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 evolution. Show all posts
Showing posts with label evolution. Show all posts
Wednesday, September 25, 2013
Thursday, March 14, 2013
Edward Humes, Monkey Girl: Evolution, Education, Religion and the Battle for America's Soul (2008)
Deception and religion have been joined at the hip for a very long time, perhaps as long as religion has existed in human culture given that religion has its origins in believing what we can never see or know. Monkey Girl is Edward Humes' account of the Dover Township, Pennsylvania school board's effort to introduce the subject of intelligent design into the high school science curriculum and the litigation that ensued when parents stepped forward and asked a court to enjoin the school board's effort on the ground that it offended the First Amendment of the U.S. Constitution. What the 6-week trial in a United States District Court exposed was concerted deceit on the part of groups opposed to the teaching of natural selection and what Charles Darwin called "descent with modification" in public school curriculum because it offended the biblical stories that lead them to the belief that god (an intelligent designer) created each of the species separately and the view of some that these acts of creation began no more than 10,000 years ago. Comparable acts of deceit in the commercial world would be called mislabeling or misbranding or fraud. In court, it is called perjury.
The drive to engage in the acts of deceit documented by Humes begins with the United States Supreme Court's decision in 1987 that the teaching of creationism offended the First Amendment's Establishment Clause and could not be taught in public schools. If creationism could not be mandated as a subject of instruction in United States public schools these groups began to think about branding creationism as something else, something that sounded like it belonged in the science classroom --- intelligent design. Their legal strategy, for example, compelled them to abandon the words "god" and "creator" and relabel god an "intelligent designer." Their legal strategy also compelled them to create a controversy when, at least in the scientific community, no substantial controversy existed: the existence of an intelligent designer would be deemed a serious scientific question and one that demanded that schools "teach the controversy." The lingo of creationism and its relationship to the book of Genesis had to be purged if science students had any chance of being taught an alternate explanation of the creation of species alongside natural selection and descent with modification in the classroom. This was no easy task. To biblical literalists, it was confusing and did not sit well with the hard core biblical believers who wanted to drive natural selection and "Darwinism" from science class because, in their view, it was atheistic. But for the advocates of intelligence design, their difficulties extended beyond the religious motivations of the Dover school board. Not only were the intelligent design advocates ultimately unable to succeed in concealing the religious motivations of the school board, it turns out there was a long and unambiguous record demonstrating that intelligent design had its intellectual seed in creationism. The very book that the intelligent design advocates wanted the high school students of Dover to have in their classroom, Of Pandas and People, had been drafted prior to the Supreme Court's 1987 decision in Edwards v. Aguillard, and the drafts had used the word creationism. By the time of publication, after the Supreme Court rendered its decision in Edwards, the word creationism had been deleted everywhere and replaced with the term intelligent design.
At the heart of the lawsuit, known as Kitzmiller v. Town of Dover, was this question: was intelligent design science or religion? For the plaintiffs, intelligent design was on trial; for the defendants and their supporters, traditional science was on trial. After a six week trial in which the court heard from scientists on both side of the question, the court found that intelligent design was not science; it was religion.
The scheme to inject intelligent design --- as opposed to creationism --- into the science curriculum begins with a paper developed by a University of California law professor, Phillip Johnson, that came to be known as the "wedge strategy," because it envisioned hammering a "wedge" into the tree of science by criticizing evolutionary theory --- putting science on the defensive and exploiting religious sentiment that was not only skeptical of evolutionary theory, but was essentially ignorant about natural selection and the body of scientific literature that had substantiated Darwin's natural selection model. The wedge document was developed by Johnson in collaboration with the Discovery Institute, and essentially outlines not a scientific research program, but a public relations strategy to persuade people that a scientific controversy existed and that the public needed to be made aware of the controversy. The wedge document was never intended to be made public, and it was forthright and honest in expressing the goals behind the wedge strategy, leaving no doubt about its theistic underpinning:
A central part of the Discovery Institute's strategy was to change the ground rules of science so that it not only included the natural, material world, but also the supernatural ethereal world. The problem with this project is that it is nothing less than the merger of science and religion. According to the testimony of the plaintiff's expert at the Kitzmiller trial, "Science is the systematic attempt to provide natural explanations for natural phenomena." The exclusion of the supernatural from science was unavoidable. A scientific theory is testable, and is capable of being proven false. The supernatural is not testable. Judge Jones concluded, "Intelligent design is predicated on supernatural causation. . . . Creationism, intelligent design, and other claims of supernatural intervention in the origin of life or of species are not science because they are not testable by the methods of science. These claims subordinate observed data to statements based on authority, revelation, or religious belief."
Numerous posts in this blog raise issues that are relevant to the Kitzmiller case:
Teleology v teleonomy. (June 12, 2011, May 24, 2010 and March 24, 2010 post).
The human propensity for self-deception and deception. (February 4, 2012, August 28, 2011, and May 22, 2011 and May 12, 2010 post)
Anthropomorphism, anthropotheism, and anthropodenial. (March 20, 2012, June 12, 2011 and June 17, 2010 post).
Dualism and materialism. ( December 17, 2012, February 27, 2011 and September 27, 2009 post)
At its core, the intelligent design movement, as exposed in the wedge document, is about as un-American as any group can be. The long-run goal is for design theory to permeate not only religious, cultural, and moral life, but also "political life." This is so contrary to the First Amendment of the United States Constitution, one would think the design movement's adherents were really living in modern Iran or some other theocracy. Yet what Monkey Girl reveals is that the intelligent design movement has so little respect for the First Amendment, because they believe the government has abandoned religion by recognizing the freedom of atheists, skeptics (agnostics), and pantheists who imagine a universe governed by natural laws (see January 31, 2013 post) and they believe the government has abandoned its moorings as a "Christian nation." In contrast, Humes closes out Monkey Girl with a quotation from the 1796 Treaty of Tripoli, signed by founding father President John Adams:
"As the Government of the United States of America is not, in any sense, founded on the Christian religion, as it has in itself no character of enmity against the religion, or tranquility of Mussulmen; and, as the said States never entered into any war, or act of hostility, against any Mahometan nation, it is declared by the Parties, that no pretext arising from religious opinions, shall ever produce an interruption of the harmony existing between the two countries." (Emphasis added).
Nor should one forget the Jefferson Bible, in which founding father Thomas Jefferson, excised the text pertaining to miracles and other supernatural events.
I have a proposal that will surely bring the intelligent design movement and creationists running back for the protection of the First Amendment. Congress should pass a law that requires every religious school class to teach the following every Saturday or Sunday: "The Book of Genesis is a story. It was written and later edited by men who could not explain their origins or the origins of the physical universe including other life on earth and life and other material beyond the earth. It's a wonderful story and it even has meaning, but it is just a story. Our origins really did not happen they way, Adam and Eve were not real people, and the other stories that purport to be written history of the Hebrews are merely stories as well. There may be some little historical basis in some of these stories, but they have been gilded, edited, redacted, and revised to fit a collective memory long after the events described in Genesis purportedly took place. And by the way, children, did you not see that Genesis mentions nothing about the dinosaurs and other animals that lived on earth millions of years ago, whose bones we find in the ground today. Children, do you not wonder why Genesis does not mention dinosaurs and other animals who no longer exist? The answer is simple. The men who wrote the stories in Genesis did not know about these animals. They were not as knowledgeable as you are today." Once the law is passed, I am sure there will be a lawsuit. Maybe the ACLU will be the plaintiff.
In Edwards v. Aguillard, Associate Justice of the Supreme Court Antonin Scalia dissented from the majority's decision that struck down Louisiana's statute that called for the "balanced treatment" of "creation science" and "evolution science" in Louisiana schools. The 7 member majority of the Court authored by Justice Brennan and the concurring opinions of Justice Powell and Justice White found plenty of evidence that creation science lacked a secular purpose and was religiously inspired. "This is not a hard case," wrote Justice White. The case came before the Supreme Court based on the trial court's grant of a motion for summary judgment, which meant the trial court found enough undisputed evidence presented by the plaintiff's challenging the Louisiana statute to warrant granting a judgment without a full evidentiary trial. Justice Scalia professed to take no position on the merits of "creation science," but he felt that Louisiana deserved a full evidentiary trial before an appellate court such as the US Supreme Court decided whether or not there was a valid secular purpose. One would think, and hope, that Justice Scalia, informed by the full evidentiary record in Kitzmiller, would have recognized as Justice White did in Edwards that "this is not a hard case" had the Kitzmiller case made its way to the Supreme Court for judicial review, and that he would recognize that intelligent design deserved the same fate that creation science received in Edwards.
The drive to engage in the acts of deceit documented by Humes begins with the United States Supreme Court's decision in 1987 that the teaching of creationism offended the First Amendment's Establishment Clause and could not be taught in public schools. If creationism could not be mandated as a subject of instruction in United States public schools these groups began to think about branding creationism as something else, something that sounded like it belonged in the science classroom --- intelligent design. Their legal strategy, for example, compelled them to abandon the words "god" and "creator" and relabel god an "intelligent designer." Their legal strategy also compelled them to create a controversy when, at least in the scientific community, no substantial controversy existed: the existence of an intelligent designer would be deemed a serious scientific question and one that demanded that schools "teach the controversy." The lingo of creationism and its relationship to the book of Genesis had to be purged if science students had any chance of being taught an alternate explanation of the creation of species alongside natural selection and descent with modification in the classroom. This was no easy task. To biblical literalists, it was confusing and did not sit well with the hard core biblical believers who wanted to drive natural selection and "Darwinism" from science class because, in their view, it was atheistic. But for the advocates of intelligence design, their difficulties extended beyond the religious motivations of the Dover school board. Not only were the intelligent design advocates ultimately unable to succeed in concealing the religious motivations of the school board, it turns out there was a long and unambiguous record demonstrating that intelligent design had its intellectual seed in creationism. The very book that the intelligent design advocates wanted the high school students of Dover to have in their classroom, Of Pandas and People, had been drafted prior to the Supreme Court's 1987 decision in Edwards v. Aguillard, and the drafts had used the word creationism. By the time of publication, after the Supreme Court rendered its decision in Edwards, the word creationism had been deleted everywhere and replaced with the term intelligent design.
At the heart of the lawsuit, known as Kitzmiller v. Town of Dover, was this question: was intelligent design science or religion? For the plaintiffs, intelligent design was on trial; for the defendants and their supporters, traditional science was on trial. After a six week trial in which the court heard from scientists on both side of the question, the court found that intelligent design was not science; it was religion.
The scheme to inject intelligent design --- as opposed to creationism --- into the science curriculum begins with a paper developed by a University of California law professor, Phillip Johnson, that came to be known as the "wedge strategy," because it envisioned hammering a "wedge" into the tree of science by criticizing evolutionary theory --- putting science on the defensive and exploiting religious sentiment that was not only skeptical of evolutionary theory, but was essentially ignorant about natural selection and the body of scientific literature that had substantiated Darwin's natural selection model. The wedge document was developed by Johnson in collaboration with the Discovery Institute, and essentially outlines not a scientific research program, but a public relations strategy to persuade people that a scientific controversy existed and that the public needed to be made aware of the controversy. The wedge document was never intended to be made public, and it was forthright and honest in expressing the goals behind the wedge strategy, leaving no doubt about its theistic underpinning:
- "to defeat scientific materialism and its destructive moral, cultural and political legacies.
- "to replace materialistic explanations with the theistic understanding that nature and human beings were created by God."
- to initially see, within five years, "intelligent design theory as an accepted alternative in the sciences and scientific research being done from the perspective of design theory" and within 20 years to see intelligent design theory as the dominant perspective in science" and to see "design theory permeate our religious, cultural, moral and political life."
- "Design theory promises to reverse the stifling dominance of the materialist worldview, and to replace it with a science consonant with Christian and theistic convictions."
A central part of the Discovery Institute's strategy was to change the ground rules of science so that it not only included the natural, material world, but also the supernatural ethereal world. The problem with this project is that it is nothing less than the merger of science and religion. According to the testimony of the plaintiff's expert at the Kitzmiller trial, "Science is the systematic attempt to provide natural explanations for natural phenomena." The exclusion of the supernatural from science was unavoidable. A scientific theory is testable, and is capable of being proven false. The supernatural is not testable. Judge Jones concluded, "Intelligent design is predicated on supernatural causation. . . . Creationism, intelligent design, and other claims of supernatural intervention in the origin of life or of species are not science because they are not testable by the methods of science. These claims subordinate observed data to statements based on authority, revelation, or religious belief."
Numerous posts in this blog raise issues that are relevant to the Kitzmiller case:
Teleology v teleonomy. (June 12, 2011, May 24, 2010 and March 24, 2010 post).
The human propensity for self-deception and deception. (February 4, 2012, August 28, 2011, and May 22, 2011 and May 12, 2010 post)
Anthropomorphism, anthropotheism, and anthropodenial. (March 20, 2012, June 12, 2011 and June 17, 2010 post).
Dualism and materialism. ( December 17, 2012, February 27, 2011 and September 27, 2009 post)
At its core, the intelligent design movement, as exposed in the wedge document, is about as un-American as any group can be. The long-run goal is for design theory to permeate not only religious, cultural, and moral life, but also "political life." This is so contrary to the First Amendment of the United States Constitution, one would think the design movement's adherents were really living in modern Iran or some other theocracy. Yet what Monkey Girl reveals is that the intelligent design movement has so little respect for the First Amendment, because they believe the government has abandoned religion by recognizing the freedom of atheists, skeptics (agnostics), and pantheists who imagine a universe governed by natural laws (see January 31, 2013 post) and they believe the government has abandoned its moorings as a "Christian nation." In contrast, Humes closes out Monkey Girl with a quotation from the 1796 Treaty of Tripoli, signed by founding father President John Adams:
"As the Government of the United States of America is not, in any sense, founded on the Christian religion, as it has in itself no character of enmity against the religion, or tranquility of Mussulmen; and, as the said States never entered into any war, or act of hostility, against any Mahometan nation, it is declared by the Parties, that no pretext arising from religious opinions, shall ever produce an interruption of the harmony existing between the two countries." (Emphasis added).
Nor should one forget the Jefferson Bible, in which founding father Thomas Jefferson, excised the text pertaining to miracles and other supernatural events.
I have a proposal that will surely bring the intelligent design movement and creationists running back for the protection of the First Amendment. Congress should pass a law that requires every religious school class to teach the following every Saturday or Sunday: "The Book of Genesis is a story. It was written and later edited by men who could not explain their origins or the origins of the physical universe including other life on earth and life and other material beyond the earth. It's a wonderful story and it even has meaning, but it is just a story. Our origins really did not happen they way, Adam and Eve were not real people, and the other stories that purport to be written history of the Hebrews are merely stories as well. There may be some little historical basis in some of these stories, but they have been gilded, edited, redacted, and revised to fit a collective memory long after the events described in Genesis purportedly took place. And by the way, children, did you not see that Genesis mentions nothing about the dinosaurs and other animals that lived on earth millions of years ago, whose bones we find in the ground today. Children, do you not wonder why Genesis does not mention dinosaurs and other animals who no longer exist? The answer is simple. The men who wrote the stories in Genesis did not know about these animals. They were not as knowledgeable as you are today." Once the law is passed, I am sure there will be a lawsuit. Maybe the ACLU will be the plaintiff.
In Edwards v. Aguillard, Associate Justice of the Supreme Court Antonin Scalia dissented from the majority's decision that struck down Louisiana's statute that called for the "balanced treatment" of "creation science" and "evolution science" in Louisiana schools. The 7 member majority of the Court authored by Justice Brennan and the concurring opinions of Justice Powell and Justice White found plenty of evidence that creation science lacked a secular purpose and was religiously inspired. "This is not a hard case," wrote Justice White. The case came before the Supreme Court based on the trial court's grant of a motion for summary judgment, which meant the trial court found enough undisputed evidence presented by the plaintiff's challenging the Louisiana statute to warrant granting a judgment without a full evidentiary trial. Justice Scalia professed to take no position on the merits of "creation science," but he felt that Louisiana deserved a full evidentiary trial before an appellate court such as the US Supreme Court decided whether or not there was a valid secular purpose. One would think, and hope, that Justice Scalia, informed by the full evidentiary record in Kitzmiller, would have recognized as Justice White did in Edwards that "this is not a hard case" had the Kitzmiller case made its way to the Supreme Court for judicial review, and that he would recognize that intelligent design deserved the same fate that creation science received in Edwards.
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.
Tuesday, December 14, 2010
Sean B. Carroll, The Making of the Fittest (2006)
This is a wonderful book to read following Genome (November 27, 2010 post). It tells another set of stories derived from sets of three-letter words utilizing combinations of the letters of A, C, G, and T. Published just seven years after the publication of Genome, and written just as the human genome was in its final stages of being decoded, The Making of the Fittest reveals just how much more we have learned about our DNA in such a short period of time.
Sean Carroll is the author of another book, previously published, Endless Forms Most Beautiful, which documented the genetic source of both embryonic development as well as physical development outside the embryo after birth. I cited this book in the previous post.
The key words in this volume are chance, selection, and time. As someone who was intrigued and stimulated by French biologist Jacques Monod's book, Chance and Necessity, almost 40 years ago, these three words, and Carroll's interpretation of them in the context of what we now know about DNA and evolution, reaffirm what I have long-believed about randomness and causality: that events in the universe (biological, chemical, and physical) are both random and determined and there is no flawed incongruity in saying so. While randomness may appear to be a function of limited foresight --- cognitive uncertainty and unpredictability, as Ridley suggests in Genome, randomness is neither predestined or (intelligently) designed. Yet hindsight informs us that these same events are part of a causal sequence, many of which are quite orderly and repeatable.
Prior posts on this blog reveal that I am a skeptic of the intelligent designer thesis. (See May 24, 2010 and May 12, 2010 posts). The Making of the Fittest is probably the most devastating condemnation of intelligent design ever published. One cannot read and understand this book without coming to the conclusion that it is simply impossible for any type of intelligence to program life and contemplate mutation and evolution in the manner that it actually occurs. While those in the intelligent design community believe that it is impossible to contemplate the complexity and variability in life without an intelligent designer (a code for God), Carroll demonstrates that it is impossible to contemplate the complexity and variability in life as the output of a design. Theists will condemn this statement as the view of someone who believes that life has no purpose: but theists misunderstand and confuse purpose, which is a psychological event, with random mutation, which is a biological and informational event.
Both Carroll, Ridley and many others have reported that there is a universal common ancestor of all species dating back to billions of year ago, and the species alive today all share common DNA and RNA in their respective genomes that has been copied, translated, inherited, and preserved over the eons. What makes species differ is variety in the genome, and "[t]he source of all variety is mutation." Carroll notes that mutation has several connotations that have led to false impressions about mutation: first, that all mutation is bad and is not creative, and second, that if mutations are random (which he says they are), then a random process cannot account for all the complexity we find in living things today. "This misconception is based upon a failure to distinguish between mutation and selection. The mutational process is blind, natural selection is not. Mutation generates random variation, selection sorts out the winners and losers. Furthermore, natural selection acts cumulatively," says Carroll.
And there are a variety of mutations of the genetic code. The most common is the equivalent of a typographical error in the process of copying the genetic code --- a substitution of one of the four letters for another. But there are also mutations involving deletions of code and insertions of repeating code or duplications. Sometimes these mutations actually mean something --- changing something about the phenotype in which the genetic code resides, but many, many times these changes mean nothing --- they don't change a thing about how the gene works. Some genes simply lose their meaning over time because they are no longer used, and these are called fossil genes. And some mutations that do have meaning simply do not survive to live another generation because selection is neither accomodating nor forgiving. When mutations occur repeatedly and have meaning --- in the sense that it changes something about the phenotype in which it resides --- and selection favors the survival of that mutation, then given enough time (many generations, thousands of years) we can find new species evolving. Carroll has reduced his mantra of chance, selection and time to this expression: "i) given sufficient time, ii) identical or equivalent mutations will arise repeatedly by chance, and iii) their fate (preservation or elimination) will be determined by the conditions of selection upon the traits they affect."
The Making of the Fittest illustrates this proposition through several well-documented examples, but the star in this story are the genes that code for proteins that develop opsins found in photoreceptors in the eye. Opsins are involved in vision and in converting a photon of light into an electrochemical signal that is transmitted along neural pathways --- in humans to the areas of the brain responsible for vision. These genes and their predecessors are very old, and selection has operated on mutations of the genetic code that develop opsins to cause different species to have varying levels of visual acuity, color recognition, and other funcitonal properties.
Life can be described in terms of both variation (complexity) as well as order -- by which I mean that there is repetition and some level of stasis. For some, it is unfathomable that complexity and order can exist absent some intelligent designer. But biological science, chemistry, and even physics establishes that variation and order in living things exist quite well without a designer. Monod's "necessity" is a matter of selection, and for very long periods of time external conditions --- natural environment, predators, and even a given specie's social environment --- are relatively static leading to little or no change that gives rise to the appearance of order. Much in the process by which genetic code is copied over and over again: there are few mistakes and faithful copies of genes are repeatedly made preserving the existing order of things. But beneath the surface of appearances, mutations occur, and these mistakes are not planned, they are not purposeful, and they are random.
Sean Carroll is the author of another book, previously published, Endless Forms Most Beautiful, which documented the genetic source of both embryonic development as well as physical development outside the embryo after birth. I cited this book in the previous post.
The key words in this volume are chance, selection, and time. As someone who was intrigued and stimulated by French biologist Jacques Monod's book, Chance and Necessity, almost 40 years ago, these three words, and Carroll's interpretation of them in the context of what we now know about DNA and evolution, reaffirm what I have long-believed about randomness and causality: that events in the universe (biological, chemical, and physical) are both random and determined and there is no flawed incongruity in saying so. While randomness may appear to be a function of limited foresight --- cognitive uncertainty and unpredictability, as Ridley suggests in Genome, randomness is neither predestined or (intelligently) designed. Yet hindsight informs us that these same events are part of a causal sequence, many of which are quite orderly and repeatable.
Prior posts on this blog reveal that I am a skeptic of the intelligent designer thesis. (See May 24, 2010 and May 12, 2010 posts). The Making of the Fittest is probably the most devastating condemnation of intelligent design ever published. One cannot read and understand this book without coming to the conclusion that it is simply impossible for any type of intelligence to program life and contemplate mutation and evolution in the manner that it actually occurs. While those in the intelligent design community believe that it is impossible to contemplate the complexity and variability in life without an intelligent designer (a code for God), Carroll demonstrates that it is impossible to contemplate the complexity and variability in life as the output of a design. Theists will condemn this statement as the view of someone who believes that life has no purpose: but theists misunderstand and confuse purpose, which is a psychological event, with random mutation, which is a biological and informational event.
Both Carroll, Ridley and many others have reported that there is a universal common ancestor of all species dating back to billions of year ago, and the species alive today all share common DNA and RNA in their respective genomes that has been copied, translated, inherited, and preserved over the eons. What makes species differ is variety in the genome, and "[t]he source of all variety is mutation." Carroll notes that mutation has several connotations that have led to false impressions about mutation: first, that all mutation is bad and is not creative, and second, that if mutations are random (which he says they are), then a random process cannot account for all the complexity we find in living things today. "This misconception is based upon a failure to distinguish between mutation and selection. The mutational process is blind, natural selection is not. Mutation generates random variation, selection sorts out the winners and losers. Furthermore, natural selection acts cumulatively," says Carroll.
And there are a variety of mutations of the genetic code. The most common is the equivalent of a typographical error in the process of copying the genetic code --- a substitution of one of the four letters for another. But there are also mutations involving deletions of code and insertions of repeating code or duplications. Sometimes these mutations actually mean something --- changing something about the phenotype in which the genetic code resides, but many, many times these changes mean nothing --- they don't change a thing about how the gene works. Some genes simply lose their meaning over time because they are no longer used, and these are called fossil genes. And some mutations that do have meaning simply do not survive to live another generation because selection is neither accomodating nor forgiving. When mutations occur repeatedly and have meaning --- in the sense that it changes something about the phenotype in which it resides --- and selection favors the survival of that mutation, then given enough time (many generations, thousands of years) we can find new species evolving. Carroll has reduced his mantra of chance, selection and time to this expression: "i) given sufficient time, ii) identical or equivalent mutations will arise repeatedly by chance, and iii) their fate (preservation or elimination) will be determined by the conditions of selection upon the traits they affect."
The Making of the Fittest illustrates this proposition through several well-documented examples, but the star in this story are the genes that code for proteins that develop opsins found in photoreceptors in the eye. Opsins are involved in vision and in converting a photon of light into an electrochemical signal that is transmitted along neural pathways --- in humans to the areas of the brain responsible for vision. These genes and their predecessors are very old, and selection has operated on mutations of the genetic code that develop opsins to cause different species to have varying levels of visual acuity, color recognition, and other funcitonal properties.
Life can be described in terms of both variation (complexity) as well as order -- by which I mean that there is repetition and some level of stasis. For some, it is unfathomable that complexity and order can exist absent some intelligent designer. But biological science, chemistry, and even physics establishes that variation and order in living things exist quite well without a designer. Monod's "necessity" is a matter of selection, and for very long periods of time external conditions --- natural environment, predators, and even a given specie's social environment --- are relatively static leading to little or no change that gives rise to the appearance of order. Much in the process by which genetic code is copied over and over again: there are few mistakes and faithful copies of genes are repeatedly made preserving the existing order of things. But beneath the surface of appearances, mutations occur, and these mistakes are not planned, they are not purposeful, and they are random.
Sunday, September 27, 2009
Michael Gazzaniga, Human (2008)
In the September 18th post, I concluded that a grander treatment of the subject of mirror neurons should be forthcoming someday, a volume that more completely integrates the role of mirror neurons with the biological operations of the mind and body and discusses consciousness memory, and evolution. I did not expect that such a book was already on The Bookshelf and was the next book to come off the shelf. Human, by U.C. Santa Barbara neuroscientist and psychology professor, Michael Gazzaniga , is such a book. While not specifically about mirror neurons, this larger look at the landscape of language, memory, emotion, perception, primate evolution and behavior, infant behavior and development of the human brain gives due recognition to discovery and role of mirror neurons.
In the Mystery of Consciousness, University of California philosophy professor, John Searle, writes, "The mystery of consciousness will gradually be removed when we solve the biological problem of consciousness." That's a remarkable statement from the philosophical community, where for millenia its leading lights have been debating and struggling with non-biological metaphysical ideas about what form reality takes and how we know reality. For Searle, who rejects the mind-body dualism of Descartes, "The 'problem of consciousness' is the problem of explaining exactly how the neurobiological processes in the brain cause our subjective states of awareness or sentience. . . the problem of consciousness is a scientific research project like any other." And that is a task that Gazzaniga embarks upon in Human.
While Searle appears ready to jettison philosophy of the mind for the biology of the mind, it is my belief that understanding the human mind is primarily biology and chemistry and physics (neuronal activity after all is electro-chemical), but it is also empirical anthropology, paleontology, research about other species, sociology, and psychology too. The human brain is the most important feature that distinguishes humans from other species. Gazzaniga would agree, and Human is engaging on all disciplines. There is a growing body of research that recognizes this interdisciplinary approach including Pascal Boyer's Religion Explained , Paul Bloom's Descartes' Baby , Steven Rose's The Future of the Brain , and Marc Hauser's Moral Minds. Each of these books explores one or more of the aspects of Gazzaniga's inquiry: what is unique about being human? which explores the answer inside the human mind.
Philosopher Searle and neuroscientist Antonio Damassio reject Cartesian dualism, but neuroscientist Gazzaniga says: we all act like dualists. "We are animate objects, which are the subject to the physical laws of animate objects, but we also have nonperceptual psychological properties not subject to physical laws." It is the latter that is one of the unique of attributes of being human: "we are the only animals that reason about unobservable forces ... we alone ... try to explain an effect as having been caused by something." That we may "act like" there is an unseen world separate from the physical world does not axiomatically lead to the conclusion that there is a dual world of the mental forms separate from a physical world of the senses. Pascal Boyer has provided one cogent explanation why the human mind is uniquely willing to recognize unseen agents, but he does not conclude that our psychological properties are not subject to physical laws. In the end, Gazzaniga does not appear to disagree. Gazzaniga is well-known for his split-brain research of patients suffering from severe epilepsy and the only treatment is to sever the corpus collosum that connects the right side of the brain from the left side. The right side of the brain is not a problem solver; it is good at perceiving, attentional skills, and emotions, but it is the cognitive left side of the brain that takes all the input coming into the brain and makes sense of it. The left side of the brain, says Gazzaniga, is the "interpreter" of our conscious experience, and in the course of acting as an "interpreter" this biological organ organizes information in a way to create a self-conscious self (an image of ourselves in our mind, separate from our physical self, or as Antonio Damassio calls it, our "movie within a movie"), another unique attribute of what makes us human. But this is the outcome of biological processes, not a feature of a separate world of the mind.
Enough of dualism or not! There are important nuggets of information in Human. The human brain is unique, not merely because of its size relative to our body weight or size, but because the way it is organized into modules and its connectivity. We learn of two genes that are regulators of brain size: microencephalin and ASPM. There is evidence of accelerated evolution of microencephalin in primates, and a variant of microencephalin appeared about 37,000 years ago about the same time that corresponds with culturally modern humans. A variant of ASPM appeared in humans about 5800 years ago, which coincides with the establishment of cities, agriculture, and written language. We don't know whether these genetic developments are in fact linked with cultural development and language, but it is certainly suggestive.
At the end of the book, we meet Merlin Donald who developed what is called mimesis theory: that the ability to imitate motor action is the foundation of language, human consciousness, and human culture. Language and gesture, the subject of the August 31 post on Christine Kennealy's The First Word, requires fine motor skills, which must be flexible enough to involve a voluntary control of muscles to mimic or rehearse an action undertaken by some other animate object, observe its consequences, store it in memory, and then change what must be changed. Donald calls this a "rehearsal loop," which he says is uniquely human. This requires feedback loops in the brain --- part of the brain's connectivity --- whereby the brain's ability to perceive (the right side) is connected the brain's cognitive capacity (in the left side) to connect to the action, and in order for the brain to imitate another animate object (such as another human), the brain must be self-aware. Is it this connectivity that is tied to the genetic developments in humans thousands of years ago?
Finally, we meet Jeff Hawkins, a creator of the Palm Pilot, who has co-authored a book called On Intelligence. Hawkins rejects the idea that the human brain is "computational." The brain does not compute the answers to problems; the neocortex is a memory system, which differs from a computer. The brain uses stored memory from past experience to make predictions -- which Hawkins asserts is the primary function of the neocortex and the foundation of human intelligence. Recall from the September 18 post on Marco Iacoboni's Mirroring People, that the part of the brain where mirror neurons are found is a part of the neocortex, which is responsible for planning and execution. The neocortex is the center or our attentive capacity, and we come to attention when we fail to accurately predict something. So it is here that motor coordination, drawing on memory, planning and execution all occur, with help from other, evolutionarily older parts of the brain tied to the senses. This is a key part of the brain responsible for attention and self-awareness, forming what Damassio characterizes as our "extended consciousness." Hawkins' model of the brain depends on feedback loops where information must flow back and forth comparing what is happening to what is predicted to happen. Information about what is happening flows in one direction; information about what memory tells you is expected to happen flows in another direction. This is not how a computer operates, which relies heavily on parallel processes, and arguably it suggests that robots will never replace us.
I said in a previous post that one of the big three areas for human inquiry is the human mind. Human delineates why this is true. Mirror neurons, fine motor skills that enable us to imitate, connectivity among modules in the brain and feedback loops, extended consciousness, language, and self-awareness are some of the important attributes of what make humans unique. To comprehend how the human mind works is really the key to understanding what makes us unique in the animal kingdom. Not all of the answers are here, but there is a lot in one book to fathom this huge question.
In the Mystery of Consciousness, University of California philosophy professor, John Searle, writes, "The mystery of consciousness will gradually be removed when we solve the biological problem of consciousness." That's a remarkable statement from the philosophical community, where for millenia its leading lights have been debating and struggling with non-biological metaphysical ideas about what form reality takes and how we know reality. For Searle, who rejects the mind-body dualism of Descartes, "The 'problem of consciousness' is the problem of explaining exactly how the neurobiological processes in the brain cause our subjective states of awareness or sentience. . . the problem of consciousness is a scientific research project like any other." And that is a task that Gazzaniga embarks upon in Human.
While Searle appears ready to jettison philosophy of the mind for the biology of the mind, it is my belief that understanding the human mind is primarily biology and chemistry and physics (neuronal activity after all is electro-chemical), but it is also empirical anthropology, paleontology, research about other species, sociology, and psychology too. The human brain is the most important feature that distinguishes humans from other species. Gazzaniga would agree, and Human is engaging on all disciplines. There is a growing body of research that recognizes this interdisciplinary approach including Pascal Boyer's Religion Explained , Paul Bloom's Descartes' Baby , Steven Rose's The Future of the Brain , and Marc Hauser's Moral Minds. Each of these books explores one or more of the aspects of Gazzaniga's inquiry: what is unique about being human? which explores the answer inside the human mind.
Philosopher Searle and neuroscientist Antonio Damassio reject Cartesian dualism, but neuroscientist Gazzaniga says: we all act like dualists. "We are animate objects, which are the subject to the physical laws of animate objects, but we also have nonperceptual psychological properties not subject to physical laws." It is the latter that is one of the unique of attributes of being human: "we are the only animals that reason about unobservable forces ... we alone ... try to explain an effect as having been caused by something." That we may "act like" there is an unseen world separate from the physical world does not axiomatically lead to the conclusion that there is a dual world of the mental forms separate from a physical world of the senses. Pascal Boyer has provided one cogent explanation why the human mind is uniquely willing to recognize unseen agents, but he does not conclude that our psychological properties are not subject to physical laws. In the end, Gazzaniga does not appear to disagree. Gazzaniga is well-known for his split-brain research of patients suffering from severe epilepsy and the only treatment is to sever the corpus collosum that connects the right side of the brain from the left side. The right side of the brain is not a problem solver; it is good at perceiving, attentional skills, and emotions, but it is the cognitive left side of the brain that takes all the input coming into the brain and makes sense of it. The left side of the brain, says Gazzaniga, is the "interpreter" of our conscious experience, and in the course of acting as an "interpreter" this biological organ organizes information in a way to create a self-conscious self (an image of ourselves in our mind, separate from our physical self, or as Antonio Damassio calls it, our "movie within a movie"), another unique attribute of what makes us human. But this is the outcome of biological processes, not a feature of a separate world of the mind.
Enough of dualism or not! There are important nuggets of information in Human. The human brain is unique, not merely because of its size relative to our body weight or size, but because the way it is organized into modules and its connectivity. We learn of two genes that are regulators of brain size: microencephalin and ASPM. There is evidence of accelerated evolution of microencephalin in primates, and a variant of microencephalin appeared about 37,000 years ago about the same time that corresponds with culturally modern humans. A variant of ASPM appeared in humans about 5800 years ago, which coincides with the establishment of cities, agriculture, and written language. We don't know whether these genetic developments are in fact linked with cultural development and language, but it is certainly suggestive.
At the end of the book, we meet Merlin Donald who developed what is called mimesis theory: that the ability to imitate motor action is the foundation of language, human consciousness, and human culture. Language and gesture, the subject of the August 31 post on Christine Kennealy's The First Word, requires fine motor skills, which must be flexible enough to involve a voluntary control of muscles to mimic or rehearse an action undertaken by some other animate object, observe its consequences, store it in memory, and then change what must be changed. Donald calls this a "rehearsal loop," which he says is uniquely human. This requires feedback loops in the brain --- part of the brain's connectivity --- whereby the brain's ability to perceive (the right side) is connected the brain's cognitive capacity (in the left side) to connect to the action, and in order for the brain to imitate another animate object (such as another human), the brain must be self-aware. Is it this connectivity that is tied to the genetic developments in humans thousands of years ago?
Finally, we meet Jeff Hawkins, a creator of the Palm Pilot, who has co-authored a book called On Intelligence. Hawkins rejects the idea that the human brain is "computational." The brain does not compute the answers to problems; the neocortex is a memory system, which differs from a computer. The brain uses stored memory from past experience to make predictions -- which Hawkins asserts is the primary function of the neocortex and the foundation of human intelligence. Recall from the September 18 post on Marco Iacoboni's Mirroring People, that the part of the brain where mirror neurons are found is a part of the neocortex, which is responsible for planning and execution. The neocortex is the center or our attentive capacity, and we come to attention when we fail to accurately predict something. So it is here that motor coordination, drawing on memory, planning and execution all occur, with help from other, evolutionarily older parts of the brain tied to the senses. This is a key part of the brain responsible for attention and self-awareness, forming what Damassio characterizes as our "extended consciousness." Hawkins' model of the brain depends on feedback loops where information must flow back and forth comparing what is happening to what is predicted to happen. Information about what is happening flows in one direction; information about what memory tells you is expected to happen flows in another direction. This is not how a computer operates, which relies heavily on parallel processes, and arguably it suggests that robots will never replace us.
I said in a previous post that one of the big three areas for human inquiry is the human mind. Human delineates why this is true. Mirror neurons, fine motor skills that enable us to imitate, connectivity among modules in the brain and feedback loops, extended consciousness, language, and self-awareness are some of the important attributes of what make humans unique. To comprehend how the human mind works is really the key to understanding what makes us unique in the animal kingdom. Not all of the answers are here, but there is a lot in one book to fathom this huge question.
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