* One of the more controversial aspects of modern evolutionary thought is the effort to apply evolutionary notions to behavior, an effort originally referred to as "sociobiology" and now generally called "evolutionary psychology". Under either label, it's provoked a great deal of argument both within and without the evolutionary science community. The community also went through a period of controversy over, of all things, the rate of evolution, with the dispute over what was called "punctuated equilibrium" becoming noisy for a time. In the meanwhile, work on deciphering the genome continued -- and our level of knowledge now promises to create even louder and angrier controversies.
* Fueled by the work of Hamilton and Williams, as well as animal behaviorists such as Tinbergen and Konrad Lorenz (1903:1989), the 1960s saw the emergence of something of a "cottage industry" of research on the evolutionary development of behavior, both of animals and of humans. The idea was not new, having been visited by both Darwin and Thomas Huxley, but it had never been given such a high level of attention before. The result was the introduction of what became known as "sociobiology", or (particularly when applied to humans) "evolutionary psychology", the preferred term these days.
The exercise ignited with a book titled SOCIOBIOLOGY: THE NEW SYNTHESIS, published in 1975 by Harvard entomologist Edward O. Wilson (1929:2021), which provided a comprehensive survey of what was known in the field at the time. Its comprehensiveness made it an intimidating slog for nonprofessionals, but Wilson sensibly followed it up in 1980 with a simplified version for general readership, ensuring that it reached a wide audience.
Wilson, an expert on social insects, particularly ants, read Hamilton's paper on the evolution of altruism during a train trip. It made Wilson angry, since some unknown British graduate student was making major claims about the genetic basis of animal societies, and Wilson didn't think Hamilton -- or for that matter many other biologists -- touched his own level of expertise in the subject. However, Wilson couldn't see any flaw in Hamilton's argument, and by the end of the train trip, Wilson was sold, making investigation of sociobiology one of his core interests.
SOCIOBIOLOGY was a thorough text, consolidating what was in circulation in the field at the time, with Wilson's own spin on the matter. Wilson covered the range of behavior in the animal world, which caused no great controversy, but when he applied the same reasoning to humans, he set off a storm -- for example, by describing how selection pressures ensured males were genetically inclined to be promiscuous, scattering their genes, while females had a genetic inclination to be selective, since they invested so much energy in bearing and raising their children.
Such notions had a tendency to sound as like biological justifications for traditional sexual roles -- the guys could screw around, while the women were faithful and stayed home to take care of the kids -- and Wilson was not the sort of person to always be overly sensitive in how he presented them. Wilson, a bright, polite, and gracious Alabama boy to those who knew him, was very driven, coming across as confrontational and dogmatic in print. He had been raised Baptist, and though he had lost the faith, he retained its sense of conviction. Comments such as suggesting that ethics "should be removed temporarily from the hands of philosophers and biologicized" earned him derision. Humans, his critics insisted, could not be reduced to beasts, prisoners of genetic determinism, driven solely by instincts, incapable of moral choices or improvement; nature could not be used as a moral role model.
That was an exaggeration of Wilson's position, and he insisted that he wasn't trying to attack traditional ethics. What he claimed was that the old dispute over "nature versus nurture" had swung unrealistically to the "nurture" position. There were valid reasons for why that had happened; Victorian commentaries on the behavior of females or various ethnic groups make odd reading today, coming across as obviously nothing more than prejudice masquerading as science. Rejecting the chauvinism of the past was clearly a good thing -- but taken to an extreme, it promoted the dubious idea that instinct had no influence on behavior at all, and that behavior could be reshaped as much as needed to conform to any desired goal.
Wilson was bitterly attacked from many directions, the critics including colleagues in the scientific community. Richard Lewontin led the charge against Wilson, being quickly joined by Stephen Jay Gould. Gould labeled many of the evolutionary scenarios of sociobiologists as "just so" stories, and Lewontin and Gould blasted Wilson as a throwback advocating discredited notions: "Wilson joins the long parade of biological determinists whose work has served to buttress the institutions of their society by exonerating them from responsibility from social problems."
Wilson hit back, describing Lewontin and Gould in so many words as "deep in the Left outfield" Marxists engaged in what would now be called a "correctness exercise". Wilson was not simply throwing rocks, the New Left was still prominent among academia in those days, both Gould and Lewontin were unapologetic Reds: Gould was a "Red diaper baby", born and bred Red, and Lewontin was noted for his inability to open his mouth without ranting about the class struggle. In addition, Gould felt a personal obligation to police any attempts by the evolutionary science community to resurrect Social Darwinism, genetic determinism, and eugenics, and he tended towards the zealous in the matter. Anyone who had actually looked through SOCIOBIOLOGY would have hardly found it all that outrageous in general, since even the popular abridged version tended toward the dry and academic in tone.
Others took an even dimmer view of Wilson. In 1978, protesters who labeled Wilson as a racist set on him during an address at a science symposium and dumped a pitcher of water on his head. The audience gave Wilson a standing ovation in sympathy; Gould was in the audience and denounced the attack.
* The controversy actually could not be simply reduced to a simple morality play, with the white hats on one side and the black hats on the other. It is obvious that humans have instinctive behaviors, in many ways not so different from those of animals, particularly their primate relatives. Those who have spent much of their lives in various organizations can't help but think, at least on occasions when things aren't going well, of how their social systems resemble that of a baboon troop, with dominance games played to establish hierarchies. Organizations that go to lengths to proclaim they are above such behavior can turn out to be nastier in this regard than the average.
Very few people honestly believe there are no innate behavioral differences between men and women, though there's little consensus on what those differences are. However, it is also obvious that humans are capable of thinking things out, and adhering to ethical codes that demand conduct superior to that of animals. It is an unarguable fact, a fundamental basis of systems of law and justice, that humans can decide between right and wrong. Though they do so inconsistently in practice, nobody sensibly advocates that since humans are another species of primate, we should just then throw up our hands and declare it's okay to act like baboons. When people do act like baboons, few are okay with it.
On the other hand, we can't simply declare our instincts irrelevant. The revolutionary regimes of the 20th century often believed that their citizens were simply "blank slates" that could be remolded to make them obedient tools of the state. The effort was not merely repressive and authoritarian; it was also futile. It was commented after the fall of the USSR that the Soviet Union had three generations to build the "New Soviet Man", and the effort was as plainly a fairy tale as Lysenkoism.
The question of nature versus nurture, then, is perfectly legitimate, even important. It can certainly be argued that if we hope to triumph over our instincts, we must understand them first. There still is the issue of how much insight MET can provide into such matters. Hamilton's analysis of altruism was clearly useful, since it neatly resolved a long-standing evolutionary puzzle. The problem is that it works neatly for ants, with their machine-like behavior, but not quite so neatly for humans, whose behavior tends to be highly flexible and sometimes very unpredictable.
Humans carry a "meat supercomputer" in their heads, with many capabilities far beyond the reach of any machine we can build at present, and it is certainly true that our brain has significant hardwired functions that we need to understand. For example, adults typically find it difficult to learn another language, while an infant does it from scratch, without any prior training or experience. This implies a spectacular level of elaboration in human instincts; the meat supercomputer comes preloaded with some powerful software.
However, as a powerful computer, much more flexible than the highly instinctive brain of an ant, the human brain is reprogrammable in unbounded ways. Evolution produced that supercomputer, but it only happened because it enhanced our ability to survive and procreate. The fact that a supercomputer that arose because it helped us survive also gave us the physics of Einstein and the music of Mozart seems to have been, from our point of view, just an added benefit.
Is it realistic to think we trace all human behavior back to evolutionary drives? Or do humans sometimes just unpredictably do whatever they damn well please? There is clearly some fuzzy dividing line between what can be sensibly said about instincts and their origins -- and what amounts to "just so" stories, neither provable nor disprovable, providing no insights that leave us any wiser than we were before, reducing the exercise to something like talk-show pop psychology. The argument is essentially over where that dividing line might be drawn.
Wilson remained committed to his ideas and continued to refine his work. He indeed managed to establish converts to his vision, which at root he claimed simply meant: Biology matters. Wilson did not avoid controversy, writing that religion was "an illusion fobbed off on us by our genes" and offering the notion that a new religion based on evolutionary insights was in the wings. That idea didn't get many takers, either from religion or its detractors.
BACK_TO_TOP* Stephen Jay Gould became one of the most high-profile evolutionary biologists, his books often making the best-seller lists and leading to appearances on talk shows. His high public profile led some of his colleagues to regard him as more of a science writer and self-promoter than a scientist. Like Dawkins, Gould was inclined towards controversy, and working with Museum of Natural History paleontologist Niles Eldredge (born 1943), he produced it in quantity by proposing what became known as "punctuated equilibrium".
Even Darwin had noted that the fossil record was inconvenient to his theory in some ways, suggesting that though there was a clear succession of forms, species seemed to remain stable for long periods of time. For example, the oldest known fossil of a bat is about 50 million years old, and is a perfectly respectable bat. Darwin chalked this up to the sketchiness of the fossil record, and most after him maintained that notion, remaining committed to his notion of evolution by slow steps or "gradualism". Bats, for example, are small, relatively fragile, tend to live in environments where fossilization doesn't often happen, and so fossil bats are very rare. What Eldredge and Gould proposed was that the fossil record was correct as known: that species went through rapid bursts of evolutionary change and then settled down to a fairly static existence.
The quarrel over punctuated equilibrium became loud and noisy, but it seems only because it was made to be. Gould and Eldredge presented their case as if it were revolutionary, and their critics accused them of rocking the boat, mocking punctuated equilibrium as "punk eek" or "evolution by fits and starts". Some were ruder, calling it "evolution by jerks" -- with Gould sniping back at his adversaries, referring to "evolution by creeps". Creationists unsurprisingly jumped into the fray, claiming it proved that evolutionary science was in a state of complete disarray.
In reality, the idea that species would emerge through rapid change and then settle down to a relatively static existence was nothing new. As mentioned earlier, George Gaylord Simpson had promoted the idea, and in fact it had been proposed by the astoundingly thorough Darwin in the fourth and later editions of THE ORIGIN OF SPECIES:
BEGIN QUOTE:
Many species once formed never undergo any further change ... and the periods, during which species have undergone modification, though long as measured by years, have probably been short in comparison with the periods during which they retain the same form.
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Darwin strongly emphasized that natural selection works in a gradual way, but he didn't mean that it worked at the same rate at all times in the history of a species. 100,000 generations is plenty of time to obtain considerable evolutionary change through gradual changes screened by selection pressures; after all, that's a near-invisible change of a thousandth of a percent per generation. Given a fairly ordinary small organism with a generation time of a year, 100,000 generations is only 100,000 years. Most people would be incredulous at that phrase "only" 100,000 years, since that's a vast interval by human standards, twenty times longer than recorded history -- but it almost doesn't register in the geological record. It's effectively instantaneous.
Even a million years is a relatively short time by geological standards, but a million generations could result in massive changes in organisms. Imagine a video of the successive generations of an organism along a continuous line of its evolution, with one frame per generation and a reasonable video rate of 30 frames a second. The whole video would last over nine hours; we would certainly be able to see visible changes in time scales of a minute -- 1,800 generations -- and expect to see considerable transformations in an hour -- over 100,000 generations. The organism in the final frame could easily be "morphed" all out of recognition from the one in the first.
Could natural selection form a modern bat from a completely flightless ancestor in a few million years? As far as MET is concerned: sure, why not? In fact, as Gould and Eldredge pointed out, as far as MET is concerned, it would be baffling if it took tens of millions of years, since that would imply selection pressures so very low, adaptive changes in organisms in invisible millionths per generation, that they would be lost in the selective noise, too insignificant to be promoted or weeded out. There's every reason to expect that the evolution of a particular adaptation should be rapid, at least by the generous notions of the geological timescale. The interval between an australopithecine and a modern human is only about three million years, but over that time the brain size almost tripled -- an adaptation that produced our biological supercomputer, as or more dramatic as the bat's development of flight. Conservatively assuming an average generation time of 25 years, three million years is only 120,000 generations.
Furthermore, a notion that evolution might take place rapidly in small, isolated branch populations of a species went back to Sewall Wright, and Ernst Mayr had suggested in his founder principle that such isolated populations might quickly evolve and then displace their large parent populations in short order, at least on geological terms. In this view, the evolutionary progression of the branch species not only took place with relative rapidity, it took place off the main stage in a small population -- meaning the odds of finding transitional fossils would be low, while the odds of finding fossils of the stable main population would be high. The transition from one species to the next would seem, in geological terms, instantaneous.
Not all biologists thought much of the founder principle, but Gould and Eldredge actually had it as part of their brief, and knew it wasn't news. They were accused of going back and forth over their ideas, stressing their radicalness, to then soften their tone in the face of loud criticisms -- as well as the inclination of creationists to exploit the controversy -- and say there was nothing really radical about them at all.
It is easy to exaggerate the disputes of academics. There are likely to be differences of opinion on matters great or small in any field of endeavor, and though the disputes may be polite, with wagers placed between friends, there are people who don't know how to express the slightest difference of opinion except as a quarrel. Academics may conduct bitter lifelong feuds over matters so nitpicking that outsiders can't even figure out what the fuss is about, along the lines of the wars of the Liliputians in Jonathan Swift's GULLIVER'S TRAVELS, with "Big-Enders" and "Little-Enders" murderously fighting it out over which end of a soft-boiled egg to break. Swift was specifically mocking religious crusades, but as a college dean he was only too familiar with the similarly Liliputian quarrels of academics.
In practice, even the noisiest fighting is much more smoke than fire. As has been said in another context: If they were serious, they'd kill each other. If the disputes of evolutionary biologists were diverging from a consensus instead of converging towards one, there would be a problem -- but though there was a time when that was the case, it hasn't been so since the end of the First World War.
In hindsight, the whole feud over punctuated equilibrium was never any more than a tempest in a teacup. To the extent that there were issues, they were simply a debate among the evolutionary science community over details, and of no particular interest to outsiders. Why it became such a public dispute seems to have been a matter of the personalities involved -- Gould was fond of controversy, inclined to fast-&-loose rhetoric -- and the interest of the popular science media in playing up the dispute.
BACK_TO_TOP* While evolutionary biologists debated and refined their game strategies, biochemists continued to probe the molecular basis of life. It wasn't until the late 1960s that the evolutionary biologists and biochemists began to interact: before that, the two groups had been isolated or, in some cases, even mutually hostile.
One of the problems was that though biochemists had cracked the genetic code in principle in the 1950s, they really couldn't obtain much practical leverage off their knowledge early on. It's a typical story in modern science and technology: it usually takes a few decades to take a breakthrough concept and turn it into something that works. Even in the mid-1960s, biochemists still lacked the tools needed to actually read the genetic messages encoded in DNA. Traditional chemical analysis was largely useless for this task, since it could not give information on the specific sequence of base pairs in DNA.
By the end of the decade, biochemists had finally been able to isolate a single gene, and then synthesize a single gene. Using "restriction enzymes", by the early 1970s they were able to create "recombinant DNA" -- that is, DNA featuring sequences spliced together from several different sources -- and insert a new gene into bacteria. These experiments established the basis for the two fundamental recombinant DNA techniques of "cloning" and "sequencing". In cloning, genomes were chopped into segments with restriction enzymes, and then the segments were spliced into the bacterial cells, which then produced the protein specified by the foreign genetic sequence. When a bacterium with a foreign genetic sequence reproduced by fission, it duplicated its new genetic sequence as part of its genome. Further generations of fission led to a population of identical "clones".
A number of techniques were developed to then obtain the sequence of bases in DNA by researchers such as Fred Sanger (1918:2013) and Walter Gilbert (born 1932). Initially, deciphering even small genes took a good deal of time and effort, but the technology improved rapidly and soon biochemists were able to decipher important genes of the human genome.
The logical next step was to decipher the entire human genome. A rough map was available by 1987, but that was a simple task compared to the full decoding of all 3 billion bases in the human genome. The task seemed impossible for the technology at that time. Initially, work focused on fully deciphering simple genomes, such as those of bacteria -- with a few million bases -- by breaking the bacterial genome into random fragments, sequencing each fragment, and then merging the results. After acquiring experience, it seemed more likely that ongoing improvements in sequencing technology made the prospect of decoding the human genome more plausible, and after a few years of discussion and preparation, the "Human Genome Project" was formally initiated.
The Human Genome Project was formally launched in 1990. At the outset, there were those who judged the goal too ambitious, pointing out that the plan specifically required improved gene sequencing technologies, with much higher speed and lower cost, and it seemed too much like wishful thinking that such improved technologies would become available as projected. Fortunately, the projections turned out to be, if anything, too conservative, and the human genome was finally deciphered in 2001. By that time, the genomes of a number of other organisms had been deciphered, and the list is now growing rapidly.
The improvements in our knowledge of our genome and the genome of other organisms already led to elementary "genetic engineering" efforts, which was initially focused on "transgenic" organisms -- involving the splicing of genes into crop plants and domestic animals genes from other, sometimes wildly unrelated organisms. Such "transgenic organisms" include cowpox viruses modified to generate coat proteins from dangerous pathogens to provide safe vaccines; bacteria that have been spliced with the human gene for insulin, allowing the production of insulin in greater quantities and at lower cost than earlier techniques; and crop plants such as corn that have been spliced with genes from bacteria that produce natural pesticides.
There was great public pushback on transgenic modification, so the focus in the field has shifted to "genetic modification", using improved techniques to tweak existing genes in an organism, instead of importing genes from other organisms. Genetic modification has proven much less controversial, one big reason being that it is impossible to tell if a genome has been modified in such a way, or if it has undergone a natural mutation.
* The deciphering of genes had a direct and major impact on evolutionary science. Traditionally, taxonomists had classified relationships among living creatures through studies of their morphology, but the patterns of genetic sequences in the genes of different organisms provided a much more accurate evolutionary map, confirming the broad lines of evolutionary development, but also showing that some relationships had been misunderstood. For example, until recently zoologists had suspected that large dogs were descended from wolves and small dogs were descended from jackals, but genetic analysis showed that the genomes of even pekinese and yorkshire terriers closely matched those of wolves. It is now clear that all domestic dogs are descended from wolves. Furthermore, there turned out to be patterns in genes that were common, with minor variations, among all organisms and could be used to trace out the patterns of descent and modification.
The deciphering of genes and the creation of transgenic organisms has also revived many of the old worries about eugenics. It is now possible to detect a number of latent hereditary illnesses in a genome, and such analyses are used in genetic screening. Couples who want to marry and have children can be screened to see if they carry any genetic defects that would pass hereditary afflictions, such as Tay-Sachs disease or sickle-cell anemia, on to their children. If they do, they don't get married to each other, or they adopt children instead.
A fanatical eugenicist might insist that people who have such genetic defects shouldn't have children at all, so those defective genes can be eliminated from the gene pool. In fact, most people have a number of potential genetic defects in their genomes, and such strict abstinence would mean the end of humanity. More significantly, although personal genomic analysis for "risk factors" to cancers and other maladies has become something of a popular industry, that exercise has highlighted the reality that it's by no means easy to link specific genes to traits. Except for those individuals with obvious genetic liabilities such as Tay-Sachs disease, such personal genomics analyses are rarely able to do any more than identify a range of vague possibilities of risks; the exercise is seen as dubious at best, quackery at worst, and mostly oriented towards making money off the credulous.
Eugenics is not poised to make a comeback any time soon. However, genetic technology gives us the long-term prospect of eugenics that actually works. The idea of genetically-modified humans is popular in science-fiction stories. Later in his life, Robert Heinlein moved on from his early notions of eugenic selective breeding and created a genetically enhanced superwoman in his popular 1982 sci-fi novel FRIDAY. Hollywood star Jessica Alba got her ticket to stardom playing the genetically engineered warrior Max in the 2000:2002 sci-fi TV series DARK ANGEL. Max had a number of cat genes, which made her extremely agile, but also occasionally had some odd feline influences on her behavior.
At the present time, the notion of a "designer baby" remains science fiction. While genetic engineering technology is advancing rapidly, tinkering with something as complicated as the human genome will have a drastic potential for unforeseen side effects. Who's going to step forward to volunteer their kids to be first?
Still, in principle the time is likely to come, sooner or later, when humans will be able to control their genetic destiny. This obviously presents dangers, but it is also going to be very hard for parents to resist the idea of having children who are healthier, stronger, smarter, and live longer. Evolution to this time has been a blind process; now we are faced with the prospect of being able to direct evolution. The bottle has been opened and the genie will emerge one of these days, whether anyone likes it or not.
BACK_TO_TOP* This document started out as a component of a longer document, titled INTRO TO EVOLUTIONARY SCIENCE, that I originally published in 2008. In 2017, I realized that it really wasn't a single document, instead being more a collection of three related documents that discussed different aspects of evolutionary science. I decided to split the three out into independent documents to make them easier on the reader, and also easier to maintain.
* Sources include:
* Revision history:
v1.0.0 / 01 jun 2017 / Split out from INTRO TO EVOLUTIONARY SCIENCE. v1.0.1 / 01 may 2019 / Review & polish. v1.0.2 / 01 mar 2021 / Review & polish. v1.0.3 / 01 feb 2023 / Review & polish.BACK_TO_TOP
