Monday, September 27, 2010
Charles Darwin penned On the Origin of Species during a time when the capitalist economic system was gaining great momentum. Certainly, his observation of human behavior in the capitalist economic system had an influence on the observations he made about plant and animal species while aboard the HMS Beagle. However, the reverse must also be true, as the theory of natural selection that Darwin developed throughout his academic career extends to the human species as well.
Throughout human history, man has made use of both the environment and technology to progress into some of the societies to which we now belong. The peoples of Western Europe advanced technology to the point where the English were able to colonize a host of countries during the age of imperialism. North America was part of this great colonization, where some of the world's greatest technological and medical advances have been made.
Past the age of hunter-gatherer tribes, technology has been the major driving force that has forged the evolution of man. There are still a number of hunter-gatherer societies throughout the world, such as the San Bushmen of the Kalahari desert or the Hewa people of New Guinea, who have had to resort to farming and traversing larger amounts of land in order to survive. Peoples such as the San Bushmen and the Hewa are disappearing rapidly, as have many other similar tribes, due to their inability to advance technologically at the rate at which the majority of the world's population has.
The development of farming allowed people to control their food sources and with the development of various technologies, has grown to the point where farming helps to support the entire world's population. However, developments in crop technologies such as altering the genetic makeup of certain strains of crops has also allowed man to grow stronger crops that are less susceptible to weather conditions and able to grow in less favorable conditions. In a world that can only support a limited population in a given land space, a majority of humans have evolved our methods of survival in the way of farming in order to support ourselves no matter the weather conditions.
In subsequent posts, I would like to address the idea of the strongest survive in relation to the human condition in further detail. Until then, stay strong!
Friday, September 24, 2010
1) LibriVox - complete 6th London edition - each chapter usually read by a different volunteer (some sounding like radio personalities, others rather difficult to understand)
2) Richard Dawkins reads Origin
An abridged reading of the original edition. Dawkins, an Oxford zoologist who along with Steven Jay Gould were leaders of the two main camps in the 'Darwin Wars' over evolutionary interpretation of natural selection, is particularly famous for his book The Selfish Gene. He also has a rich & pleasing reading voice (to my ear).
(very) brief review of audiobook
Darwin’s book The Origin of Species was the most controversial and most important scientific book in the history of science. It’s arguably the greatest idea ever published and shook the earth at its core with its ideas about descent with modification, and natural selection. Darwin used scientific reasoning to understand nature. He used the scientific principals of experimentation and observation and inductive reasoning to back his theories about natural selection and descent with modification.
The reason why the book turned out to be so controversial was that the logical extension of Darwin's theory was that us humans were simply another form of animal and not the divine creatures that we were told we were. His theories made it seem possible that humans might just have evolved from other animals just as the great apes did. These ideas were thought of as blasphemy in those times and Darwin was vehemently attacked, particularly by the Church.
It should be noted that Darwin did not specifically refer to man in the origin of species but used other animals to demonstrate his points. Nevertheless his ideas could be extended to humans and put into question the ideas of religion and creationism. Its fair to say that most atheist today consider Darwin’s theories to be the main argument against god and/or religion.
Darwin himself seemed to by confused by the problems that had arisen from theory and did not see it as a explicit denial of God/Religion. This is evident in a letter wrote in 1860 between Darwin Asa Gray “a devout Presbyterian” who looked at the connection between natural selection to natural theology and published many reviews on how they are compatible with each other.
“With respect to the theological view of the question; this is always painful to me.— I am bewildered.– I had no intention to write atheistically. But I own that I cannot see, as plainly as others do, & as I [should] wish to do, evidence of design & beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent & omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of caterpillars, or that a cat should play with mice. Not believing this, I see no necessity in the belief that the eye was expressly designed. On the other hand I cannot anyhow be contented to view this wonderful universe & especially the nature of man, & to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton.— Let each man hope & believe what he can.”
As suggested by Professor Ogden in lecture (9 Sept 2010), when looking for antagonists while reading Origin, one candidate is Lamarck.
Darwin takes multiple opportunities to diminish the ideas of Jean-Baptiste Lamarck ('inheritance of acquired characters' where actions lead to heritable physical changes - a common example given is an individual giraffe wanting to reach high leaves, so it stretches its neck, leading to longer necks in its offspring, and thereby to longer necks in the population over time).
Darwin also had similar ideas himself: namely, his theory of pangenesis. In Origin, Darwin refers to the disuse of organs leading to their reduction or absence in populations over time. He lists, for example, the loss of upright ears in domesticated animals and the loss of sight in cave-dwelling creatures.
On the basis of his experiments with domesticated species, Darwin wrote a two-volume treatise on domestication, published in 1868, in which, he developed a theory of heredity which he called 'pangenesis'.
In this theory Darwin postulated that each organ of the body gives off microscopic particles which he called 'gemmules' and that these gemmules are collected in the reproductive organs where they can influence the corresponding shape, size, and functions of the organs of the offspring. Darwin wanted to account for his belief that some characteristics or habits acquired during a parent's lifetime could affect the corresponding attributes of its offspring. This he usually called 'use-and-disuse heredity': the more familiar phrase is 'the inheritance of acquired characters' or 'Lamarckism', named after Jean Baptiste de Lamarck. However, Lamarck's theory was rather different in that he postulated a desire for change, or besoin, which caused that change to happen in the organism itself and then to be passed on to its offspring. In Darwin's time this aspect of Lamarck's theory was not generally accepted, but virtually every scientist believed that characters acquired by use or disuse could be inherited.
Darwin developed his theory of pangenesis in order to describe how use-and-disuse inheritance could occur. But he realized his theory was purely speculative and therefore put little faith in it. When it was soundly criticized by his cousin Francis Galton (himself an eminent psychologist, statistician and student of heredity), Darwin quietly dropped pangenesis, though he continued to accept the inheritance of acquired characters.
As evidence of Darwin's continuing influence, a 2009 article posted on the Institute of Science in Society site indicates that even 150 years later, researchers are still drawing connections to Darwin's pangenesis theory. The article details blood transfusions between different coloured birds, resulting in plumage colour changes over generations.
Interestingly, there is also ongoing research by Nishihara (Verification of Use and Disuse theory of Lamarck in Vertebrates Using Biomaterials) to test Lamarck's theory as well, as published in Biogenic Amines in 2003.
Taking a step sideways, the notion that genes are not the only carriers of human legacy is a popular one. In Richard Dawkins influential neo-Darwinian book The Selfish Gene , the last chapter of the original edition takes a radical departure from genetics and introduces the concept of memes as the mechanism of cultural transmission. "What, after all, is so special about genes?"
Defined as "a unit of cultural transmission, or a unit of imitation ... Examples of memes are tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches. Just as genes propagate themselves in the gene pool by leaping from body to body via sperms and eggs, so memes propagate themselves in the meme pool by leaping from brain to brain via a process which, in the broad sense, can be called imitation."
Dawkins suggests religion as a prime example of a meme:
Consider the idea of God ... Probably it originated many times by independent 'mutation' ... How does it replicate itself? By the spoken and written word, aided by great music and great art. Why does it have such a high survival value? ... its great psychological appeal. It provides a superficially plausible answer to deep and troubling questions about existence.
As shown by the recent article referring to Darwin's gemmules, and by Dawkin's extension of neo-Darwinian genetic theory to cultural transmission by memes, it is clear that Darwin's ideas continue to inspire research, discussion, and ideas. Far from being antiquated and outdated, Darwinism remains relevant and as this blog's title asserts: 'Darwin Kicks Butt'.
In her 2009 book, The Genial Gene, Stanford University researcher, Dr. Joan Roughgarden outlines her team's critique of Darwin's sexual selection outlined in The Descent of Man, and Selection in Relation to Sex (1871).
- Priscilla Long wrote a comprehensive review of The Genial Gene.
- Books Inc has long (over an hour) video of Dr. Roughgarden discussing her book.
- Her other books include:
- Evolution's Rainbow exploring gender & sexuality in nature
- Evolution and Christian Faith: Reflections of an Evolutionary Biologist finding harmony between the Bible and evolution. A podcast of Dr. Roughgarden as guest of the Forum at Grace Cathedral is available.
Darwin's idea of sexual selection (dramatized in class on 16 Sept 2010):
- Male ornaments (such as peacock's tail & deer's antlers) evolved because females preferred them.
- Males fight other males as females prefer the victors as mates.
- Males are 'passionate' whereas females are 'coy'. Males have lower reproductive costs than females.
- Females have a common (rather than individual) aesthetic ranking of males - all females would prefer the same type of male.
Roughgarden argues that sexual selection is wrong because
1) The sexual selection template offered by Darwin is violated by many species. Female selection exists, but its purpose is not to choose beautiful & well-armed males.
2) Many species previously thought to support Darwin's theory, do not, upon thorough investigation. For example, peahens (covered in lecture) were thought to prefer peacocks with big, fancy tails. Research now suggests that both sexes once had brightly coloured tails, but the ground-nesting females lost the bright plumage (shown to be inhibited by female hormones).
3) Contradictions exist between sexual-selection and population-genetic theories
Dr. Roughgarden's book also takes aim at neo-Darwinism (natural selection synthesized with genetics) as well. Her term: 'genial gene', responds to & aims to replace the concept of the 'selfish gene' (put forward by Richard Dawkins) with one including cooperation & teamwork. As Professor Ogden showed in lecture on September 8, Darwin's theory of natural selection is Whigism applied to evolution. Similarly, perhaps Dr. Roughgarden's cooperative theory reflects current political sensibilities applied to sexual selection.
Sexual & Social selection as applied to people...
Of direct relevance to the Humanities, Roughgarden specifies four topics related to human behaviour alone and compares sexual & social selection head-to-head:
- SeS (sexual selection): women attracted to men displaying traits representative of their genetic quality; men promiscuous.
- SoS (social selection): men & women choose each other equally based on factors promoting effective raising of children
- SeS: brain is secondary sexual character "the counterpoint of the peacock's tail, an ornament used by men to attract women ... females need big brains to appreciate the brains of men"
- SoS: brains needed to participate in social infrastructure & successfully raise children
- SeS: allows rejected men to reproduce, by force
- SoS: form of domination against males or females; not related to reproduction
4) Extra-Pair Paternity (women having children by men other than husband)
- SeS: women mating with men "genetically superior to their husbands, provided they can retain their husband's parental investment"
- SoS: "procuring a distributed commitment to protection, safety, and resource sharing through political alliance"
Propagation of errors in classic research on Darwin's Sexual Selection...
As an example of the need for scientific rigor when testing theories, even those put forward by scientific giants like Darwin,
(Also an example of genetic fallacy: 'mistaking an account of something's [i.e. a theory's] origin as an explanation of its truth or fallacy' [Dr. Stephen Ogden, lecture 23 Sept. 2010])
Roughgarden documents the results of various reappraisals of classic research by Bateman previously thought to decisively confirm sexual selection.
Roughgarden reports that one reappraisal group finds:
"subsequent 'dogmatization' of Bateman's findings. They observe that key researchers in the field... as well as textbook authors... present data only from the graph that is claimed to support sexual selection, while ignoring the other
... in some cases, Bateman's data and methodology was misrepresented and embellished when doing so strengthened preconceived notions of male and female behavior."
Another group made these statements about Bateman's research:
"his methods had flaws, including the elimination of genetic variance, sampling biases, miscalculations of fitness variances, statistical pseudo-replication, and selective representation of data."
"We conclude that Bateman's results are unreliable, his conclusions are questionable, and his observed variances are similar to those expected under random mating...[but we] do not intend this article as a criticism of Bateman"
"I admire the thoroughness of these reviewers and appreciate their circumspection. Still, I wonder whether the delicacy of phrase apparent in their conclusions serves the public's need to know the truth. These three critiques of Bateman and later workers have been devastating. There's simply no justification for continued adherence to the sexual-selection narrative on the basis of Bateman's work."
Caution urged in treating sexual selection as fact...
Roughgarden summarizes her view on the state of the sexual selection theory:
"The sexual selection narrative has been widely and uncritically adopted as axiomatic by these disciplines [psychology, anthropology, sociology, philosophy, ethics, and theology] as a scientific and true account of biological nature ... the sexual-selection area of evolutionary biology is not settled science, is in considerable flux, and is not ready for export. I hope, too, that journalists and science writers will withhold, or at least greatly qualify, their speculations and sound bites about the evolution of human social behavior."Response from an authority on sexual selection, Dr. Tim Clutton-Brock...
- parental care is not a direct consequence of gamete size
- sexual selection strength is not necessarily higher in males than females
- females may compete with other females (for parental-care resources) as strongly as males compete with other males for mates
He also comments on the general lack of clear knowledge about sexual selection:
"where females compete directly with each other, it is often unclear precisely what they are competing for. Where females have developed obvious secondary sexual characters, it is often uncertain whether these are used principally to attract males or in intrasexual competition for resources and how their development is limited is unknown. And, where males show consistent mating preferences for particular categories of females, we do not yet know whether they are selecting for heritable differences in female quality or for nonheritable variation in fecundity for for both"
However, in the final analysis, he insists:
"the theory of sexual selection still provides a robust framework that explains much of the variation in the development of secondary sexual characters in males, although ... [the whole topic is] more complex than was originally supposed. The recognition of these complexities helps to refine the assumptions and predictions of the theory of sexual selection but does not undermine its basic structure."
Darwin's attitude to criticism...
Darwin himself noted, upfront, the problems he saw with his theory of natural selection:
Long before the reader has arrived at this part of my work, a crowd of difficulties will have occurred to him. Some of them are so serious that to this day I can hardly reflect on them without being in some degree staggered (The Origin of Species, 6th ed. p.207)
In the sixth and final edition of The Origin of Species, he spends chapters specifically addressing objections to his theory. For example, Chapter Six is entitled: Difficulties of the Theory. Darwin did not shy away from criticism from colleagues, but rather faced it head on. Those researchers who unfortunately chose to promote Darwinism at the expense of good science could take a lesson from Darwin.In fact, the theory of sexual selection is an additional mechanism Darwin suggested to try to overcome a specific problem he saw with natural selection [Dr. Stephen Ogden, Hum 321 lecture 16 Sept. 2010]. Namely, the difficulty that some traits appear to be injurious to an individual, yet continue to be inherited - seeming to violate the principles of Natural Selection.
Darwin used Sexual Selection to explain this apparent contradiction, indicating that secondary sexual characters are useful in the struggle between males for possession of females [Dr. Stephen Ogden, Hum 321 lecture 16 Sept. 2010].
On the veracity of sexual selection, Darwin himself admits: "I am aware that much remains doubtful" (The Descent of Man, p608). Roughgarden's alternative theory of social selection includes a 26 point chart of direct comparison with sexual selection, directly engaging Darwin's theory, and showing the great weight that his theory has in current research. Supporting Darwin's general theory of natural selection, Roughgarden concludes in her final chapter of The Genial Gene:
the 200 years since Darwin's birthday have confirmed ... Darwin's hypothesis about descent and common ancestry. (p.235)
Darwin trusted in the scientific process, of which criticism, peer review, and reevaluation are a part:
ignorance more frequently begets confidence than does knowledge: it is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science. (The Descent of Man, p.2)
In the book Guns, Germs and Steel: The Fates of Human Societies, Jared Diamond chronicles how Europeans living in cities allows plagues to spread rapidly, with those surviving and reproducing being resistant or better able to recover. The result is a more resistant population. In contrast, when Europeans traveled to the new world, bringing germs with them, the native American populations, who had never been exposed to these particular diseases, were decimated, undergoing the same process as Europeans experienced earlier.
Similarly, in cultures where communal drinking containers were used (ie kava vessels in Fiji), many diseases were transmitted to the entire group, again resulting in a more resistant population over time.
One way that human populations differ from the other organic populations described by Darwin is the human use of drugs, vaccines, and sophisticated medical medical procedures to treat diseases, injuries, and medical conditions. These go beyond the genetic makeup of a person, and make the 'selection' process more complex.
For example, the rise in cesarean births allows babies with larger heads to be born and survive, when otherwise, the result would often be death of the baby, the mother, or both. This medical procedure allows infant head size to increase over time, perhaps with other results, such as increased brain size and any accompanying benefits (or disadvantages) that might produce.
In a disease context, the use of AIDS medications allows more people with AIDS - who would have otherwise have died, if they lacked natural resistance - to survive & reproduce.
Another difference in human populations is the use of clothing, buildings, and technology to survive changes in environment. While animal & plant populations are largely limited to natural genetic variation for members to survive changes in environment (or migration to areas with more favourable conditions), human populations are able to use technology to expand into new territories or to survive environmental changes. For example, human beings do not need to grow their own fur coat to survive life in the Antarctic, but can build & heat suitable home or research facilities & can wear synthetic coats (or wear the furs of other animals) to survive, changes that do not require genetic change in the population.
Thus, Darwin's principle of the strong surviving & the weak dying can be seen in action throughout history. However, in human populations, medical and other technologies allow the survival of individuals who would otherwise have died, if genetic variation within the population alone was responsible for survival.
Thursday, September 23, 2010
It may not be a logical deduction, but to my imagination it is far more satisfactory to look at such instincts as… ants making slaves… larvae… feeding within live bodies… not as specially endowed or created instincts, but as small consequences of one general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die. (p.219-20)
As someone who has read his book The Origin of Species this quote makes perfect sense. I do believe that nature has the upper hand when dealing out the cards of life, and a species may have very little say in whether they survive or die off. If a bird is born without the ability to fly, and is born on an island with little sustenance, how is it capable of surviving? It can try and survive on what little it has, but when it is not able to adapt to its environment it will not survive. This goes for an entire species born without the proper variations to compete against its environment and other species or species of the same genus. For those species that do survive, their variations will continue through generations, and be combined with other variations until nature deals out one that is badly adapted. This species will then struggle to survive, but die if its competitors get the better of him. To me, this is the long, slow process of natural selection.
Darwin’s use of the word “strength” can be interpreted and applied in various ways. In my mind, it is important to include intelligence as a form of strength. Many individuals may have the intellectual strength to overcome their “opponents” in the struggle for life through taking advantage of them, conning them or depending on them. In this way though, Darwin may also include “habit” as a form of intelligence, only an intelligence built in to a species subconscious. In all, Darwin’s theory that the “strongest live and the weakest die” rings true in the laws of nature.
Wednesday, September 22, 2010
I hope to bring you more details on the supporters of Darwin soon!
Tuesday, September 21, 2010
As a staunch supporter of Darwin I am not sure how to construct a posting that provides evidence of how extraordinarily amazing he actually is in a succinct manner. So I will, for my initial posting, comment on the impressive writing skill of Darwin and how “On the Origin of Species” is presented as comprehensible literature. Although this text is remarkable on a variety of levels, being a first time reader I was initially impressed and pleasantly surprised by the style of writing. Darwin allows all readers, regardless of their academic background, to understand and engage with the material in this text. The average reader is able to connect with and relate to the support that Darwin provides, which in my mind, is further confirmation that Darwin Kicks Butt!
More to come …