Category Archives: Darwinism

Photo credit: Jakob Rosen via Unsplash.

The power of epigenetic processes over genes continues to be a big subject in biology. Epigenetic processes control which genes are translated and which are silenced, which concentrations of transcripts are required, and how molecular machines assemble at the right times and places to steer gene products to their operational destinations. If sheet music is an argument for design, how much more the organization that makes it come alive in a marching bands halftime show?

The p53 protein has long been called the guardian of the genome for its key role in tumor suppression. Now, some German researchers are calling it the guardian of the (epi)genome. News from theUniversity of Konstanztells how a research team led by Ivano Amelio took a painstaking look at how p53 works.

Cells and their DNA integrity are particularly at risk when they divide, as they duplicate their DNA in the process. Like in any other replication process, such as photocopying a document or copying a digital file, it is disastrous if the template moves or is changed while the copy is being made.For this reason, genes cannot be transcribed i.e. used as templates for proteins while the DNA is being copied, Amelio explains. If they are transcribed anyway, serious disruptions occur, which can lead to cancer-promoting mutations. The results from Amelio and his team, now appearing as the cover story in Cell Reports, show that p53 inactivation favours such copy-related damage. They found thatp53 normally acts by changing cell metabolism in a way that prevents activation of genome regions that should remain inactive. [Emphasis added.]

Their work found that p53 is an epigenetic regulator: it keeps genes silent that should not be translated during mitosis by locking them away in heterochromatin. Without this control, genes become accessible to translation machinery at the wrong time, such as during mitosis. This causes so much damage, they found, that it will drive cells into a state of genomic instability that favours and worsens cancer progression.

By unravelling this mechanism, we could demonstrate that there isa link between metabolism, epigenetic integrity and genomic stability.In addition, we provided evidence thatp53 represents the switch controlling the on/off statusof this protection systemin the response to environmental stress, Amelio summarizes the finding.

The question of how p53-inactivated tumours develop genomic instability has plagued the scientific community for quite some time. Now we have certainty that, in these tumours, there is a problem at the metabolic level that is reflected in the integrity of the epigenome.Hence, p53 should actually be called guardian of the (epi-)genome.

TheJohn Innes Centre in the UKannounced the solution to an enigma: how plants compact their DNA in sperm cells. Animals, which have swimming sperm cells, do it by replacing their histones with protamines. But plants, which spread their gametes via pollen, maintain their histone-based chromatin through fertilization. Why the difference, and how do plants compact the DNA in the male gametes?

The answer was found by a research team at the Centre led by Professor Xiaoqi Feng. It involves condensates (see myarticle on the Caltech study) that form by phase separation, intrinsically disordered regions of certain proteins, and epigenetics. Professor Fengs research team used super-resolution microscopy, comparative proteomics, single-cell-type epigenomic sequencing and 3D genome mapping to investigate this mystery. Key to the solution was identification of a histone variant named H2B.8. It is specifically expressed in sperm nuclei.

H2B.8 has a longintrinsically disordered region (IDR), a feature that frequently allows proteins to undergophase separation. The research found nearly all flowering plant species have H2B.8 homologs (copies), all of which contain an IDR, suggesting important functions.

So why do plants need DNA compaction, when the sperm dont need to swim to the egg? Pollen grains land on a pistil and send long pollen tubes to reach the eggs. Compaction of the sperm cells, therefore, serve a purpose for angiosperms. Interestingly, gymnosperms, which use a different method of pollination, do not compact their sperm genomes, and lack H2B.8.

Dr Toby Buttress first author of the study said: We propose that H2B.8 isa flowering plant evolutionary innovationthat achievesa moderate level of nuclear condensationcompared to protamines, which sacrifice transcription for super compaction.H2B.8-mediated condensation is sufficient for immotile spermand compatible with gene activity.

A lively follow-up to Caltechs findings last year about condensates was published byNature, The shape-shifting blobs that shook up cell biology. Reporter Elie Dolgin calls these membraneless organelles droplets, condensates, and granules. She uses the same office floor plan metaphor that Caltech used:

For years, if you asked a scientist how they pictured the inner workings of a cell, they might have spoken ofa highly organized factory, with different departments each performing specialized tasks in delineated assembly lines.

Ask now, and they might be more inclined to compare the cell to a chaotic open-plan office, withhot-desking zoneswhere different types of cellular mattergatherto complete a task andthen scatterto other regions.

The picture is less one of robots anchored to the floor on an assembly line, and more one of intelligent actors gathering on the fly, interacting, sharing materials, and solving problems. Isnt that just like squishy biology anyway? Cells seem like chaotic blobs at one level, but they somehow give rise to a flying owl, a leaping dolphin, and a mathematician at a chalkboard. Clearly things are working at levels of engineering beyond our current ability to fathom.

We have the observations that condensates form, says Jonathon Ditlev, a cellular biophysicist at the Hospital for Sick Children in Toronto, Canada. Now we need to show why they are important.

Dolgin relates how these blobs self-organize through phase separation, but many questions remain. How do the right ingredients get into these molecular crucibles that speed up interactions by orders of magnitude? How do they separate when the work is done? He doesnt mention epigenetics in his article, but the implication is clear that genetics alone cannot explain this.

Whether plant DNA compaction can be called an evolutionary innovation as opposed to a designed solution can be debated. Regarding that controversy, atThe Scientist, Katarina Zimmer asks, Do Epigenetic Changes Influence Evolution?

Evidence is mounting thatepigenetic marks on DNA can influence future generationsin a variety of ways. Buthow such phenomena might affect large-scale evolutionary processes is hotly debated.

After telling about a case where nematodes inherited a stress response, Zimmer delves into the current fierce debate between believers and doubters about whether epigenetics requires revisions to evolutionary theory.

No one doubts the examples of epigenetic inheritance, but some in the old guard consign them to minor roles in long-term evolution. Zimmer mentions the buzz generated by thearticle byStephen Buranyi atThe Guardianasking, Do we need a new theory of evolution? (seeDavid Klinghoffers analysis here). One of the revisionists Zimmer quotes is Alyson Ashe at the University of Sydney, who also observed epigenetic inheritance inC. elegans.

Specifically, the Modern Synthesis developed in the 1940ssupposes that evolution is driven solely by random DNA mutations. While many scientists question whether non-DNA-based mechanisms could be meaningful contributors to evolutionary processes,some say that textbooks are due for an update.

We dont need to rewrite and throw away the current theories,but theyre incomplete, says Ashe.They need adjustment to show how epigenetics can interplay with those theories.

Zimmer leaves the controversy unresolved, but its likely that Darwinians will have to face the epigenetic music soon as its drumbeat gets louder. If the instrumentalists are like the genes, other entities must be telling the band members what music to play, when to start, and how to scatter and gather into the next formation on the field, or else there would be cacophony. If neo-Darwinism cannot even get random notes on a page to result in a melody, how can it account for a drum major, manager, librarian, programmer, drill team and all the other entities needed for a coherent performance? Thanks to epigenetics, all the players condense in the right positions, move around while playing, and give a crowd-pleasing performance of Strike Up the Band.

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Epigenetics Directs Genetics And Thats a Problem for Darwinism

Top Questions

How was Herbert Spencer educated?

What did Herbert Spencer do for a living?

Herbert Spencer worked briefly as a schoolteacher and was later employed as a railway engineer (183741) and as a writer and subeditor (copy editor) for The Economist (185153). He resigned his position with The Economist after receiving an inheritance from his uncle.

What did Herbert Spencer write?

Herbert Spencers major writings included The Proper Sphere of Government (1843), Social Statics (1851), Education: Intellectual, Moral, and Physical(1861), and The Synthetic Philosophy, a multivolume work ranging over psychology, biology, sociology, and ethics and published between 1855 and 1896.

Why is Herbert Spencer famous?

Herbert Spencer is famous for his doctrine of social Darwinism, which asserted that the principles of evolution, includingnatural selection, apply to human societies, social classes, and individuals as well as to biological species developing over geologic time. He is also remembered for introducing the term survival of the fittest.

Summary

Herbert Spencer, (born April 27, 1820, Derby, Derbyshire, Englanddied December 8, 1903, Brighton, Sussex), English sociologist and philosopher, an early advocate of the theory of evolution, who achieved an influential synthesis of knowledge, advocating the preeminence of the individual over society and of science over religion. His magnum opus, The Synthetic Philosophy (1896), was a comprehensive work containing volumes on the principles of biology, psychology, morality, and sociology. He is best remembered for his doctrine of social Darwinism, according to which the principles of evolution, including natural selection, apply to human societies, social classes, and individuals as well as to biological species developing over geologic time. In Spencers day social Darwinism was invoked to justify laissez-faire economics and the minimal state, which were thought to best promote unfettered competition between individuals and the gradual improvement of society through the survival of the fittest, a term that Spencer himself introduced.

Spencers father, William George Spencer, was a schoolmaster, and his parents dissenting religious convictions inspired in him a nonconformity that continued active even after he had abandoned the Christian faith. Spencer declined an offer from his uncle, the Reverend Thomas Spencer, to send him to the University of Cambridge, and in consequence his higher education was largely the result of his own reading, which was chiefly in the natural sciences. He was, for a few months, a schoolteacher and from 1837 to 1841 a railway civil engineer.

In 1842 he contributed some letters (republished later as a pamphlet, The Proper Sphere of Government [1843]) to The Nonconformist, in which he argued that it is the business of governments to uphold natural rights and that they do more harm than good when they go beyond that. After some association with progressive journalism through such papers as The Zoist (devoted to mesmerism, or hypnosis, and phrenology) and The Pilot (the organ of the Complete Suffrage Union), Spencer became in 1848 a subeditor of The Economist. In 1851 he published Social Statics, which contained in embryo most of his later views, including his argument in favour of an extreme form of economic and social laissez-faire. About 1850 Spencer became acquainted with the novelist George Eliot, and his philosophical conversations with her led some of their friends to expect that they would marry, but in his Autobiography (1904) Spencer denies any such desire, much as he admired Eliots intellectual powers. Other friends were the writer George Henry Lewes, the biologist Thomas Henry Huxley, and the philosopher and economist John Stuart Mill. In 1853 Spencer, having received a legacy from his uncle, resigned his position with The Economist.

Spencer published the first part of The Principles of Psychology in 1855. Between 1854 and 1859 he published a series of essays on education, which were collected in Education: Intellectual, Moral, and Physical (1861). Spencer rejected some traditional elements of the curriculum and emphasized the importance of self-development, sympathetic attention from instructors, observation and problem solving, physical exercise and free play, and discipline derived from experiencing the natural consequences of ones actions rather than from punishments imposed by teachers and parents. Education was eventually adopted as a textbook in nearly all teacher-training colleges in England. In 1860 Spencer issued a prospectus and accepted subscriptions for a comprehensive work, The Synthetic Philosophy, which was to include, besides the already-published Principles of Psychology, volumes on first principles and on biology, sociology, and morality. First Principles was published in 1862, and between then and 1896, when the third volume of The Principles of Sociology appeared, the task was completed. In order to prepare the ground for The Principles of Sociology, Spencer started in 1873 a series of works called Descriptive Sociology, in which information was provided about the social institutions of various societies, both primitive and civilized. The series was interrupted in 1881 because of a lack of public support. Spencer was a friend and adviser of the social reformer Beatrice Potter, later Beatrice Webb, who frequently visited Spencer during his last illness and left a sympathetic and sad record of his last years in My Apprenticeship (1926). Spencer died in 1903, at Brighton, leaving a will by which trustees were set up to complete the publication of the Descriptive Sociology. The series comprised 19 parts (18731934).

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Spencer was one of the most-argumentative and most-discussed English thinkers of the Victorian era. His strongly scientific orientation led him to urge the importance of examining social phenomena in a scientific way. He believed that all aspects of his thought formed a coherent and closely ordered system. Science and philosophy, he held, gave support to and enhanced individualism and progress. Although it is natural to cite him as the great exponent of Victorian optimism, it is notable that he was by no means unaffected by the pessimism that from time to time clouded the Victorian confidence. Evolution, he taught, would be followed by dissolution, and individualism would come into its own only after an era of socialism and war.

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Herbert Spencer | Biography, Social Darwinism, Survival of the Fittest ...

Herbert Spencer (1820-1903)

On April 27, 1820, English philosopher, biologist, anthropologist, sociologist, and prominent classical liberal political theorist of the Victorian era Herbert Spencer was born. Spencer is best known for the expression survival of the fittest, which he coined in Principles of Biology (1864), after reading Charles Darwins On the Origin of Species.[4] This term strongly suggests natural selection, yet as Spencer extended evolution into realms of sociology and ethics, he also made use of Lamarckism.[5] Spencer developed an all-embracing conception of evolution as the progressive development of the physical world, biological organisms, the human mind, and human culture and societies. During his lifetime he achieved tremendous authority, mainly in English-speaking academia.

The truth is, that those who have never entered upon scientific pursuits know not a tithe of the poetry by which they are surrounded. Herbert Spencer, Lectures on Education delivered at the Royal Institution of Great Britain, London, 1855

Spencer was born in Derby, England, the son of William George Spencer (generally called George), a religious dissenter. Herbert Spencer was educated partly by his father and partly by members of the Derby Philosophical Society who introduced him to pre-Darwinian concepts of biological evolution. Reverend Thomas Spencer, Herbert Spencers uncle, then completed Spencers limited formal education by teaching him some mathematics and physics, and enough Latin to enable him to translate some easy texts.

Spencer was known to work quite interdisciplinary, being occupied as a civil engineer during the 1830s as well as writing for provincial journals. About a decade later, Spencer served as sub-editor on the free-trade journal The Economist, during which time he published his first book, Social Statics (1851), which predicted that humanity would eventually become completely adapted to the requirements of living in society with the consequential withering away of the state. Spencer met influential characters including John Stuart Mill, Harriet Martineau, George Henry Lewes and Mary Ann Evans. His friendship with Evans and Lewes resulted in his second book, Principles of Psychology. It was founded on the assumption that the human mind was subject to natural laws and that these could be discovered within the framework of general biology.[6]

All evil results from the non-adaptation of constitution to conditions. This is true of everything that lives. Herbert Spencer, Social Statistics (1851)

In 1858, Herbert Spencer produced an outline of what was to become the System of Synthetic Philosophy. He intended to demonstrate that the principle of evolution applied in biology, psychology, sociology and morality.Around 1860 Spencer began his lifes work: the synthesis of all human knowledge, related to an omnipresent principle that works in all living things: evolution. According to Spencer, only the laws of evolution allow the structuring and integration of empirical data from all physical, social and psychological fields of science under one principle; therefore evolutionism represents the first scientifically founded world view. As an enthusiastic supporter of Darwinism, he believed he could apply the principle of evolution in all sciences and thus unite them into a system of synthetic philosophy. Spencer was convinced that she had found an important key to her understanding in the self-organizing genesis of things. The starting point that things in the world develop without divine (or other) control and that something more complex or higher emerges from simplicity was revolutionary for his time.

If a single cell, under appropriate conditions, becomes a man in the space of a few years, there can surely be no difficulty in understanding how, under appropriate conditions, a cell may, in the course of untold millions of years, give origin to the human race. Herbert Spencer, Principles of Biology (1864)

Many people know Herbert Spencer best for his theory on Social Darwinism. It applies the law of survival of the fittest to society. This means that humanitarian impulses had to be resisted as nothing should be allowed to interfere with natures laws, including the social struggle for existence. In biology, the competition of various organisms can result in the death of a species or organism. Spencer advocated this kind of competition to be closer to the one used by economists, where competing individuals or firms improve the well being of the rest of society.According to Spencer, social development is similar to that of a biological organism. Controlled by the invisible hand of evolution, that which best contributes to the survival of the organism prevails in the long term. In this process, the unadapted, i.e. the socially weaker, stands in the way of societys progress.

Finally, Spencer developed a general philosophy in his further principles, based on the various previously developed theories of evolution: the entire universe functions like a gigantic organism, which leads with time to an increasingly harmonious coordination of the individual components. Like Comte before, Spencer found the same development not only for the whole, but within each component.

In 1902, shortly before his death, Spencer was nominated for the Nobel Prize for literature. Politically, Spencer was firmly rooted in classical liberalism, which was reflected above all in his late work. Spencer tried to unite all the knowledge of his time in a system of synthetic philosophy. Unlike later Social Darwinists, Spencer was firmly rooted in liberalism. Based on his Protestant ethics, he postulated the Law of Equal Freedom (LEF) that a person has all freedom as long as he does not interfere with the freedom of another. Both for these ethical reasons and because they contradicted the logic of evolution, Spencer rejected any intervention of the state in human society. In his most political work, The Man Versus the State, he consistently went so far as to demand the right of every individual to secession from the state. He continued writing all his life, in later years often by dictation, until he succumbed to poor health in 1903 at the age of 83.

Ethical Theory of Herbert Spencer, [12]

References and Further Reading:

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Herbert Spencer and Social Darwinism - SciHi BlogSciHi Blog

October 10, 2022 | David F. Coppedge

Regulating existing genetic information is a way lifegains heritable change without blind natural selection

What if much of the alleged evidence for evolutionary adaptation is not Darwinian?

The fit of organisms to their environment, called adaptation, has fascinated biologists since ancient times. To Charles Darwin, it became a fundamental part of his theory of natural selection. Darwinian theory, and then later Neo-Darwinism (which attributed variability to random mutations) pictured the environment as a driver of adaptation. Theres another way of understanding the fit of organisms to their environment, however, that ascribes adaptation to intelligent causes. That way is the newer science of epigenetics, in which internal factors tune the genome to its surroundings quickly, without waiting for some beneficial random mutation to show up.

One Sequence, Many Variations (The Scientist, 5 Oct 2022). At the Van Andel Institute, researchers have a new take on what makes animals and plants adapt to their environment. Its called epigenetics, above the genes. Andrew Pospisilik is a founding member of the VAIs Metabolic and Nutritional Programming group. Pospisilik explores the epigenetic changes that give organisms the plasticity to change in response to their environments.

Is this a big change in thinking?

For years, scientists have been fascinated with how DNA mutations impart phenotypic changes. However, epigeneticists including Andrew Pospisilik think mutations are responsible for only a portion of the variation present in all organisms. Epigenetic changes from molecules attaching to DNA and histonesproteins that compact DNA into chromatinand other factors that modulate gene expression allow organisms the flexibility to change according to their environment. These changes can be inherited, altering the phenotypes of future generations in the absence of mutations.

DNA is tightly wound around chromatin, affecting access to genes by transcription factors and polymerases. (Credit: Illustra Media)

To the extent this happens, it represents a very different picture from classic Neo-Darwinism. Neo-Darwinism places all phenotypic change in random mutationsmistakes in the genes, whether from cosmic rays, copying errors or other undirected sourcesand claims that only those that are mildly beneficial will be inherited, while the vast majority are deleterious or neutral.

But if Pospisilik is right, organisms can get many variations from one sequence, applying epigenetic factors built into the cells internal operations (e.g., regulatory elements). He explains why the study of epigenetics is important:

Ever since scientists discovered DNA, figured out what genes were, and started making mutations and sequencing genes, they saw how reproducible the consequences of strong mutations were and got lost in the default notion that everything must be genetics. As scientists map all the genetic differences between humans, we are finding that we are on course to understand, at most, one-third of the puzzle.

Mutations cannot tell the whole story, he continues. For example, identical twins are not always identical.

The missing piece is developmental plasticity, which is a major determinant of who and what we are. In organisms that originate from the same DNA template, factors have evolved to compress their variability and mediate their plasticity.

Whether these factors have evolved in a Darwinian sense, they are not external, but internal to the organism. They exist within the epigenome to give flexibility to organisms placed in new environments. His claim that factors have evolved to compress their variability might be a holdover from decades of Neo-Darwinian dogma. It is just as possible to assert that epigenetic factors were built into the organism from the start. If variations are resulting from within the organism, they are not the consequence of mutations.

A designing intelligence, for instance, might pre-program variability for robustness, similar to how the immune system generates millions of antibodies in a targeted search for an antigen. A targeted search for a match is different from a random search (or blind search), because the outcome has been specified beforehand. This implies the pre-existence of information that specifies the target and recognizes a successful outcome. The environment, oblivious as it is to an organisms needs, cannot be the source of information.

Usually, we think that DNA mutations drive this, but epigenetics allows the same DNA template to generate additional outcomes. For organisms that produce many offspring, such as fruit flies, it does not make evolutionary sense to have hundreds of truly identical offspring. If their DNA sequence makes them sensitive to an environmental perturbation, then they could all die. It is best to have variability in that system so that some of them can live.

Histone tags on chromatin constitute a code separate from DNA. This histone code is one method cells regulate gene transcription and alternative splicing, yielding many variations from one sequence.

Variability in that system sounds like something that requires foresight. A designer of programmed robots, for instance, might build in modules that drive variability such that some of the products would flourish in a given situation. This would be very different from traditional Neo-Darwinism, where the environment is thought to drive adaptation via random mutations.

Pospisilik gives examples of how the same genome can generate completely different phenotypes, depending on the epigenetic regulatory factors. One dramatic example is honeybees: from the same genome, the hive produces a queen, workers, drones and other members of the caste system. What if varieties of bee, wasp, termite and ant colonies had adapted differently based on epigenetic factors? This could explain why similar species within a family have caste systems and others do not, and why the caste systems are highly organized and successful.

Sometimes epigenetically-driven phenotypic plasticity can go awry. He gives an example:

In humans, the Dutch Hunger Winter is a famous example. It was a prolonged famine period during the Second World War. Scientists have found that offspring of people who lived through that period are more susceptible to cardiometabolic diseases a half-century later. Like the queen bee example, these seem to be direct early consequences of the fetus being reprogrammed.

In the remainder of the interview, Andrew Pospisilik shares ideas about how knowledge of epigenetics can help treat diseases like cancer. Based on his experience to this point, he thinks that

Epigenetics is probably one-third of the puzzle that causes a persons specific disease, but is relatively understudied. Understanding this black-box is important; it could open the door to new epigenetic therapies. By enabling precision diagnosis, we will know why one person with type 2 diabetes will respond to one medication but the next person might not. Also, because many epigenetic processes are believed to be generated very early in life, scientists could measure biomarkers at birth to see what epigenetic risk a person has for a disease.

With his colleague Peter Jones, Pospisilik shares his opinion that the Van Andel Institute has a world-class, forward-thinking faculty and scientific cores who are most interested in publishing great science. Will the great science of the 21st century abandon Neo-Darwinism and focus on epigenetics?

This article is exciting because it appears to support ICRs current research program on Continuous Environmental Tracking (CET) as a model for adaptation (see this lead article from ICR with links to detailed explanations). Epigenetic matching of the genome to environmental constraints is very different from Neo-Darwinism, because it locates adaptation internally instead of externally. ICRs engineering-based biological model rids biology of the mystical notion of a personified natural Selector that picks winners and losers by chance, and puts the design into the foresight and programming skill of the designing intelligence.

This is a good introduction into the significance of epigenetics.

Another advocate of epigenetics as a purpose-driven alternative to Darwinism is Dr Thomas Woodward, founder of the C.S. Lewis Society at Trinity College of Tampa, Florida. His book with Dr James P Gills, The Mysterious Epigenome: What Lies Beyond DNA (2011) introduced readers to the factors that tune the genome for the organisms health and success. This new article at The Scientist by secular geneticists supports the contention of the book that epigenomics would overtake genomics as a flourishing avenue toward understanding biology in the coming years.

No one yet knows the extent to which epigenetics can account for adaptation. I suspect, though, that this engineering-based approach to phenotypic plasticity and variability within species up to the family taxonomic level will prove fruitful, much more so than the current reliance on the Stuff Happens Law of natural selection, which relies on sheer dumb luck.

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Epigenetics: Adaptation Without Darwinism CEH

Photo: Galpagos marine iguana, by Datune at English Wikipedia, Public domain, via Wikimedia Commons.

Editors note:We are delighted to present a new series by biologist Jonathan Wells asking, Is Darwinism a Theory in Crisis? This is the first post in the series, which is adapted from the recent book,The Comprehensive Guide to Science and Faith.Find the full series here.

What does it mean to say that a theory is in crisis? Its not enough to point out that a theory is inconsistent with evidence. Critics have been pointing out for decades that Darwinism doesnt fit the evidence from nature. Biologist Michael Denton publishedEvolution: A Theory is Crisis in1986.1Thirty years later, he drove the point home withEvolution: Still a Theory in Crisis.2

But Darwinism is still with us, for two reasons. First, Darwinism is not just a scientific hypothesis about specific phenomena in nature, like Newtons theory that the gravitational force between two bodies is inversely proportional to the square of the distance between them (17th century), Lavoisiers theory that things burn by combining with oxygen (18th century), or Maxwells theory that light is an electromagnetic wave (19th century). Darwin calledOn the Origin of Speciesone long argument, and a central part of it was atheologicalargument against the idea that species were specially created.3

Second, established scientific research programs such as Darwinism are never abandoned just because of some problems with the evidence. The idea that all species are descendants of one or a few common ancestors that have been modified by mutation and natural selection will maintain its dominance until large numbers of scientists embrace a competing idea. Currently, the major competing idea is intelligent design (ID), which maintains (contra Darwin) that some features of living things are better explained by an intelligent cause than by unguided natural processes. The shift, if and when it happens, will be a major scientific revolution. One way to approach this phenomenon is through philosopher of science Thomas Kuhns 1962 bookThe Structure of Scientific Revolutions.4

I will begin by summarizing some of Kuhns key insights. I will then apply those insights to the present conflict between Darwinism and intelligent design. As I do so, I point out some problematic aspects of Kuhns work, but I conclude that recent events fully justify calling Darwinism a theory in crisis.

According to Kuhn, normal science is research firmly based upon one or more past scientific achievements, achievements that some particular scientific community acknowledges for a time as supplying the foundation for its further practice. Those achievements were sufficiently unprecedented to attract an enduring group of adherents away from competing modes of scientific activity. They were also sufficiently open-ended to leave all sorts of problems to be solved. Kuhn called achievements that share these two characteristics paradigms.5

Once a paradigm becomes dominant, the normal practice of science is simply to solve problems within that paradigm. In the process, an institutional constellation forms that includes the formation of specialized journals, the foundation of specialist societies, and the claim for a special place in the curriculum.6The last is very important, because one characteristic of the professional scientific community [is] the nature of its educational initiation. In the contemporary natural sciencesthe student relies mainly on textbooks until the third or fourth year of graduate work, at which point the student begins to do independent research. It is a narrow and rigid education, probably more so than any other except perhaps in orthodox theology.7

Kuhn wrote,

No part of the aim of normal science is to call forth new sorts of phenomena; indeed, those that will not fit the box are often not seen at all. Nor do scientists normally aim to invent new theories, and they are often intolerant of those invented by others.8

Yet no paradigm that provides a basis for scientific research ever completely resolves all its problems. When anomalous evidence emerges, however, scientists first line of defense is usually to devise numerous articulations andad hoc modifications of their theory in order to eliminate any apparent conflict. They never simply renounce the paradigm unless another is available to take its place. Thus the decision to reject one paradigm is always simultaneously the decision to accept another, and the judgment leading to that decision involves the comparison of both paradigms with natureandwith each other.9

The most effective claim that proponents of a new paradigm can make is that they can solve the problems that have led the old one to a crisis.10Even then, Kuhn wrote,

The defenders of traditional theory and procedure can almost always point to problems that its new rival has not solved but that for their view are no problems at allInstead, the issue is which paradigm should in the future guide research on problems many of which neither competitor can yet claim to resolve completely. A decision between alternate ways of practicing science is called for, and in the circumstances that decision must be based less on past achievement than on future promise.11

How does a new paradigm originate? Kuhn wrote,

Any new interpretation of nature, whether a discovery or a theory, emerges first in the mind of one or a few individuals. It is they who first learn to see science and the world differently, and their ability to make the transition is facilitated by two circumstances that are not common to most other members of their profession.12

First, Kuhn wrote, their attention has been concentrated upon the crisis-provoking problems. Second, these individuals are usually so young or so new to the crisis-ridden field that practice has committed them less deeply than most of their contemporaries to the world view and rules determined by the old paradigm.13

According to Kuhn,

Paradigms differ in more than substance, for they are directed not only to nature but also back upon the science that produced them. They are the source of the methods, problem-field, and standards of solution accepted by any mature scientific community at any given time. As a result, the reception of a new paradigm often necessitates a redefinition of the corresponding science.14

Next, Theory in Crisis? Redefining Science.

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Is Darwinism a Theory in Crisis? | Evolution News

Definition of Social Darwinism

Social Darwinism is the conflict between social groups which results in the most socially capable or fit group coming out on top as the winner, usually in terms of influence and wealth. According to social Darwinism, rich people would succeed and poor people would fail.

So where does social Darwinism come from? Remember Charles Darwin and his laws of natural selection and survival of the fittest? Let's briefly review these concepts before linking Charles Darwin to social Darwinism.

Natural selection happens over time, when certain characteristics disappear because a species has no use for them, other characteristics prevail. For example, evolutionists believe that ducks developed webbed feet over time so that they could swim faster. This means that the ducks without webbed feet eventually died off. This could be because their non-webbed feet didn't allow them to swim fast enough to escape their hunters. The ones that escaped reproduced and gave birth to more ducks with webbed feet.

Another example is pesticide-resistant insects - when treated with pesticide, insects are supposed to die. Some live due to genetic modifications and reproduce, creating more pesticide-resistant offspring.

Survival of the fittest refers to the most adaptable species being able to live and reproduce. The ducks that swam faster survived, as well as the insects that were resistant to pesticide. They reproduce and create more offspring who have similar genes so that they are able to survive as well. According to this theory, over time, only the fit survive.

Because of the name, many people think that Charles Darwin came up with the idea of social Darwinism. This is not the case. Herbert Spencer, Walter Bagehot, and William Graham Sumner thought that the ideas of natural selection and survival of the fittest applied to people as well, especially people living under laissez-faire capitalism.

Laissez-faire capitalism exists when the government does not interfere with business or personal affairs. Spencer, Bagehot, and Sumner supported the idea that without government assistance, only the socially fit would survive. This, again, meant that those with money and assets would survive and those with nothing would not.

Over time, social Darwinism was criticized because of its applicability and comparisons to extreme nationalism, imperialism, and Nazism.

Nationalism is when residents of one country feel that their country and way of life are superior over other countries. Social Darwinists would support trying to convert or change others to follow their way of life because they believe it is better - an example is forced religious conversions.

Imperialism is when one country's military attempts to take over another country. Social Darwinists would support the English colonialists taking over the land of the Native Americans.

Social Darwinist examples from Nazi Germany include things like:

Ads promoting discrimination towards the mentally disabled - these ads told people that mentally disabled people were costing others lots of money. Publications like these promoted the mistreatment of the mentally challenged population. Social Darwinists may say that this type of conflict is supposed to happen in order to determine who will live on.

Another example of Nazi Germany was killing and mistreating Jewish people. Nazis believed the Aryan race was superior to all, but especially to the Jewish people. Jewish people were viewed was inferior and undesirable. In order to make sure that their undesirable traits were not passed on, they attempted to kill them all.

Social Darwinism has lost a lot of support due to people gaining an understanding of social issues and acceptance. Discrepancies among social classes still exist, but the extreme beliefs of social Darwinism have dissolved.

Social Darwinism is the conflict between social groups which results in the most socially capable or fit group coming out on top as the winner, usually in terms of influence and wealth. Natural selection happens over time, when characteristics disappear because a species has no use for them, other characteristics prevail. Survival of the fittest refers to the most adaptable species being able to live and reproduce.

Herbert Spencer, Walter Bagehot, and William Graham Sumner thought that the ideas of natural selection and survival of the fittest applied to people as well, especially people living under laissez-faire capitalism. Laissez-faire capitalism exists when the government does not interfere with business or personal affairs. Over time, social Darwinism was criticized because of its applicability and comparisons to extreme nationalism, imperialism and Nazism.

Nationalism is when residents of one country feel that their country and way of life are superior over other countries. Imperialism is when one country's military attempts to take over another country.

Go here to read the rest:

Social Darwinism | Examples & History - Study.com

Phrase to describe the mechanism of natural selection

"Survival of the fittest"[1] is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. The biological concept of fitness is defined as reproductive success. In Darwinian terms, the phrase is best understood as "Survival of the form that will leave the most copies of itself in successive generations."

Herbert Spencer first used the phrase, after reading Charles Darwin's On the Origin of Species, in his Principles of Biology (1864), in which he drew parallels between his own economic theories and Darwin's biological ones: "This survival of the fittest, which I have here sought to express in mechanical terms, is that which Mr. Darwin has called 'natural selection', or the preservation of favoured races in the struggle for life."[2]

Darwin responded positively to Alfred Russel Wallace's suggestion of using Spencer's new phrase "survival of the fittest" as an alternative to "natural selection", and adopted the phrase in The Variation of Animals and Plants Under Domestication published in 1868.[2][3] In On the Origin of Species, he introduced the phrase in the fifth edition published in 1869,[4][5] intending it to mean "better designed for an immediate, local environment".[6][7]

By his own account, Herbert Spencer described a concept similar to "survival of the fittest" in his 1852 "A Theory of Population".[8] He first used the phrase after reading Charles Darwin's On the Origin of Species in his Principles of Biology of 1864[9] in which he drew parallels between his economic theories and Darwin's biological, evolutionary ones, writing, "This survival of the fittest, which I have here sought to express in mechanical terms, is that which Mr. Darwin has called 'natural selection', or the preservation of favored races in the struggle for life."[2]

In July 1866 Alfred Russel Wallace wrote to Darwin about readers thinking that the phrase "natural selection" personified nature as "selecting", and said this misconception could be avoided "by adopting Spencer's term" Survival of the fittest. Darwin promptly replied that Wallace's letter was "as clear as daylight. I fully agree with all that you say on the advantages of H. Spencer's excellent expression of 'the survival of the fittest'. This however had not occurred to me till reading your letter. It is, however, a great objection to this term that it cannot be used as a substantive governing a verb". Had he received the letter two months earlier, he would have worked the phrase into the fourth edition of the Origin which was then being printed, and he would use it in his next book on "Domestic Animals etc.".[2]

Darwin wrote on page 6 of The Variation of Animals and Plants Under Domestication published in 1868, "This preservation, during the battle for life, of varieties which possess any advantage in structure, constitution, or instinct, I have called Natural Selection; and Mr. Herbert Spencer has well expressed the same idea by the Survival of the Fittest. The term 'natural selection' is in some respects a bad one, as it seems to imply conscious choice; but this will be disregarded after a little familiarity". He defended his analogy as similar to language used in chemistry, and to astronomers depicting the "attraction of gravity as ruling the movements of the planets", or the way in which "agriculturists speak of man making domestic races by his power of selection". He had "often personified the word Nature; for I have found it difficult to avoid this ambiguity; but I mean by nature only the aggregate action and product of many natural laws,and by laws only the ascertained sequence of events."[3]

In the first four editions of On the Origin of Species, Darwin had used the phrase "natural selection".[10] In Chapter 4 of the 5th edition of The Origin published in 1869,[4] Darwin implies again the synonym: "Natural Selection, or the Survival of the Fittest".[5] By "fittest" Darwin meant "better adapted for the immediate, local environment", not the common modern meaning of "in the best physical shape" (think of a puzzle piece, not an athlete).[6] In the introduction he gave full credit to Spencer, writing "I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert Spencer of the Survival of the Fittest is more accurate, and is sometimes equally convenient."[11]

In The Man Versus The State, Spencer used the phrase in a postscript to justify a plausible explanation of how his theories would not be adopted by "societies of militant type". He uses the term in the context of societies at war, and the form of his reference suggests that he is applying a general principle.[12]

"Thus by survival of the fittest, the militant type of society becomes characterized by profound confidence in the governing power, joined with a loyalty causing submission to it in all matters whatever".[13]

Though Spencer's conception of organic evolution is commonly interpreted as a form of Lamarckism,[a] Herbert Spencer is sometimes credited with inaugurating Social Darwinism. The phrase "survival of the fittest" has become widely used in popular literature as a catchphrase for any topic related or analogous to evolution and natural selection. It has thus been applied to principles of unrestrained competition, and it has been used extensively by both proponents and opponents of Social Darwinism.[citation needed]

Evolutionary biologists criticise the manner in which the term is used by non-scientists and the connotations that have grown around the term in popular culture. The phrase also does not help in conveying the complex nature of natural selection, so modern biologists prefer and almost exclusively use the term natural selection. The biological concept of fitness refers to both reproductive success (fecundity selection), as well as survival (viability selection), and is not prescriptive in the specific ways in which organisms can be more "fit" by having phenotypic characteristics that enhance survival and reproduction (which was the meaning that Spencer had in mind).[15]

While the phrase "survival of the fittest" is often used to mean "natural selection", it is avoided by modern biologists, because the phrase can be misleading. For example, survival is only one aspect of selection, and not always the most important. Another problem is that the word "fit" is frequently confused with a state of physical fitness. In the evolutionary meaning "fitness" is the rate of reproductive output among a class of genetic variants.[16]

The phrase can also be interpreted to express a theory or hypothesis: that "fit" as opposed to "unfit" individuals or species, in some sense of "fit", will survive some test. Nevertheless, when extended to individuals it is a conceptual mistake, the phrase is a reference to the transgenerational survival of the heritable attributes; particular individuals are quite irrelevant. This becomes more clear when referring to Viral quasispecies, in survival of the flattest, which makes it clear to survive makes no reference to the question of even being alive itself; rather the functional capacity of proteins to carry out work.

Interpretations of the phrase as expressing a theory are in danger of being tautological, meaning roughly "those with a propensity to survive have a propensity to survive"; to have content the theory must use a concept of fitness that is independent of that of survival.[6][17]

Interpreted as a theory of species survival, the theory that the fittest species survive is undermined by evidence that while direct competition is observed between individuals, populations and species, there is little evidence that competition has been the driving force in the evolution of large groups such as, for example, amphibians, reptiles, and mammals. Instead, these groups have evolved by expanding into empty ecological niches.[18] In the punctuated equilibrium model of environmental and biological change, the factor determining survival is often not superiority over another in competition but ability to survive dramatic changes in environmental conditions, such as after a meteor impact energetic enough to greatly change the environment globally. The main land dwelling animals to survive the K-Pg impact 66million years ago had the ability to live in tunnels, for example.[citation needed]

In 2010 Sahney et al. argued that there is little evidence that intrinsic, biological factors such as competition have been the driving force in the evolution of large groups. Instead, they cited extrinsic, abiotic factors such as expansion as the driving factor on a large evolutionary scale. The rise of dominant groups such as amphibians, reptiles, mammals and birds occurred by opportunistic expansion into empty ecological niches and the extinction of groups happened due to large shifts in the abiotic environment.[18]

It has been claimed that "the survival of the fittest" theory in biology was interpreted by late 19th century capitalists as "an ethical precept that sanctioned cut-throat economic competition" and led to the advent of the theory of "social Darwinism" which was used to justify laissez-faire economics, war and racism[citation needed]. However, these ideas pre-date and commonly contradict Darwin's ideas, and indeed their proponents rarely invoked Darwin in support.[citation needed] The use of the term "social Darwinism" as a critique of capitalist ideologies was introduced in Richard Hofstadter's Social Darwinism in American Thought published in 1944.[19]

Russian zoologist and anarchist Peter Kropotkin viewed the concept of "survival of the fittest" as supporting co-operation rather than competition. In his book Mutual Aid: A Factor of Evolution he set out his analysis leading to the conclusion that the fittest was not necessarily the best at competing individually, but often the community made up of those best at working together. He concluded that

In the animal world we have seen that the vast majority of species live in societies, and that they find in association the best arms for the struggle for life: understood in its wide Darwinian sense not as a struggle for the sheer means of existence, but as a struggle against all natural conditions unfavourable to the species. The animal species, in which individual struggle has been reduced to its narrowest limits, and the practice of mutual aid has attained the greatest development, are invariably the most numerous, the most prosperous, and the most open to further progress.[20]

Applying this concept to human society, Kropotkin presented mutual aid as one of the dominant factors of evolution, the other being self-assertion, and concluded that

In the practice of mutual aid, which we can retrace to the earliest beginnings of evolution, we thus find the positive and undoubted origin of our ethical conceptions; and we can affirm that in the ethical progress of man, mutual support not mutual struggle has had the leading part. In its wide extension, even at the present time, we also see the best guarantee of a still loftier evolution of our race.[21]

"Survival of the fittest" is sometimes claimed to be a tautology.[22] The reasoning is that if one takes the term "fit" to mean "endowed with phenotypic characteristics which improve chances of survival and reproduction" (which is roughly how Spencer understood it), then "survival of the fittest" can simply be rewritten as "survival of those who are better equipped for surviving". Furthermore, the expression does become a tautology if one uses the most widely accepted definition of "fitness" in modern biology, namely reproductive success itself (rather than any set of characters conducive to this reproductive success). This reasoning is sometimes used to claim that Darwin's entire theory of evolution by natural selection is fundamentally tautological, and therefore devoid of any explanatory power.[22]

However, the expression "survival of the fittest" (taken on its own and out of context) gives a very incomplete account of the mechanism of natural selection. The reason is that it does not mention a key requirement for natural selection, namely the requirement of heritability. It is true that the phrase "survival of the fittest", in and by itself, is a tautology if fitness is defined by survival and reproduction. Natural selection is the portion of variation in reproductive success that is caused by heritable characters (see the article on natural selection).[22]

If certain heritable characters increase or decrease the chances of survival and reproduction of their bearers, then it follows mechanically (by definition of "heritable") that those characters that improve survival and reproduction will increase in frequency over generations. This is precisely what is called "evolution by natural selection". On the other hand, if the characters which lead to differential reproductive success are not heritable, then no meaningful evolution will occur, "survival of the fittest" or not: if improvement in reproductive success is caused by traits that are not heritable, then there is no reason why these traits should increase in frequency over generations. In other words, natural selection does not simply state that "survivors survive" or "reproducers reproduce"; rather, it states that "survivors survive, reproduce and therefore propagate any heritable characters which have affected their survival and reproductive success". This statement is not tautological: it hinges on the testable hypothesis that such fitness-impacting heritable variations actually exist (a hypothesis that has been amply confirmed.)[22]

Momme von Sydow suggested further definitions of 'survival of the fittest' that may yield a testable meaning in biology and also in other areas where Darwinian processes have been influential. However, much care would be needed to disentangle tautological from testable aspects. Moreover, an "implicit shifting between a testable and an untestable interpretation can be an illicit tactic to immunize natural selection ... while conveying the impression that one is concerned with testable hypotheses".[17][23]

Skeptic Society founder and Skeptic magazine publisher Michael Shermer addresses the tautology problem in his 1997 book, Why People Believe Weird Things, in which he points out that although tautologies are sometimes the beginning of science, they are never the end, and that scientific principles like natural selection are testable and falsifiable by virtue of their predictive power. Shermer points out, as an example, that population genetics accurately demonstrate when natural selection will and will not effect change on a population. Shermer hypothesizes that if hominid fossils were found in the same geological strata as trilobites, it would be evidence against natural selection.[24]

Read more:

Survival of the fittest - Wikipedia

Image: A scene from "Molecular Machines ATP Synthase: The Power Plant of the Cell," via Discovery Institute.

Our biologist colleague Michael Behehas written a wonderful cover story forWorld Magazine. His theme is how science has vindicated the words of the Psalmist: I will praise thee; for I am fearfully and wonderfully made: marvellous are thy works; and that my soul knoweth right well.

That inference to intelligent design recognizing a purposeful arrangement of parts in biological systems, large and small doesnt require a scientist to draw it. It was available to the thoughtful observer of life thousands of years. But the closer and deeper that technology has permitted us to peer into such systems, the more evident it has become that they reflect a deliberate design.

Behe traces sciences progress from Aristotle to Galen to William Harvey, Marcello Malpighi, Antonie van Leeuwenhoek, and modern scientists who study molecular machines. He recounts regarding ATP synthase:

ATP synthase is not simple. Comprising thousands of amino acid building blocks in about 10 kinds of protein chains, its intricate structure carefully directs a flow of acid particles, beginning from outside the cell, through deep channels in the machines organization, into the cells interior. Somehow, like the cascade of water over a hydroelectric dam that turns a turbine, the flow of acid through the channels rotates a central camshaft. The cams push against multiple discrete areas of a stationary region of the synthase, distorting their shapes. The distortion forces together two bound feed-chemicals, ADP and phosphate, provoking them to react to yield the energy-rich-yet-stable molecule ATP. As the camshaft completes a turn, the ATP is released into the cell, and the machine begins another cycle. Incredibly, the many copies of the machine in each person produce about 150 pounds of ATP moleculesevery day, but each is used rapidly as energy in effect, recharging each cell like a reusable battery.

Read the rest of Behes essay forWorldhere.

Go here to see the original:

Michael Behe: Game Over for Darwinism | Evolution News

Photo: Gnter Bechly in a scene from the documentary Revolutionary, via Discovery Institute.

I was fascinated by a new article inSalvo Magazineby our paleontologist colleague Gnter Bechly about his journey to faith. He commented to me:

I embraced ID for purely scientific reasons many years before I embraced theism and Christianity, for totally unrelated philosophical and historical reasons. Indeed, I have no theological issues with Darwinism at all, and my faith would be unaffected if Darwinism were to turn out to be true, and my critique of neo-Darwinism and endorsement of ID would be unaffected if Christianity or even generic theism should turn out to be false. After all, my preferred model of ID is not based on direct divine intervention but on a kind ofquantum computation on the level of entangled genes.

That said, please read his remarks atSalvo. I found the conclusion to be particularly candid and moving:

In hindsight, I think it was definitely due to the grace of the Holy Spirit that I did not give up but always returned to do more reading on remaining issues, which included all of the usual suspects, like the problem of evil, atrocities in the Old Testament, biblical anachronisms, contradictions in the Gospels, and unbelievable miracles you name it. Ultimately, I reached a point where the evidence and arguments were so overwhelming, while most of my problems with Christianity could be resolved, that I had no choice but to surrender to the call of Christ.

So how has my Christian faith developed since my conversion? Actually, it turned out to be very difficult to pray when you had never prayed before your fiftieth birthday. Even though I delved into Scripture and prayed for a more direct experience of Gods presence and personal relationship with Christ, this has not manifested yet. I hope this will change with time. Maybe it is simply my destiny to be an evidentialist Christian, or maybe I still have some way to go on this remarkable journey.

I can identify with the last paragraph, in the context of my own different religious tradition, with certain other differences as well. Thank you, Gnter, for your openness about all this.Read the rest atSalvo.

Link:

Gnter Bechlys Journey to Faith - Discovery Institute

Photo credit: Clyde Gravenberch via Unsplash.

Evidence is growing that organisms share existing genetic information horizontally, not just vertically. This has immense implications for neo-Darwinian theory that are not yet fully recognized. If traits can be shared across species, genera and even phyla, they are not being inherited from common ancestors. The findings might also cast stories about convergence and co-evolution in a completely different light. Lets look at some of the news on this front.

Last month,Current Biologyposted a Primer on Introgression by four authors. Introgression refers to lasting transfer of DNA from one of the species into the genome of the other by means of hybridization and backcrossing. Basically, it describes the incorporation of the DNA from one species into another.

Over the last few decades, advances in genomics havetransformed our understanding of the frequency of gene flow between speciesand with it our ideas about reproductive isolation in nature. These advances have uncovered a rich and often complicated history ofgenetic exchange between species demonstrating that such genetic introgression isan important evolutionary process widespread across the tree of life(Figure 1). [Emphasis added.]

Figure 1 in this open-access paper shows nine photos of creatures where gene flow has been inferred. They include vastly different organisms, from bacteria to birds, fish, and mammals including humans. The authors strive to maintain Darwinism in their explanation, but this realization undermines what previously was explained by convergence or by independent origins of traits:

Instead of waiting for a beneficial mutation to arise, gene flow can instead introducevariation that has been pre-tested by selection, allowing species to evolve rapidly. For instance, alleles causing brown winter coat color in snowshoe hares (Figure 1E), early flowering time in sunflowers or serpentine soil tolerance in Arabidopsis haveintrogressed from closely related species, which has facilitated adaptationto new environments.

The authors do not speculate at this time how common adaptive introgression might be.

In news from theFlorida Museum of Natural History, biologists discussed how a new genome for ferns reveals a history of DNA hoarding and kleptomania. The article is classified under Evolution but what is Darwinian about it?

The hoarding part refers to ferns having 720 pairs of chromosomes crammed into each of its nuclei for unknown evolutionary reasons. Whole-gene duplication is not uncommon in plants and animals, but most species slim down their genomes over time. Why has this not happened in ferns? Geneticists are still trying tofigure out the evolutionary processunderlying thisparadox, the article says.

The kleptomania claim refers to the surprise discovery that ferns stole the genes for several of their anti-herbivory toxins from bacteria.

Rather thanevolvingthis toxinon its own, Ceratopteris appears to haveobtained it directly from bacteriathrough a process called horizontal gene transfer. And given that there were multiple copies of the gene spread out among three separate chromosomes, itslikely this happened more than once.

The article references a 2014 study that showed another instance of kleptomania. Ferns seem to have inherited genes for thriving in shade from distantly related plants, but exactly how organisms separated by millions of years of evolution are able to swap fully functional genes remains unclear.

The mechanisms behind horizontal gene transfer remain one of theleast investigatedareas of land plant evolution, Doug Soltis explained. Over evolutionary timescales, its a bit like winning the lottery. Any time a plant is wounded, its interior is susceptible to invasion from microbes, butfor their DNA to be incorporated into the genome seems amazing.

These examples illustrate a sea change in thinking about horizontal gene transfer (HGT), which was formerly thought to be restricted to microbes.

A related preprint byHaimlichet al. onbioRxivinvestigated Widespread horizontal gene transfer between plants and their microbiota. Finding 180 genes that indicated prevalent horizontal gene transfer, they concluded,

Our results suggest that horizontal gene transfer between hosts and their microbiota isa significant and active evolutionary mechanismthat contributednew traitsto plants and their commensal microbiota.

Crediting evolution seems stretched, though. Information shared is not the same as information innovated, nor is borrowing a book as difficult as writing one.

Another preprint onbioRxivreported introgression between highly divergent sea squirt genomes that were brought into contact by humans. The paper suggests that hybridization of these incompletely isolated species offered an adaptive breakthrough for the organisms. What other cases of assumed allopatric speciation or convergence might turn out to be cases of introgression or HGT? Can life share library books of genes across distant species?

Speaking of bacteria,Duke Universityproclaims that Microbial Communities Stay Healthy by Swapping Knowledge. How and why microbes do this prompted a metaphor that portrays intelligent action:

Put another way, aconstruction crewcould be extremely resilient toelectriciansquitting if theplumberson site also knew how to wire a building. But the same crew would be even more resilientif the remaining electricians could simply transfer their expertiseto anyone on the job when needed, no matter their profession.

Dr. Lingchong You at Duke considers HGT a dynamic division of labor by which bacteria maintain their health in nature.

With these reassessments of heredity in mind, how much of assumed human evolution could be explained by gene sharing instead of by the neo-Darwinian mutation-selection model? Have human beings been sharing library books or downloading each others software apps instead of writing them from scratch?

News from theUniversity of Tbingensays that paleoanthropologists are considering the degree to which genetic hybridization affected the human skeleton and skull shape.

Many people living today have a small component of Neanderthal DNA in their genes, suggestingan important role for admixture with archaic human lineages in the evolution of our species.Paleogenetic evidence indicates thathybridizationwithNeanderthals and other ancient groupsoccurredmultiple times, with our species history resembling morea network or braided stream than a tree. Clearly the origin of humankind wasmore complex than previously thought.

Its not the percentage of Neanderthal DNA that affects the phenotype, the researchers are finding, but the presence of particular genetic variants instead.

Similar conclusions are being reached atNorth Carolina State Universitywhere a news item says that Ancient DNA caused a revolution in how we think about human evolution. Out is the old single-file march of progress from ape to man. In is the a series of streams that converge and diverge at multiple points. The exploratory study going on at NC State is changing the view that evolution is driven by external environmental factors, such as climate, and toward the view that internal gene flow causes the variations in human anatomy.

The Tbingen story notes that evolutionary innovation by hybridization is being found everywhere:

In other organisms from plants to large mammals hybridization is known to produceevolutionary innovation, includingoutcomes that are both novel and diverse. It is estimated that about 10 percent of animal species produce hybrids, including, for example,bovids, bears, cats and canids, Ackermann says. Hybrids are also known inprimates, our close relatives, such as baboons, she says. Because hybridizationintroduces new variation, and creates new combinations of variation, this can facilitate particularly rapid evolution, especially when facing new or changing environmental conditions.

A question arises whether these variations and combinations of variations are random when introduced by gene flow instead of mutation. If the latter, then old-school Darwinians might argue that they are merely additional manifestations of neo-Darwinisms unguided process of random variation and selection.

But if these shared genes are instead modular pieces of functional information that are pre-adapted to join up in certain ways, then biologists will need to consider whether the source of that information requires an intelligent cause. The case for intelligent design in instances of gene flow can be further strengthened by observing whether newly incorporated genes are epigenetically regulated, targeted to functional loci, and responsive to signals from the environment. If so, organisms have been equipped with mechanisms to ensure robustness to changing conditions. That impliesForesight.

See the article here:

Gene Sharing Is More Widespread than Thought | Evolution News