evidently, a durable nest remains a key element in maintaining the prevalence. Primitive eusociality may emerge immediately due to spring-loaded pre-adaptations. (4) Emergent traits caused by the interaction of group members are shaped through natural selection by environmental forces. (5) Multilevel selection drives changes in the colony life cycle and social structures, often to elaborate extremes. *** We have not addressed the evolution of human social behavior here, but parallels with the scenarios of animal eusocial evolution exist, and they are, we believe, well worth examining."
In their separate books, both Wilson and Nowak address "the evolution of human social behavior" not addressed in the Nature article, but they take divergent paths. Wilson starts to head down a path I wish he had developed further. To determine what evolved that made us humans, he begins by asking "What is human nature?" He suggests that the place to look is "in the rules of development prescribed by genes, through which the universals of culture are created." Human nature, he says, is the "inherited regularities of mental development common to our species. They are epigenetic rules, which evolved by the interaction of genetic and cultural evolution that occurred over a long period in deep prehistory. These rules are the genetic biases in the way our senses perceive the world, the symbolic coding by which we represent the world, the options we automatically open to ourselves, and the responses we find easiest and most rewarding to make. . . They determine the individuals we as a rule find sexually most attractive. They lead us differentially to acquire fears and phobias concerning dangers in the environment, as from snakes and heights, to communicate with certain facial expressions and forms of body language, to bond with infants; to bond conjugally; and so on across the wide range of other categories of behavior and thought." This is an important statement, but Wilson does not flesh it out, and he trips when he adds, "the rules of physiological development are not genetically hardwired." As Sean Carroll's Endless Forms Most Beautiful, The New Science of Evo-Devo explains, the developmental processes of different organisms are genetically determined, including the post-natal development of the organism, which in the case of humans goes on for many years. Wilson is simply wrong when he says that physiological development is "not beyond conscious control, like 'automatic' behaviors of heartbeat and breathing." He is wrong when he suggests that physiological development is completely "learned." Yes, there is a point when learning and culture become more influential, but as early (infant) child development research reports, the earliest form of social communication, mimicry, is instinctive, and it is not learned.
Wilson's reference to "physiological development" may simply be semantical error. Physiology broadly refers to "a branch of biology that deals with the functions and activities of life or of living matter (as organs, tissues, or cells) and of the physical and chemical phenomena involved—compare anatomy, morphology." Sean Carroll's discussion of evolutionary developmental biology focused primarily on morphology, although physiology is understood in its broader context as applicable to everything about living matter that has a genetic correlate. That would include the human brain and the neurosensory system. Wilson is thinking about something different than physiology. He is contemplating behavioral epigenetics, and refers to our innate predispositions to learn and make one choice over another. This is why understanding the human brain and the neurosensory system that feeds the human brain is critical to understanding human nature. Nor surprisingly, many posts on this blog are devoted to this understanding. Specifically, human behavior is not genetically determined, as social insect behavior might be genetically determined, but our nature has effectively set us up to receive information (learning, culture) in such a way that is more likely to cause us to behave one way rather than another. An example of this "predisposition" includes incest avoidance; we have a "bias" against sexual relations with those we have grown up in the same household.
In terms of social behavior, as I previously mentioned in the prior post I do not think we can understate the role of human memory --- unique in the animal kingdom --- in the evolution of culture. I also do not think we can understate the role of feelings and emotions either, and my surmise is that there is more than a predisposition here: human feelings and emotions are hardwired, and they likely contribute substantially to a number of our biases and predispositions. For example, feelings such as blushing are associated with social emotions such as shame and embarrassment. These emotions are universal among normal humans. It is surmised that blushing may have evolved as a means of avoiding conflict by reducing the possibility of deception. The person who witnesses another blush knows the reaction is authentic and that the person acknowledges he is troubled by what has happened. Disgust is another social emotion, likely to have evolved as a part of a physical response to offensive foods, is universal among normal humans. Wilson only briefly alludes to these basic social emotions, but significantly culture has evolved to exploit these emotions so the emotion can be triggered differently among different cultures. Nudity, for example, may trigger blushing in one culture,and no response in another. Fear, which Wilson briefly discusses, is another emotional response that has consequences for social behavior, is also exploited by culture. Feeling and emotion are central components of a biologically based understanding of morality, altruism and cooperative behavior. These emotions are also related to facial expressions that builds cooperative bonds, as observed by Paul Ekman and Dacher Keltner and reported in the discussion of Keltner's Born To Be Good: The Science of a Meaningful Life (see July 16, 2010 post):
"'Emotions are involuntary commitment devices that bind us to one another in long-term, mutually beneficial relationships,' Keltner says. Emotions are communicated through several sensory means: visually through facial expressions, which Keltner documents based on his own research and that of his teacher and mentor, Paul Ekman, explaining how muscles in the face are linked to and controlled by neural pathways in the brain that make them reliable indicators of emotion. In facial expression, we recognize embarrassment, which signals our moral sense of wrongdoing and respect for the judgment of others. In facial expression, the smile signals friendly intent and affection among peers and movement toward cooperation and intimacy. In facial expression, laughter triggers mirror neurons in the brains of others that builds cooperative bonds between one who laughs and the other who hears the laugh. Keltner tells us that teasing is not the same as bullying, and is a type of playful communication designed to ferret out another's commitments that bolsters social life. Emotions are communicated through touch, and the skin, our largest sensory organ, evolved to be an important part of social communication among humans and their predecessors."
Emotions also shape our reasoning, undermining the notion that we are purely rational animals.
(See April 8, 2011 post):
"Hume's treatment of emotions is not radically different than Damasio's, because Hume's catalog of emotions largely fall under the label of what Damasio refers to as the 'social emotions,' which Damasio believes are of recent evolutionary vintage, some of which may be exclusively human. For both Hume and Damasio, emotions shape our reasoning: 'rational' choice, if you will, is not independent of or from emotions and feelings. Compassion (empathy/sympathy) is one of those social emotions, and compassion, along with admiration, is critical in building a social construct in Damasio's view. And so it is with Hume, as Part III (On The Morals) states that sympathy with public interest is the source of moral approbation, and ultimately reciprocal promise-making behavior and principles of justice: 'sympathy is a very powerful principle in human nature, that it has great influence on our taste of beauty, and that it produces our sentiment of morals in all the artificial virtues.'"
Nowak, in contrast, is less concerned with the biological basis of social behavior, and he is more concerned with the conditions that make social cooperation more likely or less likely than not, and whether those conditions can be mathematically modeled (a game theoretic approach) and tested. Nowak finds that there are five "mechanisms" that explain whether social behavior is a likely trait that overcomes natural selection's inherent tendency to favor the individual pursuit of self-interest (cheating, defection). "[N]atural selection favors defectors [over cooperators] . . cooperators have a lower fitness than defectors in a well-mixed population. As a consequence, as that population evolves, natural selection slowly increases the abundance of defectors until every last one has been exterminated. This is the 'wrong' outcome, because a population of cooperators has a higher productivity (higher average fitness) than a population of defectors. Hence, in this particular case natural selection does not achieve the highest fitness but actually destroys what would be best for the entire population. To favor cooperation, natural selection needs help. It needs mechanisms for the evolution of cooperation. . . My work show how cooperation arises out of competition, even though the two are locked together in ceaseless conflict. The collective effort of society depends in part on suppressing the ability of the individual to mutiny and defect. The same goes for rebellious cells, chromosomes, and genes. Like day and night, or good and bad, cooperation and competition are forever entwined in a tight embrace."
The first of the five mechanisms of cooperation is direct reciprocity (backscratching) arising out of repetitive interaction. I will do a favor for another because I expect to encounter that person again and he will repay the favor. The second mechanism is indirect reciprocity, a reference to the reputation of the person or group (I will do you a favor, and by my reputation someone else will do me a favor). This type of reciprocity occurs without direct contact. The other person may be on another side of town or on the other side of the world. Indirect reciprocity relies heavily on communication to establish a reputation and language capacity is therefore important. The third mechanism is spatial selection, where natural selection favors individuals who form networks that help each other. The fourth mechanism is multilevel selection, where natural selection favors groups who are more successful in cooperating than other groups. The fifth mechanism is kin selection. With these five mechanisms of cooperation, "natural selection ensures that we are able to get more from social living than from the pursuit of a solitary, selfish life."
According to Nowak, what makes humans unique is that we are the only species on Earth that draws support from all five mechanisms of cooperation. We are the only species that "can summon the full power of indirect reciprocity, thanks to our rich and flexible language." That makes us "supercooperators." He adds, "We are now subject to an evolutionary dynamic that can detach itself to some degree from its genetic basis, from chemistry, genes, and DNA. This is cultural evolution, which involves learning, and explains why we are so devastatingly successful. As a result, the way the human brain evolves is utterly different from the evolution of any other biological structure that has ever existed. The architecture of the brain changes every time we talk to another person. We are able, in turn, to impose structural changes on the way the listener's brain is wired. The next time you listen to another person, remember that you have permanently changed the wiring of your brain and will do this every time you memorize a moment, no matter how fleeting." This remark recalls the discussion of how fragile memory is in the September 20, 2011 post discussing Daniel Schacter's The Seven Deadly Sins of Memory. Equally, however, Nowak demonstrates that notwithstanding a different attitude toward kin selection theory, he really is on the same page with Edward Wilson. "I do not restrict the use the term 'natural selection' to genes alone. Depending on whether we talk about cells, animals, or people, reproduction can be genetic or cultural." If we are speaking in terms of the fact that everything in life is reducible to a unit of information, I would agree that culture can be transmitted. (See August 15, 2011 post, August 17, 2009 post). And yes, cultures can die and disappear as a result of changes in the environment, as we saw in Jared Diamond's Collapse (see August 12, 2012 post), and Nowak echoes Diamond's concerns when he express concerns about "mankind teetering on the brink of several possible catastrophes of its own making," including nuclear conflagration and the ultimate "Tragedy of the Commons," global warming, which he believes will force humans to enter a new chapter of cooperation. The question, of course, is how long will take for humans to establish that level of consensus (see August 12, 2012 post). But I would echo Frans DeWaal: evolving culture in humans will not contradict what has evolved biologically, it will only support what evolved biologically.
The discussion of group selection theory and multilevel selection with respect to the social insects in The Social Conquest of the Earth closely follows the summary of "a full theory of eusocial evolution" in the Nature article: "We suggest . . . the following may be recognized: (1) the formation of groups. (2) The occurrence of a minimum and necessary combination of pre-adaptive traits, causing the groups to be tightly formed. In animals at least, the combination includes a valuable and defensible nest. (3) The appearance of mutations that prescribe the persistence of the group, most likely by the silencing of dispersal behavior. Evidently, a durable nest remains a key element in maintaining the prevalence. Primitive eusociality may emerge immediately due to spring-loaded pre-adaptations. (4) Emergent traits caused by the interaction of group members are shaped through natural selection by environmental forces. (5) Multilevel selection drives changes in the colony life cycle and social structures, often to elaborate extremes. *** We have not addressed the evolution of human social behavior here, but parallels with the scenarios of animal eusocial evolution exist, and they are, we believe, well worth examining."
In their separate books, both Wilson and Nowak address "the evolution of human social behavior" not addressed in the Nature article, but they take divergent paths. Wilson starts to head down a path I wish he had developed further. To determine what evolved that made us humans, he begins by asking "What is human nature?" He suggests that the place to look is "in the rules of development prescribed by genes, through which the universals of culture are created." Human nature, he says, is the "inherited regularities of mental development common to our species. They are epigenetic rules, which evolved by the interaction of genetic and cultural evolution that occurred over a long period in deep prehistory. These rules are the genetic biases in the way our senses perceive the world, the symbolic coding by which we represent the world, the options we automatically open to ourselves, and the responses we find easiest and most rewarding to make. . . They determine the individuals we as a rule find sexually most attractive. They lead us differentially to acquire fears and phobias concerning dangers in the environment, as from snakes and heights, to communicate with certain facial expressions and forms of body language, to bond with infants; to bond conjugally; and so on across the wide range of other categories of behavior and thought." This is an important statement, but Wilson does not flesh it out, and he trips when he adds, "the rules of physiological development are not genetically hardwired." As Sean Carroll's Endless Forms Most Beautiful, The New Science of Evo-Devo explains, the developmental processes of different organisms are genetically determined, including the post-natal development of the organism, which in the case of humans goes on for many years. Wilson is simply wrong when he says that physiological development is "not beyond conscious control, like 'automatic' behaviors of heartbeat and breathing." He is wrong when he suggests that physiological development is completely "learned." Yes, there is a point when learning and culture become more influential, but as early (infant) child development research reports, the earliest form of social communication, mimicry, is instinctive, and it is not learned.
Wilson's reference to "physiological development" may simply be semantical error. Physiology broadly refers to "a branch of biology that deals with the functions and activities of life or of living matter (as organs, tissues, or cells) and of the physical and chemical phenomena involved—compare anatomy, morphology." Sean Carroll's discussion of evolutionary developmental biology focused primarily on morphology, although physiology is understood in its broader context as applicable to everything about living matter that has a genetic correlate. That would include the human brain and the neurosensory system. Wilson is thinking about something different than physiology. He is contemplating behavioral epigenetics, and refers to our innate predispositions to learn and make one choice over another. This is why understanding the human brain and the neurosensory system that feeds the human brain is critical to understanding human nature. Nor surprisingly, many posts on this blog are devoted to this understanding. Specifically, human behavior is not genetically determined, as social insect behavior might be genetically determined, but our nature has effectively set us up to receive information (learning, culture) in such a way that is more likely to cause us to behave one way rather than another. An example of this "predisposition" includes incest avoidance; we have a "bias" against sexual relations with those we have grown up in the same household.
In terms of social behavior, as I previously mentioned in the prior post I do not think we can understate the role of human memory --- unique in the animal kingdom --- in the evolution of culture. I also do not think we can understate the role of feelings and emotions either, and my surmise is that there is more than a predisposition here: human feelings and emotions are hardwired, and they likely contribute substantially to a number of our biases and predispositions. For example, feelings such as blushing are associated with social emotions such as shame and embarrassment. These emotions are universal among normal humans. It is surmised that blushing may have evolved as a means of avoiding conflict by reducing the possibility of deception. The person who witnesses another blush knows the reaction is authentic and that the person acknowledges he is troubled by what has happened. Disgust is another social emotion, likely to have evolved as a part of a physical response to offensive foods, is universal among normal humans. Wilson only briefly alludes to these basic social emotions, but significantly culture has evolved to exploit these emotions so the emotion can be triggered differently among different cultures. Nudity, for example, may trigger blushing in one culture,and no response in another. Fear, which Wilson briefly discusses, is another emotional response that has consequences for social behavior, is also exploited by culture. Feeling and emotion are central components of a biologically based understanding of morality, altruism and cooperative behavior. These emotions are also related to facial expressions that builds cooperative bonds, as observed by Paul Ekman and Dacher Keltner and reported in the discussion of Keltner's Born To Be Good: The Science of a Meaningful Life (see July 16, 2010 post):
"'Emotions are involuntary commitment devices that bind us to one another in long-term, mutually beneficial relationships,' Keltner says. Emotions are communicated through several sensory means: visually through facial expressions, which Keltner documents based on his own research and that of his teacher and mentor, Paul Ekman, explaining how muscles in the face are linked to and controlled by neural pathways in the brain that make them reliable indicators of emotion. In facial expression, we recognize embarrassment, which signals our moral sense of wrongdoing and respect for the judgment of others. In facial expression, the smile signals friendly intent and affection among peers and movement toward cooperation and intimacy. In facial expression, laughter triggers mirror neurons in the brains of others that builds cooperative bonds between one who laughs and the other who hears the laugh. Keltner tells us that teasing is not the same as bullying, and is a type of playful communication designed to ferret out another's commitments that bolsters social life. Emotions are communicated through touch, and the skin, our largest sensory organ, evolved to be an important part of social communication among humans and their predecessors."
Emotions also shape our reasoning, undermining the notion that we are purely rational animals.
(See April 8, 2011 post):
"Hume's treatment of emotions is not radically different than Damasio's, because Hume's catalog of emotions largely fall under the label of what Damasio refers to as the 'social emotions,' which Damasio believes are of recent evolutionary vintage, some of which may be exclusively human. For both Hume and Damasio, emotions shape our reasoning: 'rational' choice, if you will, is not independent of or from emotions and feelings. Compassion (empathy/sympathy) is one of those social emotions, and compassion, along with admiration, is critical in building a social construct in Damasio's view. And so it is with Hume, as Part III (On The Morals) states that sympathy with public interest is the source of moral approbation, and ultimately reciprocal promise-making behavior and principles of justice: 'sympathy is a very powerful principle in human nature, that it has great influence on our taste of beauty, and that it produces our sentiment of morals in all the artificial virtues.'"
Nowak, in contrast, is less concerned with the biological basis of social behavior, and he is more concerned with the conditions that make social cooperation more likely or less likely than not, and whether those conditions can be mathematically modeled (a game theoretic approach) and tested. Nowak finds that there are five "mechanisms" that explain whether social behavior is a likely trait that overcomes natural selection's inherent tendency to favor the individual pursuit of self-interest (cheating, defection). "[N]atural selection favors defectors [over cooperators] . . cooperators have a lower fitness than defectors in a well-mixed population. As a consequence, as that population evolves, natural selection slowly increases the abundance of defectors until every last one has been exterminated. This is the 'wrong' outcome, because a population of cooperators has a higher productivity (higher average fitness) than a population of defectors. Hence, in this particular case natural selection does not achieve the highest fitness but actually destroys what would be best for the entire population. To favor cooperation, natural selection needs help. It needs mechanisms for the evolution of cooperation. . . My work show how cooperation arises out of competition, even though the two are locked together in ceaseless conflict. The collective effort of society depends in part on suppressing the ability of the individual to mutiny and defect. The same goes for rebellious cells, chromosomes, and genes. Like day and night, or good and bad, cooperation and competition are forever entwined in a tight embrace."
The first of the five mechanisms of cooperation is direct reciprocity (backscratching) arising out of repetitive interaction. I will do a favor for another because I expect to encounter that person again and he will repay the favor. The second mechanism is indirect reciprocity, a reference to the reputation of the person or group (I will do you a favor, and by my reputation someone else will do me a favor). This type of reciprocity occurs without direct contact. The other person may be on another side of town or on the other side of the world. Indirect reciprocity relies heavily on communication to establish a reputation and language capacity is therefore important. The third mechanism is spatial selection, where natural selection favors individuals who form networks that help each other. The fourth mechanism is multilevel selection, where natural selection favors groups who are more successful in cooperating than other groups. The fifth mechanism is kin selection. With these five mechanisms of cooperation, "natural selection ensures that we are able to get more from social living than from the pursuit of a solitary, selfish life."
According to Nowak, what makes humans unique is that we are the only species on Earth that draws support from all five mechanisms of cooperation. We are the only species that "can summon the full power of indirect reciprocity, thanks to our rich and flexible language." That makes us "supercooperators." He adds, "We are now subject to an evolutionary dynamic that can detach itself to some degree from its genetic basis, from chemistry, genes, and DNA. This is cultural evolution, which involves learning, and explains why we are so devastatingly successful. As a result, the way the human brain evolves is utterly different from the evolution of any other biological structure that has ever existed. The architecture of the brain changes every time we talk to another person. We are able, in turn, to impose structural changes on the way the listener's brain is wired. The next time you listen to another person, remember that you have permanently changed the wiring of your brain and will do this every time you memorize a moment, no matter how fleeting." This remark recalls the discussion of how fragile memory is in the September 20, 2011 post discussing Daniel Schacter's The Seven Deadly Sins of Memory. Equally, however, Nowak demonstrates that notwithstanding a different attitude toward kin selection theory, he really is on the same page with Edward Wilson. "I do not restrict the use the term 'natural selection' to genes alone. Depending on whether we talk about cells, animals, or people, reproduction can be genetic or cultural." If we are speaking in terms of the fact that everything in life is reducible to a unit of information, I would agree that culture can be transmitted. (See August 15, 2011 post, August 17, 2009 post). And yes, cultures can die and disappear as a result of changes in the environment, as we saw in Jared Diamond's Collapse (see August 12, 2012 post), and Nowak echoes Diamond's concerns when he express concerns about "mankind teetering on the brink of several possible catastrophes of its own making," including nuclear conflagration and the ultimate "Tragedy of the Commons," global warming, which he believes will force humans to enter a new chapter of cooperation. The question, of course, is how long will take for humans to establish that level of consensus (see August 12, 2012 post). But I would echo Frans DeWaal: evolving culture in humans will not contradict what has evolved biologically, it will only support what evolved biologically.
Wednesday, September 12, 2012
Edward O. Wilson, The Social Conquest of Earth (2012)
We tend to think of evolution in terms of a struggle, a "competitive struggle" in which natural selection favors certain genes, or a collection of genes in a particular organism for continued reproduction and survival. It is adaptation, however, not necessarily competition, that explains survival, and evolutionary theorists commonly explain adaptation in terms of self-interest. In Richard Dawkins' view, for example, genes are "selfish." In nature, however, evolution has favored a rare condition, "eusociality" in a handful of species, who in many respects have come to dominate the earth. As described by biologist Edward O. Wilson, eusociality refers to the "condition of multiple generations organized into groups by means of altruistic division of labor." The social insects --- wasps, ants, termites, bees, and a small number of other insect species --- are the most prominent examples of eusociality. The biomass of ants, for example, exceeds over half of all insects as well as the biomass of all non-human terrestrial vertebrates. Another prominent example, yet very different from the social insect, is the homo sapien.
Eusociality is characterized by a high level of cooperation, but it is important to note that cooperation is only a necessary, but not a sufficient condition for eusociality. We can think of many other examples in the animal kingdom, including symbiosis, multiple forms of reciprocal behavior, parenting, that do not rise to "multiple generations organized into groups by means of an altruistic division of labor." The definition of eusociality is a tight definition; it is not intended to capture all cooperative behavior in the animal kingdom that might be deemed "social." Eusociality does not describe herds, packs, dens, prides, or other groups animals who exhibit social behavior, because their social condition is not composed of multiple generations or their means of organization does not constitute an altruistic division of labor. Our closest living species, the chimpanzee, who exhibits social behavior (see November 9, 2010 post and June 17, 2010 post) is not considered eusocial.
In the world of social insects, the group is organized around the nest (or hive). In all of the examples of species that have attained eusociality, altruistic cooperation, says Wilson, protects a "persistent, defensible nest from its enemies, whether predators, parasites, or competitors," which sets the stage for members of a group belonging to more than one generation to divide labor in a way that sacrifices at least some of their selfish interests to the group. Importantly, multiple generations within the nest stay with the nest. They do not disperse.
While it is not yet proven, Wilson believes that eusociality in the social insects is genetically driven by a gene that silences the insect brain's program for dispersal and prevents the mother and her offspring from dispersing to create new nests, allowing natural selection on the rest of the genome to effectuate more complex forms of social organization. This occurs, says Wilson, because natural selection impacts not only the genotype (gene selection), but it also operates on groups within a species as well (group selection). This is the multi-level selection thesis previously discussed in the prior posting on Holldobler and Wilson's Superorganism (see November 4, 2009 post). The new twist in The Social Conquest of Earth is Wilson's declaration that kin selection, a form of group selection, can no longer be defended because its mathematical underpinning, inclusive fitness theory, had been debunked in a 2010 article co-authored by Wilson, Corina Tarnita, and Martin Nowak. The work of Bill Hamilton and George Price (see October 13, 2010 post), he contends, no longer contributes much to evolutionary analysis.
While multilevel selection remains a significant storyline in The Social Conquest of Earth, the biology of eusocial insects is merely a starting point for the discussion here. Wilson's focus is the homo sapien, humanity, and human nature, explaining his views of how eusociality evolved in homo sapiens. In contrast to the social insects, humans do not congregate in a nest. In contrast to the social insects, humans do disperse. But humans do build and maintain social communities comprised of multiple generations and, Bernard Mandeville's Fable of the Bees notwithstanding (see January 30, 2010 post), humans are organized into groups by altruistic division of labor. For Wilson, the social evolution of humans is not attributable to a single or "major" event such as the development of enlarged brains or bi-pedal mobility, but can only be understood in terms of prehuman adaptations in ancient species and adaptations that distinguish humans from other hominids, evidence from human archaeology, and the co-evolution of human culture, all of which have come to define "human nature." Wilson is a proponent of the "dual inheritance theory." For Wilson, a key event in human history is technological: the mastery of fire. With the ability to control fire, campfires are created and the campfire, in Wilson's view, is the homo sapiens' counterpart of the insect nest. Campfires are the venue that facilitates the sharing of food, and this is the magnet that draws homo sapiens into a cooperative environment.
In my November 4, 2009 post, I commented on Holldobler and Wilson's discussion of multilevel selection as follows: "However powerful the evidence for the superorganism is and the multilevel selection model, the truth remains that the critical unit of evolution is the gene." I made have overstated the uniqueness of the gene in making this statement and uninentionally sublimated the individual: after all, it is the individual (a collection of genes) that reproduces. A comment I made in the November 9, 2010 post discussing Frans DeWaal's The Age of Empathy seems extremely relevant: "Our capacity for cooperation, altruism, and other social instincts is certainly biological, and it is a product of evolution. We have much to learn about what makes us human from learning about the behavior of other species from which humans evolved as we do from observing our own behavior. This is De Waal's primary thesis. And this thesis is no stranger to this blog and previous posts, including De Waal's own The Ape and the Sushi Master (June 17, 2010 post), Oren Harman's The Price of Altruism (October 13, 2010 post), Dacher Keltner's Born to Be Good (July 16, 2010 post), Holldobler and Wilson's The Superorganism (November 4, 2009 post), Michael Gazzaniga's Human (September 27, 2009), Marco Iacobonni's Mirroring People (September 18, 2009 post), and Christine Kennealy's The First Word (August 31, 2009 post)." Natural selection operates on what is biological or chemical; while culture undeniably "evolves," natural selection as we understand it does not operate upon culture. If culture is going to be successful, it is because it supports what natural selection favors. As Frans DeWaal explains in the The Ape and The Sushi Master: "Although the relation between culture and nature can be tense, culture mostly tries to get along with nature." Culture cannot change nature; culture can evolve behavior to act consistently with nature. For example, the incest taboo - an avoidance of sex among family members, long a cultural regulation, is now known to be a form of behavior in the primate world that appears to be innate in some aspects (an aversion rather than an avoidance) and perhaps learned in other respect. (See June 17, 2010 post)." Group selection and multilevel selection are not settled theories, and Wilson's rejection of kin selection is contested by others in the field.
Wilson's discussion of "group selection" suggests that evolution operates at the level of a group within a species. Thus a "group" might be a nation or a religious group or an ethnic group in the case of humans, and here I part company with Wilson . These are cultural groups, and natural selection does not operate upon culture. When I thought about how I would respond to Wilson's discussion here, I realized I had already said in my discussions of Frans DeWaal's The Age of Empathy (November 9, 2010 post) and The Ape and the Sushi Master (June 17, 2010 post) what I want to say (and what DeWaals has to say) about the linkage between genes and culture in those posts. Here is a snippet from the June 17, 2010 post:
"Culture and genetics have one thing in common --- the transmission of information: in the case of genetics information is transmitted by biological/chemical means, in the case of culture it is transmitted by social means. 'This is not to say that both forms of behavioral inheritance --- the one traveling across time via genotypes, the other via phenotypes --- should not or could not be conceptually linked. Ironically, the Lamarckian idea that acquired characteristics can be inherited has found its realization not in the physical characteristics he was thinking of, but in behavior. Genetic predispositions feed into culture, culture affects survival, and survival and reproduction determine which genotypes spread in the population. In other words, there exists a dauntingly complex interplay between genetic and cultural transmission. Brave and inspiring attempts at a theory of dual inheritance, or co evolution, have been made, without, however, in any way confusing the two processes.'" Wilson confuses the two processes. I would have liked to see in his discussion of human evolution and our predisposition to social behavior a more biologically-based discussion of the neurological system and human child development, such as that in the November 9, 2010 post about The Age of Empathy:
"At the biological core of our humanness is the limbic system, which, from an evolutionary perspective, is one of the oldest parts of our neural network in the human brain. It is a part of the brains of other species as well. Antonio Damassio identifies the limbic system as a critical regulator of feelings and emotions in The Feeling of What Happens, and it is central to understanding human consciousness. De Waal says the limbic system allows emotions such as affection and pleasure, and paved the way for family life, friendships, and other caring relationships. Other parts of our neural network allow us to store memories of these feelings and emotions and allow us to recall the context in which we previously experienced them and then to "understand" them. A key line here is De Waal's statement, "Bodily connections come first --- understanding follows." Mirror neurons, as described in Iacobonni's Mirroring People (September 18, 2009 post), are active in these other parts of the neural network known as the brain that allow us to "read" the minds of others, enabling us to connect with others, and facilitate the the experience we call empathy. "De Waal calls this emotional contagion: seeing another's emotions arouses our own emotions, and then we build "a more advanced understanding of another's situation." Later, he adds, "Empathy engages brain areas that are more than a hundred million years old. The capacity arose long ago with motor mimicry and emotional contagion, after which evolution added layer after layer, until our ancestors not only felt what others felt, but understood what others might want or need."
"True to his dualism, just as De Waal recognizes that emotional contagion probably starts immediately with the mother-child relationship and that early communication fosters a bond, a second phase begins just months later in the course of child development when the child begins to develop a sense of self. And empathy, De Waal believes, "requires both mental mirroring and mental separation." The former occurs when we see another person in a particular emotional state. The latter occurs when we parse our own emotional state from the other, and this allows us to "pinpoint the actual source of our own feelings." De Waal attributes our dualism to the existence of VEN cells in the brain --- Von Economo neurons --- that differ from other neurons and are unique to humans and their recent ancestors. Physically, VEN cells are long and spindle-like and reach deeper into the brain. Research shows that when parts of the human brain that contain these cells are damaged, behavior is marked by a loss of perspective-taking, empathy, embarrassment, and future orientation. Besides humans and certain apes, these cells are also found in dolphins, whales, and elephants, where behavioral research shows they have the capacity for empathy that is not found in other species."
Some of this is touched upon by Wilson, but what is touched upon deserves elaboration and much is missing from The Social Conquest of Earth. Yet these biological attributes of homo sapiens are the products of natural selection in humans and they specifically relate to our ability to act cooperatively and altruistically: the neurobiology behind feelings and emotions (see April 8, 2011 post), the neurobiology behind memory (see April 8, 2011 post and November 6, 2011 post, and September 20, 2011 post), the neurobiology behind our sensory system and our ability to communicate and our capacity for storytelling (see October 25, 2011 post, September 27, 2009 post, and August 31, 2009 post), and the biology of human development. For example, we cannot underestimate the role of human memory (including the failings of memory, see September 20, 2011 post) in evolving a human culture, and several prior posts have addressed this subject in one way or the another. (See September 28, 2010 post, September 9, 2010 post, and August 15, 2011 post) Wilson merely summarizes these attributes when he notes:
"What catapulted Home sapiens to this level? Experts on the subject agree that increased long-term memory, expecially that put into working memory, and with it an ability to construct scenarios and plan strategy in brief periods of time, played the key role in Europe and elsewhere, both before the African breakout and afterward. What was the driving force that led to the threshold of complex culture? It appears to have been group selection. A group with members who could read intentions and cooperate among themselves while predicting the actions of competing groups, would have an enormous advantage over others less gifted. . . Morality, conformity, religious fervor, and fighting ability combined with imagination and memory to produce the winner."
These are the human attributes that are genetically determined by evolution, and they are the biological basis of humanity. Our social instincts are derived from these biological attributes.
Notwithstanding my conclusion that much is missing from The Social Conquest of the Earth, Wilson's discussion of the origins of religion and organized religion and the origins of the creative arts are brilliant. These subjects too have been the topics of prior posts. (See January 14, 2012 post, February 4, 2012 post, February 15, 2012 post, and June 12, 2011 post).
Eusociality is characterized by a high level of cooperation, but it is important to note that cooperation is only a necessary, but not a sufficient condition for eusociality. We can think of many other examples in the animal kingdom, including symbiosis, multiple forms of reciprocal behavior, parenting, that do not rise to "multiple generations organized into groups by means of an altruistic division of labor." The definition of eusociality is a tight definition; it is not intended to capture all cooperative behavior in the animal kingdom that might be deemed "social." Eusociality does not describe herds, packs, dens, prides, or other groups animals who exhibit social behavior, because their social condition is not composed of multiple generations or their means of organization does not constitute an altruistic division of labor. Our closest living species, the chimpanzee, who exhibits social behavior (see November 9, 2010 post and June 17, 2010 post) is not considered eusocial.
In the world of social insects, the group is organized around the nest (or hive). In all of the examples of species that have attained eusociality, altruistic cooperation, says Wilson, protects a "persistent, defensible nest from its enemies, whether predators, parasites, or competitors," which sets the stage for members of a group belonging to more than one generation to divide labor in a way that sacrifices at least some of their selfish interests to the group. Importantly, multiple generations within the nest stay with the nest. They do not disperse.
While it is not yet proven, Wilson believes that eusociality in the social insects is genetically driven by a gene that silences the insect brain's program for dispersal and prevents the mother and her offspring from dispersing to create new nests, allowing natural selection on the rest of the genome to effectuate more complex forms of social organization. This occurs, says Wilson, because natural selection impacts not only the genotype (gene selection), but it also operates on groups within a species as well (group selection). This is the multi-level selection thesis previously discussed in the prior posting on Holldobler and Wilson's Superorganism (see November 4, 2009 post). The new twist in The Social Conquest of Earth is Wilson's declaration that kin selection, a form of group selection, can no longer be defended because its mathematical underpinning, inclusive fitness theory, had been debunked in a 2010 article co-authored by Wilson, Corina Tarnita, and Martin Nowak. The work of Bill Hamilton and George Price (see October 13, 2010 post), he contends, no longer contributes much to evolutionary analysis.
While multilevel selection remains a significant storyline in The Social Conquest of Earth, the biology of eusocial insects is merely a starting point for the discussion here. Wilson's focus is the homo sapien, humanity, and human nature, explaining his views of how eusociality evolved in homo sapiens. In contrast to the social insects, humans do not congregate in a nest. In contrast to the social insects, humans do disperse. But humans do build and maintain social communities comprised of multiple generations and, Bernard Mandeville's Fable of the Bees notwithstanding (see January 30, 2010 post), humans are organized into groups by altruistic division of labor. For Wilson, the social evolution of humans is not attributable to a single or "major" event such as the development of enlarged brains or bi-pedal mobility, but can only be understood in terms of prehuman adaptations in ancient species and adaptations that distinguish humans from other hominids, evidence from human archaeology, and the co-evolution of human culture, all of which have come to define "human nature." Wilson is a proponent of the "dual inheritance theory." For Wilson, a key event in human history is technological: the mastery of fire. With the ability to control fire, campfires are created and the campfire, in Wilson's view, is the homo sapiens' counterpart of the insect nest. Campfires are the venue that facilitates the sharing of food, and this is the magnet that draws homo sapiens into a cooperative environment.
In my November 4, 2009 post, I commented on Holldobler and Wilson's discussion of multilevel selection as follows: "However powerful the evidence for the superorganism is and the multilevel selection model, the truth remains that the critical unit of evolution is the gene." I made have overstated the uniqueness of the gene in making this statement and uninentionally sublimated the individual: after all, it is the individual (a collection of genes) that reproduces. A comment I made in the November 9, 2010 post discussing Frans DeWaal's The Age of Empathy seems extremely relevant: "Our capacity for cooperation, altruism, and other social instincts is certainly biological, and it is a product of evolution. We have much to learn about what makes us human from learning about the behavior of other species from which humans evolved as we do from observing our own behavior. This is De Waal's primary thesis. And this thesis is no stranger to this blog and previous posts, including De Waal's own The Ape and the Sushi Master (June 17, 2010 post), Oren Harman's The Price of Altruism (October 13, 2010 post), Dacher Keltner's Born to Be Good (July 16, 2010 post), Holldobler and Wilson's The Superorganism (November 4, 2009 post), Michael Gazzaniga's Human (September 27, 2009), Marco Iacobonni's Mirroring People (September 18, 2009 post), and Christine Kennealy's The First Word (August 31, 2009 post)." Natural selection operates on what is biological or chemical; while culture undeniably "evolves," natural selection as we understand it does not operate upon culture. If culture is going to be successful, it is because it supports what natural selection favors. As Frans DeWaal explains in the The Ape and The Sushi Master: "Although the relation between culture and nature can be tense, culture mostly tries to get along with nature." Culture cannot change nature; culture can evolve behavior to act consistently with nature. For example, the incest taboo - an avoidance of sex among family members, long a cultural regulation, is now known to be a form of behavior in the primate world that appears to be innate in some aspects (an aversion rather than an avoidance) and perhaps learned in other respect. (See June 17, 2010 post)." Group selection and multilevel selection are not settled theories, and Wilson's rejection of kin selection is contested by others in the field.
Wilson's discussion of "group selection" suggests that evolution operates at the level of a group within a species. Thus a "group" might be a nation or a religious group or an ethnic group in the case of humans, and here I part company with Wilson . These are cultural groups, and natural selection does not operate upon culture. When I thought about how I would respond to Wilson's discussion here, I realized I had already said in my discussions of Frans DeWaal's The Age of Empathy (November 9, 2010 post) and The Ape and the Sushi Master (June 17, 2010 post) what I want to say (and what DeWaals has to say) about the linkage between genes and culture in those posts. Here is a snippet from the June 17, 2010 post:
"Culture and genetics have one thing in common --- the transmission of information: in the case of genetics information is transmitted by biological/chemical means, in the case of culture it is transmitted by social means. 'This is not to say that both forms of behavioral inheritance --- the one traveling across time via genotypes, the other via phenotypes --- should not or could not be conceptually linked. Ironically, the Lamarckian idea that acquired characteristics can be inherited has found its realization not in the physical characteristics he was thinking of, but in behavior. Genetic predispositions feed into culture, culture affects survival, and survival and reproduction determine which genotypes spread in the population. In other words, there exists a dauntingly complex interplay between genetic and cultural transmission. Brave and inspiring attempts at a theory of dual inheritance, or co evolution, have been made, without, however, in any way confusing the two processes.'" Wilson confuses the two processes. I would have liked to see in his discussion of human evolution and our predisposition to social behavior a more biologically-based discussion of the neurological system and human child development, such as that in the November 9, 2010 post about The Age of Empathy:
"At the biological core of our humanness is the limbic system, which, from an evolutionary perspective, is one of the oldest parts of our neural network in the human brain. It is a part of the brains of other species as well. Antonio Damassio identifies the limbic system as a critical regulator of feelings and emotions in The Feeling of What Happens, and it is central to understanding human consciousness. De Waal says the limbic system allows emotions such as affection and pleasure, and paved the way for family life, friendships, and other caring relationships. Other parts of our neural network allow us to store memories of these feelings and emotions and allow us to recall the context in which we previously experienced them and then to "understand" them. A key line here is De Waal's statement, "Bodily connections come first --- understanding follows." Mirror neurons, as described in Iacobonni's Mirroring People (September 18, 2009 post), are active in these other parts of the neural network known as the brain that allow us to "read" the minds of others, enabling us to connect with others, and facilitate the the experience we call empathy. "De Waal calls this emotional contagion: seeing another's emotions arouses our own emotions, and then we build "a more advanced understanding of another's situation." Later, he adds, "Empathy engages brain areas that are more than a hundred million years old. The capacity arose long ago with motor mimicry and emotional contagion, after which evolution added layer after layer, until our ancestors not only felt what others felt, but understood what others might want or need."
"True to his dualism, just as De Waal recognizes that emotional contagion probably starts immediately with the mother-child relationship and that early communication fosters a bond, a second phase begins just months later in the course of child development when the child begins to develop a sense of self. And empathy, De Waal believes, "requires both mental mirroring and mental separation." The former occurs when we see another person in a particular emotional state. The latter occurs when we parse our own emotional state from the other, and this allows us to "pinpoint the actual source of our own feelings." De Waal attributes our dualism to the existence of VEN cells in the brain --- Von Economo neurons --- that differ from other neurons and are unique to humans and their recent ancestors. Physically, VEN cells are long and spindle-like and reach deeper into the brain. Research shows that when parts of the human brain that contain these cells are damaged, behavior is marked by a loss of perspective-taking, empathy, embarrassment, and future orientation. Besides humans and certain apes, these cells are also found in dolphins, whales, and elephants, where behavioral research shows they have the capacity for empathy that is not found in other species."
Some of this is touched upon by Wilson, but what is touched upon deserves elaboration and much is missing from The Social Conquest of Earth. Yet these biological attributes of homo sapiens are the products of natural selection in humans and they specifically relate to our ability to act cooperatively and altruistically: the neurobiology behind feelings and emotions (see April 8, 2011 post), the neurobiology behind memory (see April 8, 2011 post and November 6, 2011 post, and September 20, 2011 post), the neurobiology behind our sensory system and our ability to communicate and our capacity for storytelling (see October 25, 2011 post, September 27, 2009 post, and August 31, 2009 post), and the biology of human development. For example, we cannot underestimate the role of human memory (including the failings of memory, see September 20, 2011 post) in evolving a human culture, and several prior posts have addressed this subject in one way or the another. (See September 28, 2010 post, September 9, 2010 post, and August 15, 2011 post) Wilson merely summarizes these attributes when he notes:
"What catapulted Home sapiens to this level? Experts on the subject agree that increased long-term memory, expecially that put into working memory, and with it an ability to construct scenarios and plan strategy in brief periods of time, played the key role in Europe and elsewhere, both before the African breakout and afterward. What was the driving force that led to the threshold of complex culture? It appears to have been group selection. A group with members who could read intentions and cooperate among themselves while predicting the actions of competing groups, would have an enormous advantage over others less gifted. . . Morality, conformity, religious fervor, and fighting ability combined with imagination and memory to produce the winner."
These are the human attributes that are genetically determined by evolution, and they are the biological basis of humanity. Our social instincts are derived from these biological attributes.
Notwithstanding my conclusion that much is missing from The Social Conquest of the Earth, Wilson's discussion of the origins of religion and organized religion and the origins of the creative arts are brilliant. These subjects too have been the topics of prior posts. (See January 14, 2012 post, February 4, 2012 post, February 15, 2012 post, and June 12, 2011 post).
Wednesday, October 13, 2010
Oren Harman, The Price of Altruism (2010)
Is behavior genetically determined? This was a question that was posed in in Richard Powers' Generosity (see November 30, 2009 post), and the answer that still makes sense after reading the Price of Altruism is that specific behavior --- whether human or nonhuman --- is not genetic, but that the attrinutes that genes actually code for contain information that enable or predispose species to certain types of behavior. Environment and nurture (learning) transmit information to us as well --- above and beyond the information transmitted by genes --- and they also influence behavior.
The Price of Altruism is a wonderful title for this book --- a double entendre --- reflecting the author's mission to tell the story of one of the brightest persons of the 20th century that nobody really knew, George Price, and to tell the story of the efforts of numerous professionals in science and the social sciences to determine just who we humans are and how did we become who we are, a story that is told in various ways in a number of other books previously discussed in this blog. The behavioral mystery that George Price and the others whose intellectual pursuits paralleled that of Price --- including Bill Hamilton, John Maynard Smith, Robert Trivers, E.O. Wilson, Richard Dawkins, Frans deWaal, and others --- sought to unravel is why do humans behave altruistically, even if it means that the altruistic choice sacrifices the survival of the individual? In this context, the "price" of altruism refers to sacrifice, or alternatively, reciprocal exchanges that encourage cooperation rather than competition.
Central to this inquiry is whether "moral" behavior has a genetic origin, and, if so, what is the evolutionary mechanism that selects for moral behavior? Or is moral behavior the consequence of environment, and can humans and other animals shape their environment to yield a certain behavioral pattern?
George Price seemed the unlikeliest of persons to be a player in this inquiry. He cannot seem to devote himself to a single subject of interest for more than a year before moving onto the next. Price, a veritable Forrest Gump of intellectual inquiry --- he was involved with the Manhattan Project, could be found at Bell Labs at the time of the development of the transistor and knew Claude Shannon (see August 23, 2009 post), he developed something he called the Design Machine, a forerunner of CAD-CAM design software that led him briefly to work at IBM, and he dabbled in economics, game theory, and psychology (ESP), even though he had no training in those subjects either. Nothing seemed to intrigue him longer than a year or two and in his personal life he was simply not committed to anything, at least for any significant period of time. Price left the United States for London in 1967 with no particular goal in mind, until he became interested in the development of cooperative behavior. While in London, Price became familiar with William Hamilton's paper on "The Genetical Evolution of Social Behavior," another subject in which he had no formal training, which led him to begin corresponding with Hamilton. Soon Price was wading into the debate over whether natural selection operated on the level of the genotype, the phenotype, kin groups, or larger groups. (See November 4, 2009 post).
The big topic in this book is the relationship between the biological and evolutionary imperatives for reproduction and survival and a system of moral rules. Is selflessness --- altruistic behavior--- stronger because it is directed at close kin, or others in a close social community, or strangers? And is there a biological basis for altruistic behavior?
The contributions of George Price to the study of genetic evolution and kin selection theory and group selection are better described elsewhere. But the importance of Price's work and what he contributed to the work of others on this subject is summed up as follows:
"After all, the feeling that genes do not simply 'run the show' comports not only with our vanity but also with our exceedingly healthy intituion about reality, as well as with what science is teaching us. Of course Haldane, Maynard Smith, Hamilton, and Price knew this, too. For when they spoke of genes for altruism, they were really only using a shorthand for genes that increase the probability that their bearers will behave altruistically. So long as such behaviors have a heritable component, evolutionary reasoning applies. Despite the incautious remarks of scientists and, more often, of science writers this does not mean that a behavior is determined; culture and education are still acknowledged as playing a central, even exclusive role. There may be no behavior in humans, strictly speaking, that has no genetic component, but that's a world away from saying that our genes determine who we are and what we choose. As biologists and anthropologists and mathematicians and philosophers who study the subject have come to see, natural selection based on cultural variation has produced behaviors that have nothing to do directly with genes." [Emphasis supplied].
Harman's gift in this book is not just the biography of George Price, but also the intellectual heritage that both preceded and followed his life on the subject of the evolutionary origins of social behavior. Despite a 7-year long interest in this subject while in London, Price continued to divert his interest other interests. He "converted" from atheism to Christianity, and made a serious effort at trying to make his life more "Christ-like," which left him living among London's homeless and downtrodden, giving away what little assets he had to give to help others. He fell into a life poverty and sickness, and toward the end of his life appeared to contemplate that there may be more to life than altruism and sacrifice. He committed suicide in early January 1975.
The Price of Altruism is a wonderful title for this book --- a double entendre --- reflecting the author's mission to tell the story of one of the brightest persons of the 20th century that nobody really knew, George Price, and to tell the story of the efforts of numerous professionals in science and the social sciences to determine just who we humans are and how did we become who we are, a story that is told in various ways in a number of other books previously discussed in this blog. The behavioral mystery that George Price and the others whose intellectual pursuits paralleled that of Price --- including Bill Hamilton, John Maynard Smith, Robert Trivers, E.O. Wilson, Richard Dawkins, Frans deWaal, and others --- sought to unravel is why do humans behave altruistically, even if it means that the altruistic choice sacrifices the survival of the individual? In this context, the "price" of altruism refers to sacrifice, or alternatively, reciprocal exchanges that encourage cooperation rather than competition.
Central to this inquiry is whether "moral" behavior has a genetic origin, and, if so, what is the evolutionary mechanism that selects for moral behavior? Or is moral behavior the consequence of environment, and can humans and other animals shape their environment to yield a certain behavioral pattern?
George Price seemed the unlikeliest of persons to be a player in this inquiry. He cannot seem to devote himself to a single subject of interest for more than a year before moving onto the next. Price, a veritable Forrest Gump of intellectual inquiry --- he was involved with the Manhattan Project, could be found at Bell Labs at the time of the development of the transistor and knew Claude Shannon (see August 23, 2009 post), he developed something he called the Design Machine, a forerunner of CAD-CAM design software that led him briefly to work at IBM, and he dabbled in economics, game theory, and psychology (ESP), even though he had no training in those subjects either. Nothing seemed to intrigue him longer than a year or two and in his personal life he was simply not committed to anything, at least for any significant period of time. Price left the United States for London in 1967 with no particular goal in mind, until he became interested in the development of cooperative behavior. While in London, Price became familiar with William Hamilton's paper on "The Genetical Evolution of Social Behavior," another subject in which he had no formal training, which led him to begin corresponding with Hamilton. Soon Price was wading into the debate over whether natural selection operated on the level of the genotype, the phenotype, kin groups, or larger groups. (See November 4, 2009 post).
The big topic in this book is the relationship between the biological and evolutionary imperatives for reproduction and survival and a system of moral rules. Is selflessness --- altruistic behavior--- stronger because it is directed at close kin, or others in a close social community, or strangers? And is there a biological basis for altruistic behavior?
The contributions of George Price to the study of genetic evolution and kin selection theory and group selection are better described elsewhere. But the importance of Price's work and what he contributed to the work of others on this subject is summed up as follows:
"After all, the feeling that genes do not simply 'run the show' comports not only with our vanity but also with our exceedingly healthy intituion about reality, as well as with what science is teaching us. Of course Haldane, Maynard Smith, Hamilton, and Price knew this, too. For when they spoke of genes for altruism, they were really only using a shorthand for genes that increase the probability that their bearers will behave altruistically. So long as such behaviors have a heritable component, evolutionary reasoning applies. Despite the incautious remarks of scientists and, more often, of science writers this does not mean that a behavior is determined; culture and education are still acknowledged as playing a central, even exclusive role. There may be no behavior in humans, strictly speaking, that has no genetic component, but that's a world away from saying that our genes determine who we are and what we choose. As biologists and anthropologists and mathematicians and philosophers who study the subject have come to see, natural selection based on cultural variation has produced behaviors that have nothing to do directly with genes." [Emphasis supplied].
Harman's gift in this book is not just the biography of George Price, but also the intellectual heritage that both preceded and followed his life on the subject of the evolutionary origins of social behavior. Despite a 7-year long interest in this subject while in London, Price continued to divert his interest other interests. He "converted" from atheism to Christianity, and made a serious effort at trying to make his life more "Christ-like," which left him living among London's homeless and downtrodden, giving away what little assets he had to give to help others. He fell into a life poverty and sickness, and toward the end of his life appeared to contemplate that there may be more to life than altruism and sacrifice. He committed suicide in early January 1975.
Wednesday, November 4, 2009
Bert Hölldobler & E.O. Wilson, The Superorganism (2008)
Human (September 27 post), Mirroring People (September 18 post), and The First Word (August 31 post) all stress the social nature of the human species as something unique to homo sapiens. Marco Iaccoboni, as we saw in Mirroring People, believes that not enough weight is given to our social nature and too much consideration is given to our individuality. But what of other species? We know that other primates are social, although not to the extent of the human species. But there are other species who are even more socially organized than the human species. Meet the social insects --- bees, wasps, ants, termites --- who have established a diverse array of social communities, some of which have suppressed nearly all individuality.
Holldobler and Wilson's The Superorganism does not specifically address the big three areas of human inquiry -- the very large, the very small, and the human mind -- that I described in the August 31st post, but the book is devoted to that other question I mentioned: what is life? The subject-matter of The Superorganism is not entirely divorced from the books in the preceding posts. One of the links between each of the books reviewed in earlier posts is the subject of information and communication. The largest chapter of this beautiful book exhaustively summarizes what we know about communication within the species of the social insects --- not at the level of electrons and quarks and bosons that Seth Lloyd focused on --- but at the level of chemical compounds and the sensory capabilities of these insects: pheromones secreted to lay a trail for colony ants to follow leaders from the nest to food sources and back; odors of hydrocarbons that confirm the queen is present in the colony that shut down the reproductive capabilities of female workers so that only the queen becomes the source of eggs; odors of hydrocarbons that enable ants to distinguish members of their own colony from outsiders. There is also the suggestion, not inconsistent with Christine Keneally's statement in The First Word that human language is believed to have emerged from human motor skills, that insect communication may have emerged from the insect's motor skills.
But information is not the big idea in Superorganism. Information and communication among individual insects and competing groups of insects is just a significant piece of the evidence that supports the big idea in this book: multilevel natural selection. Since Richard Dawkins originally published The Selfish Gene in 1976, a debate has raged whether natural selection operates on genes, as advanced by Dawkins, or whether it operates on the individual organism (phenotype) --- the carrier of a collection of genes, or whether it operates on groups such as related kin, or more broadly communities or colonies. The advocates for each view were said to promote gene selection, individual selection, kin selection, or group selection respectively. Charles Darwin, because he lacked an understanding of Mendellian genetics, DNA and RNA, essentially propounded a view of individual selection, although he acknowledged, as Holldobler and Wilson note, that the altruistic behavior of the insect colony appeared to be an exception. Holldobler and Wilson join an emerging view that declares, "It's all of the above," and hence the nom "multilevel selection." The early advocates for multilevel selection, David Sloan Wilson and and Elliot Sober, refer to it as "a unified theory of natural selection that operates on a nested hierarchy of units." While declaring that "all selection is multilevel," Holldobler and Wilson acknowledge that the ultimate unit of evolution is the gene (or a group of alleles of interacting genes). Even Dawkins concedes, however, that the fate of a gene can be tied to the fate of other genes within the same phenotype, so the lines over the unit of natural selection have blurred as the debate ensues.
The unique case of the social insects posed a question for Darwin because he was bothered by the question of how the worker group of ants and other social insects could evolve if they were sterile and left no offspring. Holldobler and Wilson explain the principle of eusociality --- the care of offspring of a reproductive group by a worker group --- and the gem in this 500 page book is the presentation of a model, supported by some evidence, how the most advanced eusocial insects such as bees and leafcutter ants evolved their cohesive social organization of altruistic individuals over millions of years. While difficult for the lay person such as myself to follow on the first presentation, the theory is advanced by this sentence: "Altruism and eusociality are thus evidently born from the appearance of a phenotypically flexible eusocial allele (or ensemble of such alleles) in a progressive provisioning mother and between-group selection acting on emergent group traits, socially binding in nature and sufficiently powerful to overbalance the dissolutive effects of individual direct (within group) selection." Translation: at the gene selection level, traits are favored to enhance the survival of eggs or larvae by promoting social relationships that become strong enough (ie. that eliminate or minimize conflict within the group) to offset threats from competing social groups (other colonies or species) or the environment. This development was evolutionarily enabled because the alleles within the genes of the individual insects were flexible enough to activate this solution for survival. Finally, "when ecological and genetic factors advance a society to near the upper extreme of the superorganism continuum, subsequent selection may result in the complete loss of costly physiological structures involved in within-group competition" and "the capacity for 'selfishness' [becomes] insignificant because the underlying organs (for example, ovaries) important for within-group competition degenerate or become completely lost." For these unique groups of insects, the authors find that the colony is essentially an organism (phenotype), which they call a "superorganism." Borrowing a term from Dawkins, the authors conclude that the eusocial insect colony effectively becomes a target of natural selection because it is a coherent 'extended phenotype' of genes within colony members.
Importantly, the eusocial insects who form "superorganisms" are a very tiny percentage of the entire landscape of all species. They comprise only 15 species of more than 2600 species of insects. There is one species of vertebrates --- naked mole rats --- who fit this classification. However powerful the evidence for the superorganism is and the multilevel selection model, the truth remains that the critical unit of evolution is the gene. As the fictional character quoted in Richard Powers' Generosity says (see November 30 post), "Genes don't code for traits." Genes do code for chemical stimuli and sensory organs. This is not lost on Holldobler and Wilson who write, "Decision by decision, the insect responds to those stimuli to which its sensory and nervous systems are programmed to respond. These stimuli compose the highly filtered sensory world of the caste to which it belongs." And the science of evolutionary development, which posits that genes may not be expressed until a later developmental stage of life, undoubtedly has a role in explaining how insects "learn" altruistic behavior. Holldobler and Wilson provide evidence for this model as well in explaining that there are some species of female worker ants with ovaries in the nest that are simply suppressed by specific chemical recognition that a fertile egg-laying queen is in the nest, and when the queen dies, a worker ant's reproductive capabilities can be reactivated for the survival of the group.
If the reader of this book is, like me, learning about the social insects for the first time, there is a sense of awe in just how much we know about ants, bees, wasps, and termites. The quantum of information provided by the authors in support of their model, particularly about the ants, can be overwhelming at time. The authors' discussion of genetic social evolution and sociogenesis is delivered early in chapters 2 and 3, and the evidence follows for seven more chapters over 430 pages. After reaching the end of the book, go back and read chapters 2 and 3 again and the enormous amount of detailed evidence will come together.
Holldobler and Wilson's The Superorganism does not specifically address the big three areas of human inquiry -- the very large, the very small, and the human mind -- that I described in the August 31st post, but the book is devoted to that other question I mentioned: what is life? The subject-matter of The Superorganism is not entirely divorced from the books in the preceding posts. One of the links between each of the books reviewed in earlier posts is the subject of information and communication. The largest chapter of this beautiful book exhaustively summarizes what we know about communication within the species of the social insects --- not at the level of electrons and quarks and bosons that Seth Lloyd focused on --- but at the level of chemical compounds and the sensory capabilities of these insects: pheromones secreted to lay a trail for colony ants to follow leaders from the nest to food sources and back; odors of hydrocarbons that confirm the queen is present in the colony that shut down the reproductive capabilities of female workers so that only the queen becomes the source of eggs; odors of hydrocarbons that enable ants to distinguish members of their own colony from outsiders. There is also the suggestion, not inconsistent with Christine Keneally's statement in The First Word that human language is believed to have emerged from human motor skills, that insect communication may have emerged from the insect's motor skills.
But information is not the big idea in Superorganism. Information and communication among individual insects and competing groups of insects is just a significant piece of the evidence that supports the big idea in this book: multilevel natural selection. Since Richard Dawkins originally published The Selfish Gene in 1976, a debate has raged whether natural selection operates on genes, as advanced by Dawkins, or whether it operates on the individual organism (phenotype) --- the carrier of a collection of genes, or whether it operates on groups such as related kin, or more broadly communities or colonies. The advocates for each view were said to promote gene selection, individual selection, kin selection, or group selection respectively. Charles Darwin, because he lacked an understanding of Mendellian genetics, DNA and RNA, essentially propounded a view of individual selection, although he acknowledged, as Holldobler and Wilson note, that the altruistic behavior of the insect colony appeared to be an exception. Holldobler and Wilson join an emerging view that declares, "It's all of the above," and hence the nom "multilevel selection." The early advocates for multilevel selection, David Sloan Wilson and and Elliot Sober, refer to it as "a unified theory of natural selection that operates on a nested hierarchy of units." While declaring that "all selection is multilevel," Holldobler and Wilson acknowledge that the ultimate unit of evolution is the gene (or a group of alleles of interacting genes). Even Dawkins concedes, however, that the fate of a gene can be tied to the fate of other genes within the same phenotype, so the lines over the unit of natural selection have blurred as the debate ensues.
The unique case of the social insects posed a question for Darwin because he was bothered by the question of how the worker group of ants and other social insects could evolve if they were sterile and left no offspring. Holldobler and Wilson explain the principle of eusociality --- the care of offspring of a reproductive group by a worker group --- and the gem in this 500 page book is the presentation of a model, supported by some evidence, how the most advanced eusocial insects such as bees and leafcutter ants evolved their cohesive social organization of altruistic individuals over millions of years. While difficult for the lay person such as myself to follow on the first presentation, the theory is advanced by this sentence: "Altruism and eusociality are thus evidently born from the appearance of a phenotypically flexible eusocial allele (or ensemble of such alleles) in a progressive provisioning mother and between-group selection acting on emergent group traits, socially binding in nature and sufficiently powerful to overbalance the dissolutive effects of individual direct (within group) selection." Translation: at the gene selection level, traits are favored to enhance the survival of eggs or larvae by promoting social relationships that become strong enough (ie. that eliminate or minimize conflict within the group) to offset threats from competing social groups (other colonies or species) or the environment. This development was evolutionarily enabled because the alleles within the genes of the individual insects were flexible enough to activate this solution for survival. Finally, "when ecological and genetic factors advance a society to near the upper extreme of the superorganism continuum, subsequent selection may result in the complete loss of costly physiological structures involved in within-group competition" and "the capacity for 'selfishness' [becomes] insignificant because the underlying organs (for example, ovaries) important for within-group competition degenerate or become completely lost." For these unique groups of insects, the authors find that the colony is essentially an organism (phenotype), which they call a "superorganism." Borrowing a term from Dawkins, the authors conclude that the eusocial insect colony effectively becomes a target of natural selection because it is a coherent 'extended phenotype' of genes within colony members.
Importantly, the eusocial insects who form "superorganisms" are a very tiny percentage of the entire landscape of all species. They comprise only 15 species of more than 2600 species of insects. There is one species of vertebrates --- naked mole rats --- who fit this classification. However powerful the evidence for the superorganism is and the multilevel selection model, the truth remains that the critical unit of evolution is the gene. As the fictional character quoted in Richard Powers' Generosity says (see November 30 post), "Genes don't code for traits." Genes do code for chemical stimuli and sensory organs. This is not lost on Holldobler and Wilson who write, "Decision by decision, the insect responds to those stimuli to which its sensory and nervous systems are programmed to respond. These stimuli compose the highly filtered sensory world of the caste to which it belongs." And the science of evolutionary development, which posits that genes may not be expressed until a later developmental stage of life, undoubtedly has a role in explaining how insects "learn" altruistic behavior. Holldobler and Wilson provide evidence for this model as well in explaining that there are some species of female worker ants with ovaries in the nest that are simply suppressed by specific chemical recognition that a fertile egg-laying queen is in the nest, and when the queen dies, a worker ant's reproductive capabilities can be reactivated for the survival of the group.
If the reader of this book is, like me, learning about the social insects for the first time, there is a sense of awe in just how much we know about ants, bees, wasps, and termites. The quantum of information provided by the authors in support of their model, particularly about the ants, can be overwhelming at time. The authors' discussion of genetic social evolution and sociogenesis is delivered early in chapters 2 and 3, and the evidence follows for seven more chapters over 430 pages. After reaching the end of the book, go back and read chapters 2 and 3 again and the enormous amount of detailed evidence will come together.
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