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Problem

While the Modern Synthesis successfully showed us that variation is produced in our DNA, this biggest problem with the Modern Synthesis is that it failed to account for where useful variation comes from.  As a result,  the Modern Synthesis misleads many to thinking that science could not explain how life came to be.  Paradoxically, while growing mountains of data provide more evidence than ever to explain evolution, the old theory presented as the Modern Synthesis has at the same time lost it’s explanatory power.  Although many claim that religious fanatics are the reason that a growing number of  American continue to reject evolution (Newport, 2012.), the problem is more fundamental.  And while most biologists are well aware that the Modern Synthesis has changed over time, textbook and popular accounts of biological evolution are decades out of date.

Integral Model

The new integral model of biological evolution that I am suggesting includes and transcends Darwins theory and the Modern Synthesis, (See Evolution of Evolutionary Theory).  Molecular biology provides more evidence than ever confirming the fact of evolution.  These new discoveries build on Darwin’s theory and the Modern Synthesis to provide a much richer understanding of evolution.    Now we know that the causes of genetic variation are much more complex  and yet in ways simpler than scientists before the 1960s could ever have imagined.  Following are just a few of the major discoveries leading to this new understanding of evolution.

Discovery of Horizontal Gene Transfer, Jumping Genes,  Symbiosis, Gene Duplication, and Hybridization 

In 1928, Frederick Griffith discovered that genes could be transfered horizontally, from one strain of bacteria to a different strain.  Because Griffith’s experiments were famous for showing that DNA is the heritable material, the importance of horizontal gene transfer as a mechanism for evolution was overlooked for another 70 years. Since Griffith’s famous experiment, horizontal gene transfer has been well documented.  Horizontal gene transfer explains how bacteria evolve antibiotic resistance.  It also explains how new metabolic pathways arise for degrading human-created chemicals (McGowan, et al, 1996).  While Horizontal Gene Transfer was for many years a well known phenomenon,  it was made famous as an agent of evolution by Ford Doolittle’s 2000 Scientific American article entitled “Uprooting the Tree of Life.”

In the 1940s, Barbara McClintock discovered “transposons.”  Popularly known as “jumping genes” transposons are stretches of DNA that can move around the genome.  In 1982, McClinock was awarded the Nobel Prize for Physiology or Medicine for this important discovery.  McClintock also discovered that genes could be switched on or off by control elements, some of which were on transposons.

Since McClintock’s ground breaking work on transposons, hundreds of discoveries have shown how DNA moves around the genome, how chromosomes recombine, how genomes hybridize, and how transposons can move from one species to another distant species.  Since sequencing the human genome, we now know that at least 80% of the human genome is made up of various types of transposable elements.  Since the discovery of transposons, many other forms of mobile DNA have been discovered, such as retrotransposons, LINES, SINES, plasmids, phage.

In the late 1960s, endosymbiosis was discovered to play a huge role in evolution. Lynn Margulis showed that the organelles of eukaryotic organisms arose as a result of the merger of two completely different types of organisms.  One of the greatest discoveries in biology, this work showed that evolution happens not only as the result of mutation and natural selection, but as the result of cooperation on a grand scale.

Observing the importance of mobile DNA in creating the novelty necessary for evolution, Susumo Ohno wrote the book, Evolution by Gene Duplication in 1970.  This book synthesized observations showing that genes evolved by the duplication of preexisting genes.  The duplicates  were then subsequently modified to create an entirely new function.  One of the most famous example is the globin genes.  Some of these genes carry oxygen in red blood cells.

Mobile DNA

All of these new discoveries about how variation is created could be characterized by one phrase: Mobile DNA.  Transposons move DNA around the genome, chromosomes move DNA by recombining; plasmids, phage and viruses move DNA from cell to cell and from organism to organism and from species to species. Naked DNA can also move laterally from species to species.  There are so many ways that cells have evolved the ability to move DNA that we can now observe a variety of ways that cells engage in Natural Genetic Engineering.

Because of the many diverse discoveries of mobile DNA,  we know that “random mutations” offer only a partial (and limited) explanation for how variation is created.

Natural Genetic Engineering

“Genetic and epigenetic changes result from the actions of cell biochemical activities, not from accidents. This is a critical fundamental discovery of molecular genetics.”
~ James Shapiro

The latest addition to evolutionary theory is “Natural Genetic Engineering.”  The phrase Natural Genetic Engineering was coined by molecular biologist James Shapiro.  NGE refers to the idea that cells have evolved mechanisms to enhance their evolvability.    It turns out that useful variation is not as random as we once thought. And useful variation is certainly not always due to errors or damage.  Natural Genetic Engineering tells us that variation is produced by the cells.  For years, scientists have known about cells amazing ability to evolve new and useful genetic variation in response to environmental stimuli.  We see examples of this in immune response, in sexual recombination, in horizontal gene transfer, in epigenetically induced transposition.  DNA mobilization is not simply dut to random accidents.  DNA mobilization is a response to the environment.

The famous microbiologist Jacques Monod called this “Tinkering.”  Cells take what works, duplicate it, move it and tinker with it to create a new function.

NGE has been well studied in the immune system. Cells in the active immune system mobilize DNA to create novel antibodies to defend the body from invading antigens.  This is a great example of natural genetic engineering.

In addition to featuring “Natural Genetic Engineering,” James Shapiro is a pioneer in championing this new integral theory of evolution in his book, Evolution, a View from the 21st Century and in hisHuffington Post blog.

Now, thanks to the maturation of cell biology, molecular biology and genetics, scientists know how variation is created.  This variation is not due simply to random errors and damage.  The most important variation comes from whole stretches of DNA that are duplicated, mobilized, and subsequently modified via “random mutations.”  Unknown to the authors of the Modern Synthesis, Mobile DNA has transformed the theory of evolution.  Mobile DNA explains horizontal gene transfer and it explains how useful genetic variation is created.   Mobile DNA required that the theory of evolution be revised.  Today, that model is the Integral Model of Evolution.

Mobile DNA makes sense of so-called Irreducible Complexity.  Using gene duplication, cells can evolve exquisitely complex structures that could never possibly arise due to errors and damage to DNA.

Mobile DNA explains the phenomenon of Punctuated Equilibrium.  Since the 1970s, scientists have observed that species in the fossil record seemed to remain the same for millions of years, but then they would change more quickly than could be explained by random point mutations.    These rapid changes are easily explained by mobile DNA.

The vast amounts of non-coding DNA in the human genome was a huge surprise.  Again, this is explained by mobile DNA. Over 80% of the human genome is made up of mobile DNA.

Another surprise is how similar human genes are to other animals.  Some genes, like the oxytocin gene is identical in all mammals.  Yet this same gene it expressed in radically different ways.  Expression is controlled by genetic switches.  How did these switches evolve?   Mobile DNA.

Better Education

Without a more comprehensive and more sensible theory of evolution, there is little hope that evolution can ever be effectively taught or accepted in society.  Many students don’t buy the old model. This is not because they are stupid, religious or dogmatic.  It’s because the Modern Synthesis has too many holes, it makes too little sense, and it requires too much blind faith to accept.  Rather that seeing these people as ignorant, perhaps we need to applaud them for their ability trust their instincts and to demand the truth.

Evolutionary biologists have long known about mobile DNA, horizontal gene transfer and other new mechanisms of evolution.   It’s time evolutionists quit defending an out of date theory and instead share a new Integral Evolutionary theory with people craving to know the truth of where they come from.

For Further Exploration

Ames, Bruce (1979). “Identifying environmental chemicals causing mutations and cancer”. Science 204

Beadle George and Edward Tatum (1941). ”Genetic Control of Biochemical Reactions in Neurospora”. PNAS 27 (11): 499–506.

Doolittle, Ford, W. (February 2000). “Uprooting the Tree of Life”. Scientific American. 282(2): 72–7.

Jacob, François (1977). “Evolution and Tinkering.” Science, New Series, Vol. 196, No. 4295 , pp. 1161-1166

Margulis, Lynn (1970). Origin of Eukaryotic Cells. Yale Univ. Press

Margulis, Lynn (Sagan at the time) (1967). “On the origin of mitosing cells”. J Theor Bio. 14 (3): 255–274.

McGowan, Catherine, Roberta Fulthorpe, Alice Wright and James Tiedje (1998). “Evidence for Interspecies Gene Transfer in the Evolution of 2,4-Dichlorophenoxyacetic Acid Degraders.” Appl Environ Microbiol. 1998 October; 64(10): 4089–4092.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC106609/

Muller, Herman Joseph, (1946) ”For the discovery of the production of mutations by means of X-ray irradiation.” http://www.nobelprize.org/nobel_prizes/medicine/laureates/1946/muller.html?print=1

Newport, Frank (2012). “In U.S., 46% Hold Creationist View of Human Origins: Highly religious Americans most likely to believe in creationism  http://www.gallup.com/poll/155003/hold-creationist-view-human-origins.aspx

Olendzenski, Lorraine and J. Peter Gogarten (2009).  “Evolution of Genes and Organisms: The Tree/Web of Life in Light of Horizontal Gene Transfer” in Natural Genetic Engineering and Natural Genome Editing: Ann. N.Y. Acad. Sci. 1178: 137–145.

Ohno, Susumu (1970). Evolution by gene duplication. Springer Verlag.

Shapiro, James (2012). Huffington Post Blog, http://www.huffingtonpost.com/james-a-shapiro/

Shapiro, James (2011). Evolution: A View from the 21st Century. FT Press Science.

Woese, Carl (June 2004). “A New Biology for a New Century”. Microbiol. Mol. Biol. Rev. 68 (2): 173–86

As denizens of the Genomic Age, we can now begin to see how evolution actually happens. And, according to genome scientist Dr. Sikela, we now know that “gene duplication is the major mechanism underlying genome evolution.”  Furthermore, we can see the particular sections of DNA that have duplicated to make us human!

Last week, I joined around 50 Denverites over dinner and beer to listen to genome scientist, Dr. James Sikela,  discuss “What Genes Make us Human?” at the March Cafe Scientifique.

As professor in the Department of Biochemistry and Molecular Genetics at the University of Colorado School of Medicine, Dr. Sikela has made major contributions to the human genome project.  With this expertise, he is on the ground floor finding those genes that separate us from the chimps and other primates.

Dr. Sikela’s team has discovered a particular stretch (domain) of DNA that is found in large copy numbers in humans.  Because these domains are highly expressed in brain tissue, this “DUF 1220″ domain may be the underlying cause of human brain evolution. In humans, the DUF1220 domain has duplicated to some 272 copies, more than the 125 found in chimps and more than any other primate or animal.   Dr. Sikela’s data shows that this copy number increase correlates with increased brain size.  (Yet he also warns that correlation is not necessarily causation.)  No one knows the function of the DUF1220 or the exact roles of the genes it hops into.

While the function of the DUF1220 remains unknown, what is crystal clear is the importance of gene duplication in evolution.  The more that scientists know about DNA, the better they can understand how genetic variety is introduced.

Dr. Sikela noted that while the DUF1220 may be responsible for the greater cognitive powers of humans, these duplicated DUF1220 sequences come at a cost.  It turns out the many genetic diseases, such as autism, schizophrenia and macrocephaly may be the result of DUF1220 duplications. Depending on your point of view, you can see gene doublings as selfish errors (departures from the norm and potential agents of disease) or generous in allowing the human species to flourish in new habitats.

According to Dr. Sikela, comparing genomes has given us 3 billion more data points in support of evolution.  If anyone could possibly doubt the fact of evolution, genome science proves beyond ALL doubt that evolution is a fact.

Furthermore, in Sikela’s words, genome sequencing clearly shows that “gene duplication is the major mechanism underlying genome evolution.”  In the past,  scientists have focused on single nucleotide substitutions as a primary generator of novelty.  Now we know that gene duplication provides the redundancy that facilitates innovation.

We can now sequence and compare entire genomes for a fraction of the cost and time as compared to years past.  This allows us to compare our human genome with that of our closest relatives to see what changes in DNA gave rise to us.  Thanks to genomics, we now have a much better view of how genetic novelty is created, and thus, a much clearer understanding of how evolution acutally happens.

For More Information:

• Dr. Sikela’s talk at Cafe Scientifique: http://www.cafescicolorado.org/CafeSci2%20Sikela.htm
• “What Makes Us Different” by Michael D. Lemonick in TIME magazine: . 
• “Evolution of genetic and genomic features unique to the human lineage“ Majesta O’Bleness , Veronica B. Searles, Ajit Varki , Pascal Gagneux & James M. Sikela. 
• Genome structural variation in human and primate evolution. - Powerpoint Presentation

From the Heart of Creation to Your Vision of Home:

     Exploring PLACE through Western Science and Feng Shui

 

August 12-18 2013
Location: Ghost Ranch , Abique, New Mexico-http://ghostranch.org/

TIME TRACE: From the Heart of Creation to Your Vision of Home
Experience an expanded sense of Belonging– to this Universe, Earth and all life– through wisdom from western science, native traditions, and feng shui. You will be exposed to the latest findings of cosmology, geology and genetics, and ground these new understandings by participating in activities that bridge the realms of Left brain-Right brain, Native Ceremony-Feng Shui and Vision-Manifestation. We will immerse ourselves in Deep Time to experience the sacred in the land. Through the elegant visual tool of spiral timelines, and the profound teachings of Native Ceremony, we will recognize that “All Our Relations” includes the stars, as well as all rooted, swimming, winged and walking beings. We will create intentions for the future while we’re together, and then use the wisdom tradition of Feng Shui to ground these in our homes and communities.

Contact Ghost Ranch for registration-(877) 804-4678

This 3 hour workshop integrates the seemingly unrelated fields of Big History and Feng Shui into an experience that gives participants a grounded and expanded sense of Belonging — to this Universe, Earth, and to the Front Range of Colorado!  From this sense of belonging, participants learn how to apply the wisdom tradition of Feng Shui to manifest their visions for the future.  Big History gives us a sense of our place in time.  Feng Shui is the art of arranging one’s home or workplace to optimize well-being.   Understanding Big History while applying the principles of Feng Shui can  help you experience greater energy and joy.  

When: Saturday, March 23 from 1-4 pm

Where: Montview Blvd. Presbyterian Church in the Study Group Room

1980 Dahlia St in Denver

RSVP:  303 355 2141

Bring a friend!

For more information, contact Karen at:  303 355 2141.

Karen and Laurelyn will be presenting a week-long version of this course at GHOST RANCH, the Presbyterian Conference Center in Northern New Mexico, in mid-August.

Cells have evolved "tools" (like the red enzyme above ) to move DNA around. These tools slice novel DNA (in blue) into host DNA (black double helix.).

Natural Genetic Engineering “can be compared to erector sets, LEGOs, carpentry, architecture or computer programming,”  writes Molecular Biologist James Shapiro, in “What Natural Genetic Engineering Does and Does Not Mean,” 2013. 

Biological evolution requires variation and selection.  Yet how is variation introduced?  Until scientists gained a clearer picture from molecular genetics, it was assumed that all variation was the result of errors, damage and accidents in the DNA. Now, thanks to advances in understanding molecular genetics,  we know that much of the important variation is the result of what molecular biologist James Shapiro calls Natural Genetic Engineering, or NGE.

According to Shapiro, “NGE is shorthand to summarize all the biochemical mechanisms cells have to cut, splice, copy, polymerize and otherwise manipulate the structure of internal DNA molecules, transport DNA from one cell to another, or acquire DNA from the environment.”  In addition, cells have mechanisms to create totally novel sequences by polymerizing DNA without at template.  They also have the ability to  take RNA molecules and reverse transcribe them into DNA.

Like photosynthesis, multicellularity and others aspects of life, the mechanisms for Natural Genetic Engineering have evolved over time.  It’s kind of like the evolution of evolvability. NGE does not replace random mutations and selection. NGE adds to this. For around 2 billion years of life on Earth, life was single celled.  Then, the rate of diversification sped up.  Evolution was able to happen at a faster rate, due to the emergence of more efficient mechanism of Natural Genetic Engineering.  Creatures moved out of water to inhabit every niche of planet Earth. There was an explosion of complex, multicellular, and multi-tissued life forms.

“There is now ample evidence that gene duplication is the most important mechanism for generating new genes and new biochemical processes that have facilitated the evolution of complex organisms from primitive ones.” ~ W. H. Li in Molecular Evolution, 1997

While Shapiro coined the term “Natural Genetic Engineering,” the mechanisms of NGE have been known for years.   In fact, genetic engineers who create genetically modified organisms have borrowed the tools that cells use for their own natural genetic engineering.

So many cell mechanisms have evolved to promote “Natural Genetic Engineering, that there is not space here to begin discussing them all.  Shapiro has collected a list of many of these mechanisms.  In cells, many of these tools for natural genetic engineering are “enzymes.”  These enzymes are like tiny molecular tools that can cut, copy and paste DNA.  (The the suffix “-ase is used to indicate that a molecule is an enzyme.) These tools of genetic engineering includes such things as “transposases,” “recombinases,” “ligases,” “integrases,” and “reverse transcriptases.”

The most prolific tool of natural genetic engineering is the transposase.  Transposases are the most abundant and ubiquitous genes on earth (Aziz, Breitbart and Edwards, 2010). Transposases are enzymes that cut and paste DNA from place to place in the genome and between cells.  Transposons are abundant and ubiquitous. In humans, up to 70% of the genome is made of transposons!

Other tools of natural genetic engineering include: recombinases. ligases, helicases, telemerases, reverse trasnscriptases, methylases.  The whole complex system of sex evolved as a way to recombine DNA.  Recombinases recombine sections of DNA.  Ligases are enzymes that connect two pieces of DNA.  Reverse transcriptase is an enzyme that copies an RNA molecule into DNA. 

Where did systems of Natural Genetic Engineering come from?  They evolved.  Because DNA repair mechanisms are ubiquitous and necessary for replication, DNA repair mechanisms may have been the precursors to NGE (Shapiro, 2011).    This is how NGE is both the product of evolution and the cause of the evolution of the profound diversity of life we see on earth today. Without NGE, life would exist, but it would be limited to simple cells, probably lacking nuclei and lacking the ability to thrive in diverse environments.

References:

Aziz, R.K., M. Breitbart and R.A. Edwards (2010). Transposases are the most abundant, most ubiquitous genes in nature. Nucleic Acid Research 38(13): 4207-4217.

Shapiro, James, (2011). Evolution: A View from the 21st Century. 

Shapiro, James.  Molecular Mechanisms of Natural Genetic Engineering

Elemental Birthdays: How to bring Science into Every Party. 

Looking for a fun new way to explore the cosmos?  Scientists Heather and Jon Cleland-Host wrote this book to share their enthusiasm and ideas to help you celebrate birthdays in a fun way while learning about the building blocks of our universe.  Although they wrote this book for children’s birthday parties, they found that adults love new ways to celebrate their birthdays as well.   Teachers can also use this book to inspire students in the classroom.  

Check out their website: http://solstice-and-equinox.com/elementalbirthdays.html

Elemental Birthdays “has transformed our family birthdays from just another party with cake and ice cream to an elemental celebration of life. The elements have provided meaningful themes to the parties or flavored themes chosen by our children. To our delight, we found that the value of Elemental Birthdays went beyond our children. Non-scientist friends and relatives sometimes seek to know what their element is for their coming birthday. Everyone learns the elements in a fun and very memorable way. We hope that Elemental Birthdays brings into the lives of you and your children the appreciation and excitement about science that it has brought into our lives.” ~ Heather and Jon Cleland-Host, in
Elemental Birthdays

Yet what most students don’t realize is that the theory of evolution has evolved way beyond the Modern Synthesis.  Failure to recognize this new theory and the many new discoveries in support of it has caused a great deal of confusion among students and non-scientists.  This failure is part of the reason that more Americans than ever doubt that evolution even happens (Newport, 2012).

When people understand this new, more integrated theory of evolution, they will see that evolution makes more sense and is thus easier to embrace because of it’s greater power to explain the origins of the great diversity of life on Earth.

Since the Modern Synthesis, scientists have made profound discoveries.  They’ve discovered the double helix structure of DNA.  They have discovered  mobile DNA, transposons, symbiosis, horizontal gene transfer, regulatory elements, gene duplication, and chromosome rearrangements.   They have sequenced the human genome and hundreds of other genomes.   These new discoveries have changed the theory of evolution yet again.  I call this new theory the Integral Model of biological evolution because it integrates Darwin’s ideas with  major breakthroughs in biology over the past 50 years.

Here, I give a brief overview of how our understanding of evolution has radically changed over time.  I do this by presenting three major theories of evolution: 1) Darwin’s theory 2) the Modern Synthesis and 3) the Integral Model of evolution.  The following table summarizes these three theories of evolution.

Table 1. Evolution of Evolutionary Theory

Three theories of evolution have different models for Variation, Inheritance, Selection and Time.  Darwin’s theory is represented by the color green.  Information that informed the Modern Synthesis is highlighted in blue. Information that informs the “Integral Model” is highlighted in purple. 

To make sense of the confusion surrounding the theory of evolution, it helps students to know that the theory of evolution is itself evolving. The table above shows three different models of evolutionary theory.  The first is Darwin’s model as described in Origin of Species.  The second model (featured in most textbooks and popular web sites) is the Modern Synthesis, a model that combined mid 20th century genetics with Darwinian theory.  The most recent model I call the “Integral Model.” I discuss these three theories in more detail below.

Darwin’s Theory

Darwin's theory was captured by his sketch of a Tree of Life.

Since before Darwin’s time, people have wondered how life diversified into such a vast array of forms.     Most people think Darwin’s greatest contribution was “Natural Selection.”  While Natural Selection (co-discovered by Wallace)  was indeed a important contribution, Darwin’s greatest and most enduring accomplishment was to create a powerful  framework for understanding how species change over time.  Darwin suggested that descent with modification (what we today call evolution) involves several “laws.”  These include the law of variation, the law of inheritance, and the law of selection (what scientists today call “differential reproductive success”). Darwin also acknowledged that long periods of time were required.  Today, scientists use the acronym VIST to describe these necessary ingredients (Variation, Inheritance, Selection and Time) of evolution.  Over the years, many details of evolutionary theory have changed, but Darwin’s basic structure for how evolution works remains the same.

Darwin acknowledged that variation, inheritance, selection and time are important for evolution.  Yet because Darwin didn’t know about DNA, genomes or genetics, he knew nothing about how variation occurred and he knew nothing about horizontal inheritance.  Instead, he focused his attention on what he could observe, which was natural selection.  In his famous book On the Origin of Species, Darwin not only outlined the general laws of how species change over time, he also detailed the principles of natural selection.

Defining Terms

Before delving into the details of evolutionary theory, it is essential to define our terms. The phrase “Natural Selection” often causes confusion because it has two distinct meanings.  For some people, including Darwin, Natural Selection is one element of evolution (the other elements being Variation, Inheritance and Time.)  Today, many scientists use the term “differential reproductive success” as a more accurate description that includes natural selection and excludes the processes of variation. For other people, “Natural Selection” is synonymous with the entire theory of evolution and all the processes associated with it, including Variation, Inheritance, Selection, and Time.  Because the latter definition includes a reference to itself (natural selection), this circularity tends to confuse.  Also, since scientists (including Darwin) have shown that evolution can happen by natural means other than natural selection, (for example via random drift, via endosymbiosis or via hybridization)  it is confusing to equate evolution with natural selection.    Therefore, when I refer to natural selection, I mean the process that describes one type of differential reproductive success.

Modern Synthesis

This tree of life represents the Modern Synthesis. It does not show horizontal gene transfer.

While Darwin’s theory offered a reasonable explanation for how selection occurred,  he had little insight into another essential aspect of evolution, which is variation.  In the early 20th century, biologists were beginning to understand how variation occured.  Geneticists clearly saw how heritable material contributed to evolution.  In 1942, Julian Huxley wrote a book entitled Evolution, The Modern Synthesis.  This book summarized and gave a name to the work of hundreds of researchers who had been researching the mechanisms of variation.  The Modern Synthesis united the Laws of Selection with the Laws of Variation as they were known at the time.

By coincidence, the mechanisms of variation began to be elucidated in the Nuclear Age.  In the 1940s, as nuclear weapons and energy were being explored, scientists exposed flies, molds, bacteria and other organisms to radiation.

They observed that genetic changes happen as a result of exposure to radiation.  (Beadle and Tatum, 1941; Muller, 1946.) Later, the growing field of synthetic chemistry led scientists to discover that many chemicals could alter the structure of DNA, and hence introduce variation.  Variation by radiation and from certain chemicals produced random changes in the DNA.  These changes were called “mutations.”

The term “mutation” originally simply meant “change.” Over time, however, the meaning of “mutation” began to mutate.  Instead of simply meaning “change,” mutation also began to mean deleterious change or change due to error or damage.   For science geeks, mutation often evokes images of flies with legs sprouting from their heads.  In the popular imagination, mutation evokes images of Godzilla, a mythical monster created by radiation from nuclear bombs. (Godzilla was created by Japanese artists after the bombing of Hiroshima and Nagasaki.) According to the Collins Thesaurus of the English Language, the term “mutant” is synonymous with freak, monster, mutation, deviant, oddity, monstrosity, freak of nature.

The Modern Synthesis also added Random Drift as a mechanism for selection.  Sometimes, populations undergo changes in gene frequencies, not as a response to the environment, but simply by chance.

Since the Modern Synthesis, people have assumed that variations result from random accidents due to damage or replication errors.   In classes on evolution, professors show slides of nuclear bombs and chemical factories to illustrate the causes of variation.  For years, people assumed that these random errors were responsible for the variation that gives rise to the tremendous diversity of life.  Still others were perplexed as to how errors and damage could cause the tremendous variety of life on Earth.  Today, we know that these random errors are only a small part of the story of how useful variations come to be.  Thanks to huge breakthroughs in science, we now know that the most important mechanisms for creating variation are not due to random errors or damage.  Instead, molecular and cell biology have given us a much more interesting view of how variation is created.

Integral Model of Evolution

Ford Doolittle's Web of Life replaces the Tree of Life by showing horizontal gene transfer. This image illustrates the Integral Model of Evolution.

Since the Modern Synthesis, many new discoveries have shaken the idea that random errors and natural selection alone can explain the magnificent diversity of life on Earth.  By not accounting for where useful variation comes from,  the Modern Synthesis led some non-scientists to think that science could not explain how life came to be.  Paradoxically, while the data was more abundant than ever to explain evolution, the old theory presented as the Modern Synthesis lost it’s explanatory ability.   As a result, a growing number of Americans doubt that evolution explains human origins, according to 2012 Gallup Poll (Newport, 2012.) 

Click here for more information about the New Integral Theory of Biological Evolution.

For Further Exploration

Ames, Bruce (1979). “Identifying environmental chemicals causing mutations and cancer”. Science 204

Beadle George and Edward Tatum (1941). ”Genetic Control of Biochemical Reactions in Neurospora”. PNAS 27 (11): 499–506.

Doolittle, Ford, W. (February 2000). “Uprooting the Tree of Life”. Scientific American. 282(2): 72–7.

Jacob, François (1977). “Evolution and Tinkering.” Science, New Series, Vol. 196, No. 4295 , pp. 1161-1166

Margulis, Lynn (1970). Origin of Eukaryotic Cells. Yale Univ. Press

Margulis, Lynn (Sagan at the time) (1967). “On the origin of mitosing cells”. J Theor Bio. 14 (3): 255–274.

McGowan, Catherine, Roberta Fulthorpe, Alice Wright and James Tiedje (1998). “Evidence for Interspecies Gene Transfer in the Evolution of 2,4-Dichlorophenoxyacetic Acid Degraders.” Appl Environ Microbiol. 1998 October; 64(10): 4089–4092. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC106609/

Muller, Herman Joseph, (1946) ”For the discovery of the production of mutations by means of X-ray irradiation.” http://www.nobelprize.org/nobel_prizes/medicine/laureates/1946/muller.html?print=1

Newport, Frank (2012). “In U.S., 46% Hold Creationist View of Human Origins: Highly religious Americans most likely to believe in creationism  http://www.gallup.com/poll/155003/hold-creationist-view-human-origins.aspx

Olendzenski, Lorraine and J. Peter Gogarten (2009).  “Evolution of Genes and Organisms: The Tree/Web of Life in Light of Horizontal Gene Transfer” in Natural Genetic Engineering and Natural Genome Editing: Ann. N.Y. Acad. Sci. 1178: 137–145.

Ohno, Susumu (1970). Evolution by gene duplication. Springer Verlag.

Shapiro, James (2012). Huffington Post Blog, http://www.huffingtonpost.com/james-a-shapiro/

Shapiro, James (2011). Evolution: A View from the 21st Century. FT Press Science.

Woese, Carl (June 2004). “A New Biology for a New Century”. Microbiol. Mol. Biol. Rev. 68 (2): 173–86

Wow.  Costa Rica is an evolutionary biologist’s paradise.