Introduction
This paper sets out to examine the basic phenomenon of evolution. I propose that the basic principles that govern evolution of life are analogous or the same as those that govern the evolution of human societies. As Dr. Morton Holmes pointed out in a recent lecture at NIH, genetic defects become fixed in a small human population in a similar fashion as do first names.
Generally, when the average person in the civilized world thinks about evolution, they think of Darwin, natural selection and survival of the fittest. Darwin’s theories laid the foundation for thought on evolution but they were written before much of the modern knowledge on life was developed. While Darwin’s theory was published about 150 years ago, it was within the last 40 years that Sabatini observed ribosomes, the key and central component of cellular life, with an electron microscope. In contrast, while the knowledge of evolution in the general population has stagnated or even eroded during the educational decline of the west, major discoveries of genetics have been made. These discoveries have radically altered scientists’ perspective on life and evolution. They have also given surprising credibility to Darwin’s primary straw man in basic biology lessons.
From these recent discoveries, it is even more interesting how the evolution of humanity mirrors the genetic evolution of life. That is to say that the modern evolution of life resembles the early evolution of humanity and the beginning of life resembles the future for humanity.
Finally, while genetics has and will continue to be used to abuse, oppress, and reduce the God given rights of man, I will attempt to use the relatively recent discoveries of genetics to argue a case for morality in an ever more depraved society. [Edit: Oh, that is great coming from you, past self.]
First, let’s discuss popular culture’s idol of evolution, Darwin.
Darwinian evolution
Random variation vs. conservation
The true brilliance of Darwin’s theory ends up being its reliance on a simple idea. This idea is that offspring compete for resources and sometimes, but not often, some of the offspring are different. This naturally occurring variation may give rise to beneficial traits which allow for the slow evolution of different traits that fit different niches in the environment.
Darwin ‘demonstrated’ this idea by finches’ beaks. Many of the finches on the Galapagos Islands had different beaks that allowed the different finches to eat different seeds or food.
Modern biology explains this variation as mutation. The mutations in life primarily occur because of typos introduced by the molecular machinery that replicate the chromosomes. It is interesting to note that recent analysis has found that the majority of mutations that occur are “neutral”. That is to say they do not become fixed (the majority) in a population because of Darwin’s natural selection but because of simple chance.
Natural selection
This is interesting considering that the most popularized phrase stemming from Darwinian evolution is natural selection. This is the other key to Darwin’s theory, where certain traits are selected for by an increased ability to survive. An example using a simple lab experiment with bacteria is depicted in Fig. 1.
Figure 1. “Darwinian evolution” that occurs with antibiotic selection of bacteria.
In this example, the ovals represent bacteria and arrows from one bacterium down to two below represent the doubling that occurs during cellular replication after one generation. After the third generation a selection is introduced. In this case it is a hypothetical antibiotic which kills the majority of the bacteria except for one mutant that is resistant. This mutant will become the dominant form due to the selection. Without the selection, the mutant would have been neutral in this hypothetical case and most likely washed out as a minority. This is the basic principle behind how an organism slowly changes to different forms because of selection. The case given is an extreme one since selection is rarely a zero sum game. In fact, as mentioned selection is mostly neutral (neither for or against).
It is important to note that the mutant arose from a random mutation or change and not in response to the antibiotic selection. It occurred that way in the figure for convenience.
Common descent
One of the most profound and controversial consequences of Darwin’s theory was that of common descent. Though Darwin tiptoed around the idea that it proved man evolved from apes, it was undeniable that his theories supported an idea of common ancestry. His finches all had beaks that evolved from a common ancestor in different directions giving rise to the many varieties. In Fig. 2, this is demonstrated.
It is important to note that the mutant arose from a random mutation or change and not in response to the antibiotic selection. It occurred that way in the figure for convenience.
Common descent
One of the most profound and controversial consequences of Darwin’s theory was that of common descent. Though Darwin tiptoed around the idea that it proved man evolved from apes, it was undeniable that his theories supported an idea of common ancestry. His finches all had beaks that evolved from a common ancestor in different directions giving rise to the many varieties. In Fig. 2, this is demonstrated.
Figure 2. Common ancestry of different strains of bacteria arising from mutation.
Mutations give rise to different strains of a bacterium (depicted as different patterns) over time (or generations). All of these strains share a common ancestor (i.e. the solid gray parent).
The basics of Darwinian evolution have stood the test of time and successfully laid part of the ground work for modern biology. However, the commonly mocked and ridiculed theory of fellow biological theorist Jean-Baptiste Lamarck succeeds in places where Darwin fails. Ironically, at a time when Lamarckian evolution is used as a straw man against Darwinian evolution, the most brilliant biological minds are finding Lamarckian evolution holds an important role in biology and critical role in the early evolution of life.
Lamarckian evolution
The basics of Darwinian evolution have stood the test of time and successfully laid part of the ground work for modern biology. However, the commonly mocked and ridiculed theory of fellow biological theorist Jean-Baptiste Lamarck succeeds in places where Darwin fails. Ironically, at a time when Lamarckian evolution is used as a straw man against Darwinian evolution, the most brilliant biological minds are finding Lamarckian evolution holds an important role in biology and critical role in the early evolution of life.
Lamarckian evolution
Acquired variation vs. environmental
The classic example that demonstrates Lamarckian evolution is that of how the giraffe acquired a long neck. Lamarckian evolution explained the evolution of the giraffe as occurring by the giraffe ancestor stretching its neck for food in a tall tree and acquiring a longer neck. This longer neck was then inherited by the giraffe’s offspring who stretched for even higher fruit until the modern day long necked giraffe developed.
This theory, while perfectly plausible at the time of Lamarck, generally fails due to the now understood transmission of genetic information from parent to offspring. While the example is easily mocked in today’s biology textbooks, the theory’s basic premise of acquired traits deserves better treatment. It is common for bacteria to acquire traits that lead to resistance of antibiotics and increased virulence in people. This is depicted in Fig. 3.
The classic example that demonstrates Lamarckian evolution is that of how the giraffe acquired a long neck. Lamarckian evolution explained the evolution of the giraffe as occurring by the giraffe ancestor stretching its neck for food in a tall tree and acquiring a longer neck. This longer neck was then inherited by the giraffe’s offspring who stretched for even higher fruit until the modern day long necked giraffe developed.
This theory, while perfectly plausible at the time of Lamarck, generally fails due to the now understood transmission of genetic information from parent to offspring. While the example is easily mocked in today’s biology textbooks, the theory’s basic premise of acquired traits deserves better treatment. It is common for bacteria to acquire traits that lead to resistance of antibiotics and increased virulence in people. This is depicted in Fig. 3.
Figure 3. Bacterial transformation example of acquired traits.
Complexifying force
The other side of Lamarck’s theory involved a hard to explain concept. The fact that we may find it hard to relate to is most likely due to Lamarck being an alchemist (the whole fire, water, earth, air schpiel). In simple terms, Lamarck believed the basic processes of life tended and were driven towards complexity. He explained this drive or force in alchemy terms which I’m not going to get into for everyone’s benefit. However, the idea that there is a force that drives life to higher complexity and order is intriguing. It is a thought that fails miserably where Darwin’s natural selection succeeds, but may, similar to his idea of acquired traits, succeed where Darwin’s random variation fails miserably.
Spontaneous generation
The primary consequence of this driving force was spontaneous generation (the emergence of life from non-living components), which Lamarck thought was constantly happening in the environment. We now know that spontaneous generation does not occur with any discernible frequency in the environment. However, it is generally believed that at some point in time (most likely very, very long ago) spontaneous generation did occur.
What is interesting is that scientists using the basic ideas of Darwinian evolution have trouble explaining the evolution of life. There doesn’t seem to be enough geological time. This problem is most apparent when some scientists try to explain life arising on Earth coming from Mars. The transfer being explained by a very large meteorite on Mars kicking up debris containing cells that ultimately reaches Earth. Apparently, this is plausible. Even if it were true, it would only be passing the buck of spontaneous generation to Mars. There is still a need for at least one spontaneous generation event, where ever one wants it to be, to occur to explain life on Earth.
A theory has emerged lately about this early stage in life and during this time the ideas of Lamarck are far more relevant than those of Darwin.
Modern evolution of life
The other side of Lamarck’s theory involved a hard to explain concept. The fact that we may find it hard to relate to is most likely due to Lamarck being an alchemist (the whole fire, water, earth, air schpiel). In simple terms, Lamarck believed the basic processes of life tended and were driven towards complexity. He explained this drive or force in alchemy terms which I’m not going to get into for everyone’s benefit. However, the idea that there is a force that drives life to higher complexity and order is intriguing. It is a thought that fails miserably where Darwin’s natural selection succeeds, but may, similar to his idea of acquired traits, succeed where Darwin’s random variation fails miserably.
Spontaneous generation
The primary consequence of this driving force was spontaneous generation (the emergence of life from non-living components), which Lamarck thought was constantly happening in the environment. We now know that spontaneous generation does not occur with any discernible frequency in the environment. However, it is generally believed that at some point in time (most likely very, very long ago) spontaneous generation did occur.
What is interesting is that scientists using the basic ideas of Darwinian evolution have trouble explaining the evolution of life. There doesn’t seem to be enough geological time. This problem is most apparent when some scientists try to explain life arising on Earth coming from Mars. The transfer being explained by a very large meteorite on Mars kicking up debris containing cells that ultimately reaches Earth. Apparently, this is plausible. Even if it were true, it would only be passing the buck of spontaneous generation to Mars. There is still a need for at least one spontaneous generation event, where ever one wants it to be, to occur to explain life on Earth.
A theory has emerged lately about this early stage in life and during this time the ideas of Lamarck are far more relevant than those of Darwin.
Modern evolution of life
The problem with the tree of life
Before we can discuss this pre-Darwinian period of evolution, we must first discuss the Darwinian period of evolution. This would be the last couple million years. During this time the evolution has primarily occurred by Darwinian evolution or “vertical gene transfer” (see Fig. 1). Luckily, there are portions (i.e. genes) of the genetic code that are highly conserved (little difference between the human version and the bacterial version). This conservation allows common ancestry to be mapped out similarly to that in Fig. 2 but for all of life as opposed to just strains of a bacterium.
It was Carl Woese who led the effort to determine the relatedness of all life. His lab determined the sequence of stretches of those genes that encoded for the ribosomes (that central figure of life – so not surprisingly highly conserved) and then analyzed the differences to determine relatedness. A simple example of how this would work is in Fig. 4.
Figure 4. Using silent sequence changes to determine relationships.
Here, it is shown how changes in the sequence occur that do not change the function (represented as pronunciation) and how these changes can be used to map relatedness.
What Woese’s lab found was radically different from the previous ordering of life. Previous ordering of life was based on observable traits. This is the classic kingdom, phylum, class, order, family, genus, species system that was taught as lately as the mid-90s in high school biology. This ordering was effective for those close to humans but not for bacteria or archaea. With Woese’s tree based on genetic sequences, there emerged three primary domains: eukaryota, bacteria, and archaea. In comparison, previous trees seem myopic towards humans, perhaps not surprisingly.
What Woese’s lab found was radically different from the previous ordering of life. Previous ordering of life was based on observable traits. This is the classic kingdom, phylum, class, order, family, genus, species system that was taught as lately as the mid-90s in high school biology. This ordering was effective for those close to humans but not for bacteria or archaea. With Woese’s tree based on genetic sequences, there emerged three primary domains: eukaryota, bacteria, and archaea. In comparison, previous trees seem myopic towards humans, perhaps not surprisingly.
The myth of the universal common ancestor
Since this initial discovery sequencing has become increasingly easier and a mountain of additional data has been added to the analysis. Woese has discovered an interesting phenomenon with this new data. Many of the different data sets when examined independently result in radically different trees. While some argue that this is due to the quality of the data, Woese explains this as erosion of the tree from acquired evolution or “horizontal gene transfer” (see Fig. 3). This eliminates the possibility of a universal common ancestor (a single ancestor of all life). It also has led to greater appreciation of Lamarck’s original theory and has potentially opened up a new window to the beginning of life.
Early evolution of life
Woese’s theory of early life primarily involves horizontal gene transfer. Whereas today organisms have diverged enough where the genetic code is not readily transferred (it primarily occurs vertically – Fig. 1), during the early stages of life the genetic code would have been general enough and organisms would not have diverged enough so that the genetic code would have been readily transferred. This means that horizontal gene transfer (Fig. 3) would dominate evolution at this time. This can be thought of in the same way as the story of the tower of Babel. Early on everyone could share information (similar to horizontal gene transfer) due to sharing the same language, but as the dialects changed sharing information became more difficult.
The analogy works so well that one might propose that these battling forces of vertical and horizontal gene transfer may mirror the primary forces of human cultural evolution.
Tribal evolution of humanity
Genetic selection
One very interesting fact that few seem to realize is not many examples of positive selection (the popular idea of Darwinian evolution – Fig. 1) have been found in humans. The vast majority of those traits examined are found to have become popular by chance (remember the early comparison to the popularity of first names). What this means is that man is not evolving genetically as many believe. We’re just drifting.
Cultural selection
I propose that the only significant evolution that has occurred with man in the last, say, couple hundred thousand years has involved cultural evolution. This has primarily involved both a vertical transfer (traditions in culture) and horizontal transfer (cultural exchange).
Many may think politically incorrect thoughts at this moment. There is no need to be ashamed since many brilliant scientists have promoted the idea of eugenics. However, I will put forth two examples which prove the complete dominance of culture over genetics in mankind. The first is that mentioned by Gibbon in his “Decline and Fall of the Roman Empire” where he notices that the same population from the British Isles managed to produce cannibals and high literary minds over the course of just a thousand years. This is an incredibly short time in terms of genetic evolution especially given the long generation time for mankind.
The other example involves the close resemblance between medieval Europe and modern Africa. Again, the time that separates these two groups involves around 1500 years which is far smaller than even the rosiest analysis of European genetic evolution predicts. A recent study that supposedly showed the selection for a gene causing larger brains in Europeans was shot down in further analysis as being both neutral and not causing larger brains.
So culture is what matters not eugenics and all the horrors it spawns.
Modern evolution of humanity
Vertical transfer by traditions
Previously, I mentioned that the evolution of culture mirrors that of life. This was getting at how life was dominated by horizontal transfer early on and then vertical transfer later while I believe culture was dominated by vertical transfer early on and will be dominated by horizontal transfer as it progresses.
The most common and basic unit of human culture is the tribe. With the tribe traditions dominate while outside information is not readily received. There are many diverse examples of xenophobia throughout history. There is the high occurrence of suicide among Eskimos after exposure to modern Western culture. There is the story from medieval Germany where a well traveled son is rejected by his family due to him picking up mannerisms of other regions of what we now know as Germany.
All these show how the tribe is resistant to the horizontal transfer of information. However, modern technology is providing the means to erode these barriers and allow an unprecedented level of horizontal transfer.
‘Lamarkian’ evolution of societies
The primary barrier with information transfer in both biological systems and cultural systems is that of language. As both biotechnology and information technology advance these barriers are being reduced though for different reasons. Biological systems can be forced through the meddling of humans to share genetic information. With more and more tools to edit sequences base by base, genetics is able to move genes between incompatible species with different languages (the basic "language" would be based on codon tables). With information technology, there seems to be no limit to the amount of horizontal transfer as compatibility and physical barriers are being completely removed.
[Edit: Looking for finished version or going to have to write this from memory.]
What can we learn from bacteria?
An end to eugenics
Conservation vs. mutation & conservatism vs. liberalism
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