Thursday, May 26, 2016

Excerpt from "Progress Debunked": Evolution vs. Birth Control

4. Malthus as a Prophet of Non-Progress.

Suffering and crisis are ineliminible components of the human condition. Resource limitations guarantee that all societies will experience periodic difficulties. If this were not the case, there would be no reason for people to have to adapt, struggle, feel, or think.

As I see it, Malthus discovered a deep philosophical principle. Evil is necessary to life, because it is only through the struggle to overcome it that we become fully human. It is absurd to suppose that the right political or economic system will one day eliminate all evil and struggle from every society in the world. This is not supposed to discourage us from doing good and charitable deeds, but encourage us to pursue them on a local scale. Between us and Malthus lie the twin catastrophes of Fascism and Communism. If Malthus’s Principle was prophetic of anything, it was that world-progressive, utopian ideologies like these are fundamentally irrational.

5. Birth Control: Solution or Mirage?

Granted that all of nature and most societies have been subject to the Principle of Population, might it still not be possible to rationally convince the world to use birth control and finally rid ourselves of this obstacle to progress? Aren’t organizations like Planned Parenthood already trying to do this?

As urbanization continues across the globe, average fertility rates are falling. According to the UN (2010), between 1950 and 1955 the total fertility rate (births per woman) was about 4.95. Between 2010 and 2015, it was 2.36. So it is declining and it doesn’t seem unreasonable, on the face of it, that this trend will continue and eventually free the world from the “Malthusian Trap.”

However, I’m going to argue in the following sections that this is an irrational hope.

Malthus originally argued that the “passion between the sexes” could never be overcome. It is ubiquitous in nature. Every plant and animal species produces, on average, more offspring than can reproduce themselves. This is no surprise on Darwin’s theory of natural selection. Populations that do not reproduce at their maximum rate will always give way to those that do. As we’ll discuss shortly, creative evolution requires mutation as well as natural selection. Without natural selection, mutation leads to uncontrolled variation. Without mutation, a species has no adaptability.

Could it be that the tendency of humans and animals to reproduce exponentially is a hardwired result of evolution? A tendency that is needed for a species to continue to spread, diversify, and adapt? In the following sections I’ll argue that this is indeed the case. I’ll attempt to demonstrate that Darwin’s theory can be stated as a law of nature that mandates a balance between creativity and destruction. On this view, neither progress nor regress is possible in the long run, whether we are talking about plants, animals, or human civilization.

5. Darwin’s Question.

Along with social upheavals, the 18th century Enlightenment created tremendous scientific upheavals as well. As Europe became wealthy on transoceanic trade, specimens of plants, animals, and minerals were brought back from around the world, overthrowing previous theories in geology and biology. Scientists began to speculate that the world was at least millions of years old, that species might have changed over these vast periods of time, and that different species might have even descended from a common ancestor.

The question of the origin of species was divisive. On the one hand you had Biblical history, in which each species was specially created a few thousand years ago. All had to fit on a wooden ark to survive the flood. On the other hand you had views like those of Lamarck, who argued that when any animal used an organ or limb, it would become enlarged, and that if it did not use it, it would shrink and eventually disappear. In this way he supposed that every species had evolved toward greater and greater complexity over millions of years. Neither view seemed satisfactory. The Biblical view didn’t seem to accord with the evidence, and “use and disuse” could only explain size—not things like shape, color, or instinct.
In the mid-19th century, under the influence of Malthus’s Essay, a new theory began to emerge. Young Darwin, as he voyaged from continent-to-continent as the naturalist on board the Beagle, had made special note of how species were distributed across the globe. For instance, finches on the Galapagos Islands were partially-adapted for niches usually filled by other species in other places. In fact, the Galapagos had almost no birds besides finches. There were insect-eating finches, nut-eating finches, cactus-eating finches, and several other kinds, each with a specially-adapted beaks, feathers, and colorings. If a creator had placed these birds here, why only finches? Why not use better-adapted varieties seen elsewhere? Evolution seemed a simpler explanation. Finches were more common on the mainland of South America. If they had migrated to the Galapagos it would explain why there were only finches there, who had adapted to local conditions and now came in so many unusual varieties.

From this observation and several others, Darwin began to speculate on evolution. Taxonomy and comparative anatomy also provided good evidence that most or all species had evolved from a common ancestor. “What can be more curious,” he wrote, “than that the hand of a man, formed for grasping, that of a mole for digging, the leg of a horse, the paddle of a porpoise, and the wing of a bat, should all be constructed on the same pattern, and should include the same bones, in the same relative positions?” The big question was how it had happened. What process had allowed species to change and adapt so meticulously over time? Geologists had been able to explain dramatic geological change through the action of wind, waves, and dust over millions of years. But biology was missing a theory of how complex adaptations arose. Use and disuse didn’t seem to explain anything. Why would using an organ make it grow larger rather than smaller? How had a device as complex and intricate as the eye arose by the chance influence of the environment?

6. The Influence of Malthus on Darwin.

Prior to his reading of Malthus, Darwin “perceived that selection was the keystone of man's success in making useful races of animals and plants. But how selection could be applied to organisms living in a state of nature remained for some time a mystery” (Autobiography, 1887). Animal breeding by humans had succeeded in creating animals as different as Dachshunds and Great Danes from a single common ancestor. Could there be a similar process by which nature built up new varieties? But how could the random processes of blind nature compare with careful selection by animal breeders?

In his Autobiography, Darwin explains his breakthrough reading Malthus:

In October 1838, that is, fifteen months after I had begun my systematic enquiry, I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The result of this would be the formation of new species. Here then I had at last got a theory by which to work; but I was so anxious to avoid prejudice, that I determined not for some time to write even the briefest sketch of it. (Darwin, 1887)

He called this process by which favorable variations were preserved natural selection, by analogy with the process of artificial selection that humans use to make new breeds of animals and plants.

Because all animal and plant populations grow exponentially, they are subject to constant pressures from lack of resources. These pressures cause the less well-adapted to die or have fewer offspring than others. If a certain plant produces a hundred seeds, on average only one can grow to maturity to produce its own seeds, and this one will tend to be better-adapted. In this way the better-adapted survive and pass on their traits.

But Darwin knew that natural selection alone could not account for evolution. Selection was a purely destructive force. It did not create new varieties but only destroyed the ones that were less well-adapted. In order for natural selection to produce to species, it needed a constant supply of new variations to work on. And these variations had to be heritable, or they could not lead to permanent change in the species.

Today we know that heritable traits are coded in DNA. Mutations in DNA create new variations, providing raw material for natural selection. In Darwin’s day, the mechanisms of inheritance were obscure. He devoted several chapters of the Origin of Species to arguing, using evidence from animal breeding and natural history, that heritable variation was common throughout the plant and animal kingdoms, even if its details were still unknown.

7. Darwin’s Theory in a Nutshell.

Biologists have since refined Darwin’s theory to a set of three conditions, known as Lewontin’s Criteria. They are based on a mathematical formalization of Darwin's theory by Mary Williams published in 1970. In the same year the biologist Richard Lewontin published a paper, “The Units of Selection,” in which he points out that natural selection is guaranteed to occur in any population which satisfies the following three criteria:

1. Different individuals in a population have different mental and physical traits (“Variation”).
2. This variation is heritable (“Heritability”).
3. Different variants have different rates of survival and reproduction (“Differential Fitness”).

It is widely recognized among biologists that all systems which satisfy these conditions undergo natural selection.

Variation is also referred to as diversity. If all the individuals in a population have the same traits, there can be no evolution. Natural selection only works on differences.

Heritability just means that traits are passed from one generation to the next. If the traits aren’t passed down, then new variations will be lost.

Differential fitness refers to the fact that some traits will spread more quickly than others. Fitness is a biological term meaning average number of offspring per parent. Among humans, if the average couple has 2 children, that will be fitness 1. If the average couple has 4 children, that’s fitness 2. An average of 1 child means fitness of 0.5. Traits with a fitness above 1 will quickly spread and come to predominate.

If you add mutation to the picture to provide new variations, you get evolution. In fact one can combine these conditions with the mutation requirement and state evolution as a single condition:

Evolution is when heritable variations (mutations) arise that make a difference to how many offspring are produced.

This is Darwin’s entire theory of evolution in a nutshell.

Say you’ve got a mutation that causes a certain organism to produce slightly more offspring. If this mutation is passed down, then it’s offspring will also have more offspring. The spread of this variant will thus be exponential. Since there are limited resources, by Malthus’s Principle, other variants will decrease in the population until they disappear.

Ultimately, Darwin’s theory explains the mystery of why every organism tends to reproduce at an exponential rate.

8. A Note on the Terminology of “Selection.”

Differential fitness is commonly referred to as “selection” by biologists, and I will use the same term here. Originally, Darwin drew a sharp distinction between natural and artificial selection, because his challenge was to argue that species could evolve without the intervention of a higher being. It was well known that animal breeding—“artificial selection”—could produce from the same species animals as different as St. Bernards and Terriers. Darwin had to show that this process was possible in the wild, and he called this “natural selection.”

In this book we are discussing selection among humans. When the distinction between natural and artificial selection is unnecessary, I will simply use the term “selection,” which refers to either kind. “Natural selection,” as with animals, will refer to selection due to untimely death, individual mate choice, or difficulty reproducing. However, to maintain continuity with past literature on human evolution, artificial selection of humans will be referred to as “eugenics.” This term will be used for any scenario where the natural processes of survival, mate choice, or reproduction are interfered with by custom, law, or decree.

9. Evolution and Birth Control.
Many see natural selection’s way of doing things as unnecessarily cruel. In order for it to work, most offspring must fail to reproduce. In the modern Western world, we try to challenge this perceived cruelty by reducing the number of births. Birth control, it is believed, is simply a rational way to reduce overall pain and suffering.
Animals in the wild have no choice. They act according to instinct and suffer without contemplating the big picture. Many suppose that birth control helps separate us from animals, that it makes us special. In fact many scientific authors like to say that we’ve overcome Darwinian evolution. “If each family had only two children,” writes biologist Cavalli-Sforza triumphantly, “there would be no natural selection.” Richard Dawkins writes in The Selfish Gene (1978): “We are built as gene machines and cultured as meme machines, but we have the power to turn against our creators. We, alone on Earth can rebel against the tyranny of the selfish replicators.” Steve Jones, in The Language of Genes (1995) writes: “It may even be that economic advance and medical progress mean that humans are almost at the end of their evolutionary road, that we are as near to our biological Utopia as we are ever likely to get.”

The reality is that most of humankind is still subject to natural selection. Most societies, religions, and individuals have fertility rates above two. In fact most preindustrial cultures explicitly discourage birth control. (For a variety of detailed examples see Carol P. MacCormack and Marilyn Strathem, eds., Nature, Culture, and Gender, 1982.) During the period 2000-2005,there were 33 nations (totaling 720 million inhabitants) with average birthrates of at least 5 children per female, 17 nations (totaling 240 million people) with average birthrates of at least 6, and 3 nations (totaling 45 million people) with birthrates of at least 7. These birthrates are comparable to those in the preindustrial West, which were generally in the 5-8 range. These nations are growing significantly faster than the rest of the world, with annual growth rates between 2 and 4.5%, compared to the world average of 1.17%. Even within the United States, there are religious groups, such as the Mennonites, who oppose birth control on principled grounds and thus have a consistently higher fertility than the rest of the country.

At the same time, many industrial countries have birth rates below replacement levels, so that their populations are in fact declining at exponential rates. Countries with fertility rates below 1.5 children per female include China, Japan, South Korea, Lithuania, Ukraine, Spain, Italy, Hungary, and Austria. In fact, the European Union as a whole has an average fertility rate of about 1.50. Assuming that children tend to adopt the birth control practices of their parents, it appears that natural selection will eventually lead to the predominance of those cultures that resist the use of birth control.

Many express the hope that by industrializing and educating other nations we may eventually reduce all fertility rates below two. What people usually do not stress is that every society in the entire world would have to consent to this for it to work in the long run. If only one society of, say, a million people retained a birth rate of three children per family, this society could number in the billions within four centuries. If the Amish maintain their current rate of population growth, German-speakers will outnumber English-speakers in North America within two hundred years.

This is natural selection at work. A similar explanation may account for the disappearance of Pagans and Gnostics who used abortion and infanticide as means of family planning in late Antiquity, and the spread of early Christians who discouraged these practices.

I am not sure how to prove that birth rates cannot be lowered to replacement levels in every society worldwide. It is conceivable that a world government might be put in place that sterilizes all women after two children, for example. Personally I find such schemes abhorrent. Rest assured if that happened you could count me among the freedom fighters. But to gain a better understanding of the principles of evolution, let’s assume for the sake of argument that birth rates have been reduced to two everywhere and indefinitely.

To begin with, notice that in this scenario there would be no natural selection. Everyone would reproduce at the same rate, so there would be no differences in fitness. New mutations would arise, but they would give no one any advantage or disadvantage. Instead, every generation would accumulate more random mutations and pass them on.

How do we know there would be mutations? We know because inheritance is not perfect. When DNA is copied, there are sometimes mistakes. It is estimated that about 400 mutations occur between each generation of human. Most of these mutations don’t make any difference. A few are harmful, and a very rare few are beneficial. It is much more common for mutations to have detrimental effects than beneficial effects. Mutations are more often harmful than helpful for the same reason that cars tend to run worse, and not better, as the get older. Random changes to any structure will tend toward disorder, as we know from the theory of thermodynamics in physics.

In most cases these harmful mutations are eliminated by natural selection. As I’ve mentioned most plants and animals produce many more offspring than can survive or reproduce. Typically only 1-30% of offspring succeed in reaching adulthood and reproducing themselves. In this way mutation and natural selection keep each other in check. Mutation provides new variety, natural selection eliminates unfit varieties.

Birth control, in other words, would appear to disrupt the balance between mutation and natural selection. That this might be so has been feared for over a century. A shallow understanding of these principles of evolution, however, led to the infamous eugenics movement. It is worth pausing to consider the history of eugenics before proceeding, because nothing has done more to muddy the waters of the debate over whether and how Darwin’s theory can be applied to humans.

10. Eugenics as Tyranny.

Eugenics is a social movement responsible for the sterilization of millions in the early-to-mid twentieth century, and used by the Nazis to justify the murder of millions. There are still eugenic societies around the world, though most have been forced to keep a low profile in the wake of the atrocities of World War II.

Let me clarify my personal views before we go any further. I am not a eugenicist in any sense of the word. Eugenics is based on the idea that humankind as a whole can be improved or degraded. I don’t believe either is possible. Freedom, family, and universal love are held as sacred values by all religions. In order for these to be possible, each individual must be valued as the incomprehensibly complex, creative, and spiritual being that he or she is. Any and all state-run programs that interfere in human reproduction—one of the highest expressions of human love and creativity, the bringing into the universe of a new incomprehensible being—are intrinsically evil and should be opposed. This includes any program that impedes a human’s right to reproduce, whether for the purpose of limiting the world population, or for the purpose of “improving” its genetic stock. Both of these goals have been integral tenants of the eugenics movement.

The origin of the most infamous eugenic societies lay in the late 19th century, before the mechanisms of heredity were very well understood. Francis Galton, a statistician and sociologist, worried that the poor were outbreeding the “gifted” in his influential book Hereditary Genes (1887). Karl Pearson, another statistician, agreed that we needed to “check the fertility of the inferior stocks” (The Grammar of Science 1892).

Reactions varied. Many put up stalwart resistance. In his 1893 essay “Evolution and Ethics,” T.H. Huxley, an ardent supporter of Darwin’s theory, condemned the idea of eugenics because it failed to take into account both its impracticality and the immoral effects it would have on society. Arguing for its impracticality he wrote:

I doubt whether even the keenest judge of character, if he had before him a hundred boys and girls under fourteen, could pick out, with the least chance of success, those who should be kept, as certain to be serviceable members of the polity, and those who should be chloroformed, as equally sure to be stupid, idle, or vicious. The “points” of a good or of a bad citizen are really far harder to discern than those of a puppy or short-horn calf; many do not show themselves before the practical difficulties of life stimulate manhood to full exertion.

And against its morality he argued that it would require “preternatural ruthlessness” and “drastic thoroughness” and that “human society is kept together by bonds of such singular character, that the attempts to perfect society after his fashion would run serious risk of loosening them.”
But the movement only grew in strength. In 1922 the social critic G.K. Chesterton was moved to publish a lengthy and brilliant—if somewhat unscientific—refutation of eugenics entitled “Eugenics and other Evils.” He argued that love is personal and should not be regulated by the state. He called any such regulation “tyrannical” and rhetorically asked to whom “such risks of tyranny could be trusted.” He pointed out, quite rightly, that the “complexity [of heredity] must be nearly unfathomable ...”
But the heavy mathematical artillery, as it unfortunately happened, fell into the lap of eugenics. Mathematicians J.B.S. Haldane and R.A. Fisher—who were skeptical of eugenics—were the first to develop a mathematics describing natural selection among discrete (Mendelian) genes. This meant that processes of natural selection and mutation could finally be combined into one model, an important step in filling in the gaps in Darwin’s theory of inheritance. But the most influential mathematical biologist was the eugenicist Julian Huxley, who wove together Fisher and Haldane’s theories, field biology, social anthropology, statistics, and genetics into his masterwork, Evolution: the Modern Synthesis in 1942. Huxley was vice president of British Eugenics Society from 1937-1944 and President from 1959-1962. He helped encourage many of the mass sterilizations that happened throughout Europe and North America during this time.

After World War II eugenics became associated with Nazism, so Huxley coined the term “Transhumanism” for it in his 1957 essay, and the society changed its name to the Galton Institute in 1989.

In 1964, Huxley published Evolutionary Humanism, which argued:

To effect [future improvements of our species we] must first of all check the processes making for genetic deterioration. This means reducing man-made radiation to a minimum, discouraging genetically defective or inferior types from breeding, reducing human overmultiplication in general and the high differential fertility of various regions, nations, and classes in particular. Then [we] can proceed to the much more important task of positive improvement. (p. 252)

Nevertheless, eugenics continued to decline in the wake of the horrors of Nazism, though few attempts at scientific, quantitative refutation were attempted. Stephen Jay Gould's Mismeasure of Man (1981) did challenge the use of IQ testing that the eugenic program depended on. Gould argued that people were attempting to reify a concept that had no objective basis, and that rank-ordering complex things like intelligence was inherently nonsensical. Political tracts such as Not in Our Genes (1984) by R.C. Lewontin, Steven Rose, and Leon J. Kamin offered woefully indecisive objections that nevertheless few dared to publicly question:

We reject [the nature-nurture] dichotomy. We do assert that we cannot think of any significant human social behavior that is built into our genes in such a way that it cannot be modified and shaped by social conditioning ... . Yet, at the same time, we deny that human beings are born tabulae rasae ..." (267)

Despite the lack of any truly rigorous analysis, the view that heredity is irrelevant to discussions of the human population has become the public consensus among scientists. This has become very clear in the wake of the indignant reactions to Herrstein and Murray’s 1994 book The Bell Curve, which presented evidence that IQ was heritable, differed among races, and had a measurable effect on future income.

The debate over IQ measurements and race is ultimately what logicians call a red herring, a distraction from what was originally at stake. What of the eugenicists’ original concern, namely, that modern Western society lacks natural selection to check mutation? The fear of raising further outcries has discouraged critical discussion. As far as I can tell no reasoned consensus about human evolution has been reached.

11. Can Mutation be “Overcome”?

Let’s return to Julian Huxley’s original point, which was the question of whether humanity can reach utopia when our DNA is constantly mutating in ways that are usually harmful. Huxley believed that we must control our population to avoid running out of food. At the same time he saw that birth control would weaken the force of natural selection, which was why he wanted a program of eugenics to eliminate harmful mutations from the human gene pool.

A few subsequent authors seconded this proposal. In his 1978, Pulitzer-prize winning On Human Nature, biologist E.O. Wilson brought up the apparent problem of human mutation and said that eventually we will have the knowledge to put in place “democratically contrived eugenics” to counteract it.

Harvard biologist Stephen Jay Gould made a heroic—if unsuccessful—attempt to challenge this assumption in his posthumous tome The Structure of Evolutionary Theory:

This situation supposedly raises a forest of ethical questions about double-edged swords in the cure of diseases arising from genetic predisposition, the spread of genes for poor vision in a world of cheap eyeglasses, et cetera ad infinitum. (Pardon my cynicism based on some knowledge of the history of such arguments, but the neo-eugenical implications of these claims, however unintended in modern versions, cannot be ignored or regarded as just benignly foolish.)
This entire line of fallacious reasoning, with all its burgeoning implications, immediately collapses under a speciational reformulation. Once people understand Homo sapiens as a biological species, not a transitory point of achievement, the apparent paradox disappears [...] Most species-especially those with large, successful, highly mobile, globally spread, environmentally diverse, and effective panmictic populations-remain stable throughout their history [...]. Change occurs by punctuational speciation of isolated subgroups, not by geologically slow anagenetic transformation of an entirety.

Gould is referring to a theory in evolutionary biology that large populations do not show very much evolutionary change. This theory is controversial and opposed by a number population biologists, since it neglects the greater flux of new mutations that a large a population can select from. Be that as it may, Gould’s objection does not actually apply to the case of humans using birth control. There are no examples of any species aside from humans that are not continually subject to natural selection. For a species to remain “stable” as Gould puts it, natural selection must act continually to counter mutation, as all textbooks in population biology teach. (For a simple mathematical argument, see Appendix 2).

So if Julian Huxley and E.O. Wilson’s arguments remain untouched, are they and the other quieter eugenicists right then? Are we bound to control human mutation lest it spiral out of control?

Let’s remember once more that we are talking about a hypothetical scenario where all birth rates in the world have been reduced to two. This does not seem doable except by world tyranny, but we are assuming it is possible for the sake of argument.

To control human mutations by engineering, we would have to genetically engineer every new baby on the planet. Even if we could afford this, how can we be sure our method for reducing mutations is infallible? It’s been shown that multiple genes code for multiple things. What about sexual recombination giving us new genetic linkages and traits? Maybe one way to stop all mutation would be to simply clone each generation from a DNA database. But what isn’t horribly wrong with such a scenario? Every generation would be biologically the same. No new genetic combinations could be made, for fear of mutation. Not only is this plan implausible, but also monstrous.

If anyone sets up a world government this controlling, let’s overthrow it.

But where does this leave us? Is humanity hopeless? Quite the contrary. We are back to Malthus’s original conclusion. You cannot completely eliminate suffering and evil from life. Mutation carries with it both good and bad. It is the source of new talent, new genius, and new diversity among humans. To rid ourselves of mutation would be to rid ourselves of most of what is unique and creative about individuals. But in our universe there is no free lunch. The benefit of mutation comes at a price. Many mutations are bad and lead to vice and incompetence. If you look at the big picture, I think you will see that the good and evil in humanity are closely intertwined, and that this is precisely what makes humankind so wondrous.

Transhumanists argue that the human genome could simply be engineered like any other technology, and thus could continue to change and evolve without having to worry about mutation and selection. But such fantasies are far-fetched on close inspection. The human genome is incredibly complex, and it isn’t clear that anyone could hold the whole thing in their head in order to design a new human. Most machines that we make, including computers and cars, are far less complex than the human body, but when we are designing new versions, it is always necessary to built prototypes and test them to see if they will work. Invariably they do not work except after a lot of testing and redesigning. But nothing like this would be ethical for humans. We would obviously not want to raise an entire human being as a “prototype” to be destroyed if he or she does not function properly.

As a matter of fact, it is no more possible to calculate the functionality of a new technology before it is built and implemented, than it is to calculate the fitness of a given organism. Any engineer will tell you this. It would appear that human invention depends on selection as essentially as biological evolution does.

Could it be that anything that evolves must do so through mutation and selection, including culture and technology? I want to argue that this is true. Relying on our culture alone for adaptability will run into the same “problems” (I’d prefer the term “realities”) as relying on biological evolution. Under the heading of culture I mean to include technology, science, and all human ideas and artifacts. In the next chapter I will expand on the idea that culture is subject to natural selection. In brief, Lewontin's criteria apply to culture and thus culture is constrained by Darwin's Law as strictly as biology. All self-replicating systems, in fact, are subject to both Darwin's Law and Malthusian resource limitations. Ultimately, this will provide us with a general theory to describe the fundamental logical inconsistency in the notion of progress. 

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