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What is the modern state of the theory of evolution?

What is the modern state of the theory of evolution?



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When I studied biology at my medical school, we used to learn topics around a century old: the famous Darwin's voyage on "Beagle" to the Galapagos Islands, the classical triad of his Theory of Evolution, etc.

At the same time we were told that there is no evidence found in nature for many of these statements of his evolutional theory. For example, people studied wildlife around Chernobyl and found that no new species emerged due to much higher mutation rate as a consequence of radiation. On the contrary, there were no significant differences between the species living under elevated radiation level and those living in "normal" conditions.

Do these facts somehow influence our understanding of the theory of evolution? Are there any breakthrough findings which happened in the last 20 years that prove or disprove it?


My friend Brightblades is right in one thing. It seems your teacher was working off a caricature of what the theory of evolution actually says. First of all, you should read Sklivvz's excellent answer at this question. Now to address the elephant in the room, the accident at Chernobyl only happened in 1986. That was only 26 years ago. In that timeframe, noticeable effects in an animal population really would not be at all noticeable. Furthermore, the paper cited by Marta Cz-C actually shows that there have been some changes (in fungi though, not animals).

fungi seem to interact with the ionizing radiation differently from other Earth's inhabitants. Recent data show that melanized fungal species like those from Chernobyl's reactor respond to ionizing radiation with enhanced growth. Fungi colonize space stations and adapt morphologically to extreme conditions. Radiation exposure causes upregulation of many key genes, and an inducible microhomology-mediated recombination pathway could be a potential mechanism of adaptive evolution in eukaryotes.

Read the rest of the paper for more information on how there have been some other slight changes to fungi at Chernobyl as well as other locations throughout the world.

Now I am going to repeat a bunch of stuff from one of my web pages that talks about evolution. This web page is set up mostly to deal with creationist arguments, however, the caricature is so severe as to warrant this. As I said earlier, evolution is a population phenomenon.

Evolution acts upon heritable variation of characteristics, and you can only have variation of this sort within a population. A single individual organism, at least if its a multicellular eukaryote, has a fixed genome. It can't change what it has inherited. But a large number of organisms can all have different genomes, and can disseminate variation via inheritance to the next generation. It is upon the population as a whole that evolution acts, with various mechanisms coming into play to remove some variations from the population, and propel other variations to numerical dominance within the population. The organisms in question remain part of that population, and within a generation, those organisms don't change. But the moment a new generation is produced, dissemination of variation can result in the appearance of a new feature in one or more members of that population. If that new feature leads to greater reproductive success for the organism possessing it, that feature spreads through the population, as more and more future offspring inherit it. Over time, the population changes, and more and more organisms with new features appear within that population.

Understanding inheritance basics and mechanisms for changes (genes), we have all that is needed for the appearance of cladogenesis events. Split a decent sized population of living organisms into two, and let's call these new, separate populations A and B. Now let a barrier be erected between population A and population B, so that individuals from one cannot reproduce with individuals from the other. This barrier can be an insurmountable physical obstacle, for example, but this need not be the only form such a barrier can take. Now, first of all, there is no reason whatsoever to think that population A and population B will start off in identical states to begin with. After all, those two populations were derived from an original population comprising lots of organisms with different genomes, and the likelihood of population A and population B being identical at the start of this process is vanishingly small. Then, once our barrier is erected, and our populations are allowed to reproduce separately from that point on, there is no reason to think that those populations will move in the same direction in the long term. Indeed, it is far more likely that they will be subject to different environmental and ecosystem influences, and those different environmental and ecosystem influences will shape the long term heredity of those populations. Indeed, that's all that natural selection IS - it's a single, concise term used to encapsulate all of those environmental and ecosystem influences succinctly, and additionally to encapsulate the fact that those influences affect the inheritance of characteristics within a population over the long term.

As a consequence, any two separated populations of living organisms, that originated from a single population, will diverge from each other. If the extant influences on those two populations are sufficiently different, that divergence will take place more rapidly. Eventually, we will arrive at a point where those two populations become sufficiently diverged from each other that individuals from population A can no longer produce viable offspring with individuals from population B, and vice versa. When this happens, we have a speciation event. Indeed, this has been observed taking place in the wild AND in the laboratory, and has been documented in the relevant scientific papers. So, if anyone wishes to assert that there are 'magic barriers' to speciation or other cladogenesis events, then reality doesn't agree.

You will not have any animals giving birth to any radically different animals as a result of radiation. Most changed sue to radiation will not provide any particular advantage to an animal anyway. Also, a change may also be dependent on a previous change and require many generations to fully manifest. All this was demonstrated by the long term evolution experiment led by Richard Lenski at Michigan State University.

So in essence, your teacher was just plain wrong. As for the findings of the past 20 years, we are always learning more and more. For instance, there has been an explosive capability in DNA analysis and sequencing, which has only provided more support for the theory of evolution. A mechanism that Charles Darwin could not have had any idea about in his day and age, yet it perfectly supports his conclusions. Again, read the answer provided at Skeptics.


Perhaps the biggest advance since you studied evolution has been the sequencing of DNA and it's exhaustive analysis and decoding by computers and mathematicians.

Previously the proofs of evolution were geographical, anatomical, genetic, fossil, and a variety of other proofs.

Today there is also a vast library of genetic information.

You, judges. police, doctors and families all trust genetic tests for parentage, they provide incontrovertible proof of family relationships.

Here are 33000 sequenced species. https://www.ncbi.nlm.nih.gov/genome/browse/#!/overview/

If a single one of them showed that it had appeared spontaneously and was not related in an evolutionary tree, people would be amazed, evolution would have been disproved, 2+2 would make 7, people would be confused.

Fortunately all the 33000+ species sequenced recently since 2000 have proven an inherited relationship between all species in a very orderly and hyerarchical evolutionary tree. They find where many genes arise, how humans diversify and new genes appeared, what genes we share with mammals and lizards and fish.

It's a bit like having 33000 forensic pathology tests all in agreement that evolution is very real, it's like the block chain of bit torrent, DNA code is a very powerful method of understanding evolutionary relationships with massive precision and statistical depth.

Big surprises in evolution have happened too since 20 years, such as neanderthal DNA in humans, discovery of feathered dinosaurs and many flying dinosaurs species, 4,6 billion year old stromatolite fossils, and many others.


The state of modern evolutionary theory may not be what you think it is

I was rather surprised yesterday to see so much negative reaction to my statement that there's more to evolution than selection, and that random, not selective, changes dominate our history. It was in the context of what should be taught in our public schools, and I almost bought the line that we can only teach a simplified version of evolution in grade school, but then it sunk in that I was talking to a group of adults about the standard biological perspective, and their reactions were a mix of total bafflement, indignant rejection, and strange evasive waffling. Well, when should we talk about this stuff, then? Do I have to start making day trips to the local nursing home? Or maybe we should be honest from the very beginning about the complexity of modern evolutionary theory and how it has grown to be very different from what Darwin knew.

First thing you have to know: the revolution is over. Neutral and nearly neutral theory won. The neutral theory states that most of the variation found in evolutionary lineages is a product of random genetic drift. Nearly neutral theory is an expansion of that idea that basically says that even slightly advantageous or deleterious mutations will escape selection — they'll be overwhelmed by effects dependent on population size. This does not in any way imply that selection is unimportant, but only that most molecular differences will not be a product of adaptive, selective changes.

These theories describe different patterns of the distribution of mutations in populations. This diagram from Bromham & Penny (2003) will help you see the difference.

Selectionist, neutral and nearly neutral theories. a | Selectionist theory: early neo-Darwinian theories assumed that all mutations would affect fitness and, therefore, would be advantageous or deleterious, but not neutral. b | Neutral theory: the neutral theory considered that, for most proteins, neutral mutations exceeded those that were advantageous, but that differences in the relative proportions of neutral sites would influence the rate of molecular evolution (that is, more neutral sites would produce a faster overall rate of change). c | Nearly neutral theory: the fate of mutations with only slight positive or negative effect on fitness will depend on how population size affects the outcome.

The purple bars are mutations subject to purifying selection -- that is, deleterious mutations that are culled from the population. The green bars are mutations subject to positive selection, that confer some advantage to the individual carrying them. That's all people thought you would have under old school versions of evolution: every change would have some effect on the individual, and would be subject to selection (and then, of course, smart people started to wonder about genetic load and realizing that there were limitations to how much selection a population could tolerate).

Kimura and Ohta proposed, though, that many mutations would be neutral -- that is, changes to the sequence of a gene or the protein would have no effect on fitness, and would be effectively neutral. Since the genetic code is degenerate, with most amino acids coded for by more than one triplet, you could have synonymous changes to the DNA that would produce proteins with identical amino acid sequences. Further, protein structure and function may not be as precisely dependent on specific amino acid sequences as many people assume: there are key regulatory and active sites within proteins that are extremely sensitive to small amino acid changes, but other parts of the protein may be much more fault tolerant. That means that under neutral theory, we have to recognize that beige bar, which are mutations that have no effect on fitness.

Under nearly neutral theory, the domain of selection effects shrunk further, because it was realized that quantitatively, small deleterious and advantageous mutations, that is mutations that only conferred a slight difference in reproductive success, would be invisible against a noisy background of chance variation, and therefore could not be seen by selection. That's the blue bar mutations that we can see might cause a slight change to the efficiency of an enzyme, for instance, but are not significant enough to cause any difference in reproductive success, or are either lost or fixed by chance.

Now you might try to salvage your faith in the ultimate power of selection by suggesting that the neutral and nearly neutral mutations are really rare and can thus be ignored as negligible, therefore returning us to the world of selection theory…with just a little fuzzy slop around the boundary between the green and blue bars. That's untenable, though. We have molecular clocks.

When comparing the rates of change between homologous genes in different species, we had a bit of a surprise: they are very roughly, sloppily constant. That shouldn't be true under pure selection theory, but it turns out to make a lot of sense under nearly neutral theory. There is a tradeoff in the rate of mutations occurring, and in becoming fixed in a population. A very large population size will accumulate more mutations purely by chance, but the probability of a single mutation becoming fixed in the population is reduced under large population sizes. When you do the math, you discover that population size cancels out, and the frequency of novel forms becoming fixed over time is dependent solely on the mutation rate.

Think about that. If you compare two species, the number of nucleotide differences between them is basically going to be simply the mutation rate times the number of generations separating them from their last common ancestor. That's how we can use a molecular clock to date the time of divergence of two lineages.

Please note: this does not deny that the selection shapes specific traits in a species occurs — we do undergo evolutionary adaptation! It merely says that most of the genetic changes are random. We have to use specific analysis techniques, like the McDonald/Kreitman test, to detect the signature of selection out of the background noise of mutation.

This is just one example of an important concept that is overlooked when your education in evolution focuses solely on one simplistic version of the mechanisms of change. If you didn't know it, it's not your fault I graduated from high school never having the 'evolution' word uttered even once by a teacher, so if you've heard about natural selection, you're one up on me. But we can do better. That the high school level of instruction in evolutionary biology is stuck at around 1930 is a bug, not a feature, and we should aim to improve it.

I know, it's hard when a significant part of the population is stuck in the first millennium BCE, but we shouldn't use that as an excuse to dumb down education.

Now, because I so enjoyed the chaos that ensued after rejecting one small part of the Modern Synthesis, let me share with you something rather cool. It's a table from Eugene Koonin's The Logic of Chance, in which he summarizes some of the big changes between the Modern Synthesis that emerged in the era before molecular biology, and how most molecular biologists view evolution today. I expect an even more glorious freakout because he refers to this positively as a postmodern reassessment, and I know how much everyone loves post-modernism.

Postmodern reassessment of some central propositions of Darwin and Modern Synthesis

The material for evolution is provided primarily by random, heritable variation.

Only partly true. The repertoire of relevant random changes greatly expanded to include duplication of genes, genome regions, and entire genomes loss of genes and generally, genetic material HGT [horizontal gene transfer], including massive gene flux in cases of endosymbiosis invasion of mobile selfish elements and recruitment of sequences from them and more. More importantly, (quasi) directed (Lamarckian * ) variation is recognized as a major factor of evolution.

Fixation of (rare) beneficial changes by natural selection is the main driving force of evolution.

Only partly true. Natural (positive) selection is important but is only one of several fundamental factors of evolution and is not quantitatively dominant. Neutral processes combined with purifying selection dominate evolution, and direct effects of environmental cues on the genome ([quasi] Lamarckian phenomena) are important as well.

The variations fixed by natural selection are "infinitesimally small." Evolution adheres to gradualism.

False. Even single gene duplications and HGT of single genes are by no means "infinitesimally small," nor are deletion or acquisition of larger regions, genome rearrangements, whole-genome duplications, and, most dramatically, endosymbiosis. Gradualism is not the principal regime of evolution. [And I would add that even point mutations can have large phenotypic effects. --pzm]

Uniformitarianism: Evolutionary processes have remained largely the same throughout the evolution of life.

Only partly true. Present-day evolutionary processes were important since the origin of replication. However, major transitions in evolution, such as the origin of eukaryotes, could be brought about by (effectively) unique events such as endosymbiosis, and the earliest stages of evolution (pre-LUCA [last universal common ancestor]) partially relied on distinct processes not involved in subsequent "normal" evolution.

Evolution by natural selection tends to produce increasingly complex adaptive features of organisms, hence progress is a general trend in evolution.

False. Genome complexity probably evolved as a "genomic syndrome" cause by weak purifying selection in small populations, not as an adaptation. There is no consistent trend toward increasing complexity in evolution, and the notion of evolutionary progress is unwarranted.

The entire evolution of life can be depicted as a single "big tree."

False. The discovery of the fundamental contribution of HGT and mobile genetic elements to genome evolution invalidates the TOL concept in its original sense. However, trees remain essential templates to represent evolution of individual genes and many phases of evolution in groups of relatively close organisms. The possibility of salvaging the TOL as a central trend of evolution remains.

All extant cellular life forms descend from very few ancestral forms (and probably one, LUCA).

True. Comparative genomics leaves no doubt of the common ancestry of cellular life. However, it also yields indications that LUCA(s) might have been very different from modern cells.

I would add another significant distinction. Under the modern synthesis, populations are primarily seen as plastic and responsive to changes in the environment, producing species that are most strongly marked by adaptive changes. In the postmodern evolutionary view, history dominates -- most of the properties of a species are a contingent product of its ancestors' attributes. "Everything is the way it is because it got that way." Everything you see in an organism is a consequence of its history, with the addition of a few unique adaptive fillips, and that has two significant implications: you can't understand an organism without recognizing the impact of its phylogeny, and the modern form preserves ancestral relationships that can be analyzed to discern that history.

And that, of course, demolishes the bogus distinction between historical and observational science that Ken Ham laughably makes. When I observe a fruit fly or a zebrafish or a human being, I am seeing its history made manifest in its structure. See also John Timmer's recent post on history and science for more.

Bromham L, Penny D (2003) The modern molecular clock. Nat Rev Genet 4(3):216-24.

* I'm not going to get into the evidence for quasi-Lamarckian evolution here, but I will say that there is good evidence for some of it: Koonin discusses the CRISPR-Cas system of adaptive immunity in bacteria. Maybe some other time I can write that up.


The state of modern evolutionary theory may not be what you think it is

I was rather surprised yesterday to see so much negative reaction to my statement that there's more to evolution than selection, and that random, not selective, changes dominate our history. It was in the context of what should be taught in our public schools, and I almost bought the line that we can only teach a simplified version of evolution in grade school, but then it sunk in that I was talking to a group of adults about the standard biological perspective, and their reactions were a mix of total bafflement, indignant rejection, and strange evasive waffling. Well, when should we talk about this stuff, then? Do I have to start making day trips to the local nursing home? Or maybe we should be honest from the very beginning about the complexity of modern evolutionary theory and how it has grown to be very different from what Darwin knew.

First thing you have to know: the revolution is over. Neutral and nearly neutral theory won. The neutral theory states that most of the variation found in evolutionary lineages is a product of random genetic drift. Nearly neutral theory is an expansion of that idea that basically says that even slightly advantageous or deleterious mutations will escape selection — they'll be overwhelmed by effects dependent on population size. This does not in any way imply that selection is unimportant, but only that most molecular differences will not be a product of adaptive, selective changes.

These theories describe different patterns of the distribution of mutations in populations. This diagram from Bromham & Penny (2003) will help you see the difference.

Selectionist, neutral and nearly neutral theories. a | Selectionist theory: early neo-Darwinian theories assumed that all mutations would affect fitness and, therefore, would be advantageous or deleterious, but not neutral. b | Neutral theory: the neutral theory considered that, for most proteins, neutral mutations exceeded those that were advantageous, but that differences in the relative proportions of neutral sites would influence the rate of molecular evolution (that is, more neutral sites would produce a faster overall rate of change). c | Nearly neutral theory: the fate of mutations with only slight positive or negative effect on fitness will depend on how population size affects the outcome.

The purple bars are mutations subject to purifying selection -- that is, deleterious mutations that are culled from the population. The green bars are mutations subject to positive selection, that confer some advantage to the individual carrying them. That's all people thought you would have under old school versions of evolution: every change would have some effect on the individual, and would be subject to selection (and then, of course, smart people started to wonder about genetic load and realizing that there were limitations to how much selection a population could tolerate).

Kimura and Ohta proposed, though, that many mutations would be neutral -- that is, changes to the sequence of a gene or the protein would have no effect on fitness, and would be effectively neutral. Since the genetic code is degenerate, with most amino acids coded for by more than one triplet, you could have synonymous changes to the DNA that would produce proteins with identical amino acid sequences. Further, protein structure and function may not be as precisely dependent on specific amino acid sequences as many people assume: there are key regulatory and active sites within proteins that are extremely sensitive to small amino acid changes, but other parts of the protein may be much more fault tolerant. That means that under neutral theory, we have to recognize that beige bar, which are mutations that have no effect on fitness.

Under nearly neutral theory, the domain of selection effects shrunk further, because it was realized that quantitatively, small deleterious and advantageous mutations, that is mutations that only conferred a slight difference in reproductive success, would be invisible against a noisy background of chance variation, and therefore could not be seen by selection. That's the blue bar mutations that we can see might cause a slight change to the efficiency of an enzyme, for instance, but are not significant enough to cause any difference in reproductive success, or are either lost or fixed by chance.

Now you might try to salvage your faith in the ultimate power of selection by suggesting that the neutral and nearly neutral mutations are really rare and can thus be ignored as negligible, therefore returning us to the world of selection theory…with just a little fuzzy slop around the boundary between the green and blue bars. That's untenable, though. We have molecular clocks.

When comparing the rates of change between homologous genes in different species, we had a bit of a surprise: they are very roughly, sloppily constant. That shouldn't be true under pure selection theory, but it turns out to make a lot of sense under nearly neutral theory. There is a tradeoff in the rate of mutations occurring, and in becoming fixed in a population. A very large population size will accumulate more mutations purely by chance, but the probability of a single mutation becoming fixed in the population is reduced under large population sizes. When you do the math, you discover that population size cancels out, and the frequency of novel forms becoming fixed over time is dependent solely on the mutation rate.

Think about that. If you compare two species, the number of nucleotide differences between them is basically going to be simply the mutation rate times the number of generations separating them from their last common ancestor. That's how we can use a molecular clock to date the time of divergence of two lineages.

Please note: this does not deny that the selection shapes specific traits in a species occurs — we do undergo evolutionary adaptation! It merely says that most of the genetic changes are random. We have to use specific analysis techniques, like the McDonald/Kreitman test, to detect the signature of selection out of the background noise of mutation.

This is just one example of an important concept that is overlooked when your education in evolution focuses solely on one simplistic version of the mechanisms of change. If you didn't know it, it's not your fault I graduated from high school never having the 'evolution' word uttered even once by a teacher, so if you've heard about natural selection, you're one up on me. But we can do better. That the high school level of instruction in evolutionary biology is stuck at around 1930 is a bug, not a feature, and we should aim to improve it.

I know, it's hard when a significant part of the population is stuck in the first millennium BCE, but we shouldn't use that as an excuse to dumb down education.

Now, because I so enjoyed the chaos that ensued after rejecting one small part of the Modern Synthesis, let me share with you something rather cool. It's a table from Eugene Koonin's The Logic of Chance, in which he summarizes some of the big changes between the Modern Synthesis that emerged in the era before molecular biology, and how most molecular biologists view evolution today. I expect an even more glorious freakout because he refers to this positively as a postmodern reassessment, and I know how much everyone loves post-modernism.

Postmodern reassessment of some central propositions of Darwin and Modern Synthesis

The material for evolution is provided primarily by random, heritable variation.

Only partly true. The repertoire of relevant random changes greatly expanded to include duplication of genes, genome regions, and entire genomes loss of genes and generally, genetic material HGT [horizontal gene transfer], including massive gene flux in cases of endosymbiosis invasion of mobile selfish elements and recruitment of sequences from them and more. More importantly, (quasi) directed (Lamarckian * ) variation is recognized as a major factor of evolution.

Fixation of (rare) beneficial changes by natural selection is the main driving force of evolution.

Only partly true. Natural (positive) selection is important but is only one of several fundamental factors of evolution and is not quantitatively dominant. Neutral processes combined with purifying selection dominate evolution, and direct effects of environmental cues on the genome ([quasi] Lamarckian phenomena) are important as well.

The variations fixed by natural selection are "infinitesimally small." Evolution adheres to gradualism.

False. Even single gene duplications and HGT of single genes are by no means "infinitesimally small," nor are deletion or acquisition of larger regions, genome rearrangements, whole-genome duplications, and, most dramatically, endosymbiosis. Gradualism is not the principal regime of evolution. [And I would add that even point mutations can have large phenotypic effects. --pzm]

Uniformitarianism: Evolutionary processes have remained largely the same throughout the evolution of life.

Only partly true. Present-day evolutionary processes were important since the origin of replication. However, major transitions in evolution, such as the origin of eukaryotes, could be brought about by (effectively) unique events such as endosymbiosis, and the earliest stages of evolution (pre-LUCA [last universal common ancestor]) partially relied on distinct processes not involved in subsequent "normal" evolution.

Evolution by natural selection tends to produce increasingly complex adaptive features of organisms, hence progress is a general trend in evolution.

False. Genome complexity probably evolved as a "genomic syndrome" cause by weak purifying selection in small populations, not as an adaptation. There is no consistent trend toward increasing complexity in evolution, and the notion of evolutionary progress is unwarranted.

The entire evolution of life can be depicted as a single "big tree."

False. The discovery of the fundamental contribution of HGT and mobile genetic elements to genome evolution invalidates the TOL concept in its original sense. However, trees remain essential templates to represent evolution of individual genes and many phases of evolution in groups of relatively close organisms. The possibility of salvaging the TOL as a central trend of evolution remains.

All extant cellular life forms descend from very few ancestral forms (and probably one, LUCA).

True. Comparative genomics leaves no doubt of the common ancestry of cellular life. However, it also yields indications that LUCA(s) might have been very different from modern cells.

I would add another significant distinction. Under the modern synthesis, populations are primarily seen as plastic and responsive to changes in the environment, producing species that are most strongly marked by adaptive changes. In the postmodern evolutionary view, history dominates -- most of the properties of a species are a contingent product of its ancestors' attributes. "Everything is the way it is because it got that way." Everything you see in an organism is a consequence of its history, with the addition of a few unique adaptive fillips, and that has two significant implications: you can't understand an organism without recognizing the impact of its phylogeny, and the modern form preserves ancestral relationships that can be analyzed to discern that history.

And that, of course, demolishes the bogus distinction between historical and observational science that Ken Ham laughably makes. When I observe a fruit fly or a zebrafish or a human being, I am seeing its history made manifest in its structure. See also John Timmer's recent post on history and science for more.

Bromham L, Penny D (2003) The modern molecular clock. Nat Rev Genet 4(3):216-24.

* I'm not going to get into the evidence for quasi-Lamarckian evolution here, but I will say that there is good evidence for some of it: Koonin discusses the CRISPR-Cas system of adaptive immunity in bacteria. Maybe some other time I can write that up.


The theory of evolution: What scientists believe it is, and is not.

  • "Nothing in biology makes sense except in the light of evolution." Theodosius Dobzhansky, "The American Biology Teacher" (1973).

Source of this essay:

The following essay is based on many documents found on the Internet and in reference texts. Definitions are taken from a report issued in 1997 by the National Association of Biology Teachers. The full statement is available online. 1That statement was revised by the NABT from an earlier, 1995 statement. The 1997 version was subsequently endorsed by:

The Society for the Study of Evolution, 1998-JUN.
The American Association of Physical Anthropologists, in 1998-JUL.

Definitions:

Common beliefs that are misunderstood:

Studies of the origin of the first life form, of the origin of the earth, and the origin of the universe itself do not form part of the theory of evolution. Such studies are pursued within different scientific disciplines. Research into the origin of the first form of life is called abiogenesis, and is not part of evolution. The origin of the universe and and its changes over time are called cosmology.

Some proponents of other belief systems often loosely use the term "evolution" to refer to change in:

Plant and animal species,
The earth itself,
Individual stars,
Individual galaxies,
etc.

Strictly speaking, Evolution really only deals with species of living -- or once living -- biological species.


The theory of evolution: What scientists believe it is, and is not.

  • "Nothing in biology makes sense except in the light of evolution." Theodosius Dobzhansky, "The American Biology Teacher" (1973).

Source of this essay:

The following essay is based on many documents found on the Internet and in reference texts. Definitions are taken from a report issued in 1997 by the National Association of Biology Teachers. The full statement is available online. 1That statement was revised by the NABT from an earlier, 1995 statement. The 1997 version was subsequently endorsed by:

The Society for the Study of Evolution, 1998-JUN.
The American Association of Physical Anthropologists, in 1998-JUL.

Definitions:

Common beliefs that are misunderstood:

Studies of the origin of the first life form, of the origin of the earth, and the origin of the universe itself do not form part of the theory of evolution. Such studies are pursued within different scientific disciplines. Research into the origin of the first form of life is called abiogenesis, and is not part of evolution. The origin of the universe and and its changes over time are called cosmology.

Some proponents of other belief systems often loosely use the term "evolution" to refer to change in:

Plant and animal species,
The earth itself,
Individual stars,
Individual galaxies,
etc.

Strictly speaking, Evolution really only deals with species of living -- or once living -- biological species.


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What are the different Theories of Evolution?

It is the first theory of evolution proposed by Jean Baptiste de Lamarck (1744-1829) in 1801 and 1809 (in book Philosophic Zoologique) which proposes that organisms undergo changes for adapting themselves to environment and the characters thus acquired are passed on to the next generation. Lamarckism is popularly called ‘theory of inheritance of acquired characters’.

Neo-Lamarckism:

It is an attempted revival of Lamarckism by modifying it and finding evidences for direct effect of environment on germ cells and the effect of somatic cells on germ cells.

Theory of Germplasm:

The theory of germplasm (Weismann, 1892) states that inheritance of characters from parents to offspring is mediated through germplasm which continues generation after generation-hence “THEORY OF CONTINUITY OF GERMPLASM”. The theory is not completely true because somatoplasm can give rise to germplasm as during regeneration and culture experiments because all cells contain the same sets of chromosomes/genes whether they are somatic or germinal.

Darwinism/Theory of Natural Selection:

Darwinism or theory of natural selection is a theory of organic evolution which states that new species evolve over a long period of time through accumulation of small variations which provide the organisms with structural and functional sperioritv over other in their survival and differential reproduction.

Neo-Darwinism:

It is a refinement of original theory of natural selection of remove objections. Mutation Theory

It was given by Hugo de Vries in 1902 in his book Species and Varieties their origin by mutation. He studied the inheritance for seven generations, in Evening Primose (Oenothera lamarckiana). He found that most of the offspring resembled parents but a few variants were not connected with the normal characters by any intermediate form.

The modifica­tions were, therefore, called DISCONTINUOUS variations or sports or mutations. They were inherited. The variants, therefore, produced variants and not normal plant’s. Rather a few variants also developed more variations.

Mutation theory successfully explains progressive and retrogressive evolution, continuation of vestigial and overspecialized organs, struggle for existence and survival of the fittest along with inheritance of useful mutations and formation of new species. A number of mutations have produced new verities, subspecies and even species.

ii. Hornless or Polled Cattle (1889)

Mutations are mostly retrogressive or negative and rate is also very low as compared to requirement of evolutions. It cannot explain origin of certain phenomenon like symbiosis and mimicry.

Genetic Drift:

It is the change in number and frequency of genes in small isolated population due to intensive inbreeding causing permanent fixation of some alleles, disappearance of a number of alleles and change in frequency of others.

It is prevention of mating between otherwise interbreeding groups due to physical and biotic barriers. The barriers allow isolated groups to evolve into distinct populations/varieties/subspecies/ species.

Related posts:

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The Institute for Creation Research

Some people today, especially those of anti-Christian opinions, have the mistaken notion that the Bible prescribes permanent racial divisions among men and is, therefore, the cause of modern racial hatreds. As a matter of fact, the Bible says nothing whatever about race. Neither the word nor the concept of different "races" is found in the Bible at all. As far as one can learn from a study of Scripture, the writers of the Bible did not even know there were distinct races of men, in the sense of black and yellow and white races, or Caucasian and Mongol and Negroid races, or any other such divisions.

The Biblical divisions among men are those of "tongues, families, nations, and lands" (Genesis 10:5,20,31) rather than races. The vision of the redeemed saints in heaven (Revelation 7:9) is one of "all nations, and kindreds, and people, and tongues", but no mention is made of "races". The formation of the original divisions, after the Flood, was based on different languages (Genesis 11:6-9), supernaturally imposed by God, but nothing is said about any other physical differences.

Some have interpreted the Noahic prophecy concerning his three sons (Genesis 9:25-27) to refer to three races, Hamitic, Semitic and Japhetic, but such a meaning is in no way evident from the words of this passage. The prophecy applies to the descendants of Noah's sons, and the various nations to be formed from them, but nothing is said about three races. Modern anthropologists and historians employ a much-different terminology than this simple trifurcation for what they consider to be the various races among men.

Therefore, the origin of the concept of "race" must be sought elsewhere than in the Bible. If certain Christian writers have interpreted the Bible in a racist framework, the error is in the interpretation, not in the Bible itself. In the Bible, there is only one race&mdashthe human race! "(God) hath made of one, all nations of men" (Acts 17:26).

What Is a Race?

In modern terminology, a race of men may involve quite a large number of individual national and language groups. It is, therefore, a much broader generic concept than any of the Biblical divisions. In the terminology of biological taxonomy, it is roughly the same as a "variety", or a "sub-species". Biologists, of course, use the term to apply to sub-species of animals, as well as men.

For example, Charles Darwin selected as the subtitle for his book Origin of Species the phrase "The Preservation of Favoured Races in the Struggle for Life". It is clear from the context that he had races of animals primarily in mind, but at the same time it is also clear, as we shall see, that he thought of races of men in the same way.

That this concept is still held today is evident from the following words of leading modern evolutionist George Gaylord Simpson:

It is clear, therefore, that a race is not a Biblical category, but rather is a category of evolutionary biology. Each race is a sub-species, with a long evolutionary history of its own, in the process of evolving gradually into a distinct species.

As applied to man, this concept, of course, suggests that each of the various races of men is very different, though still inter-fertile, from all of the others. If they continue to be segregated, each will continue to compete as best it can with the other races in the struggle for existence and finally the fittest will survive. Or else, perhaps, they will gradually become so different from each other as to assume the character of separate species altogether (just as apes and men supposedly diverged from a common ancestor early in the so-called Tertiary Period).

Most modern biologists today would express these concepts somewhat differently than as above, and they undoubtedly would disavow the racist connotations. Nevertheless, this was certainly the point-of-view of the 19th century evolutionists, and it is difficult to interpret modern evolutionary theory, the so-called neo-Darwinian synthesis, much differently.

Nineteenth-Century Evolutionary Racism

The rise of modern evolutionary theory took place mostly in Europe, especially in England and Germany. Europeans, along with their American cousins, were then leading the world in industrial and military expansion, and were, therefore, inclined to think of themselves as somehow superior to the other nations of the world. This opinion was tremendously encouraged by the concurrent rise of Darwinian evolutionism and its simplistic approach to the idea of struggle between natural races, with the strongest surviving and thus contributing to the advance of evolution.

As the 19th century scientists were converted to evolution, they were thus also convinced of racism. They were certain that the white race was superior to other races, and the reason for this superiority was to be found in Darwinian theory. The white race had advanced farther up the evolutionary ladder and, therefore, was destined either to eliminate the other races in the struggle for existence or else to have to assume the "white man's burden" and to care for those inferior races that were incompetent to survive otherwise.

Charles Darwin himself, though strongly opposed to slavery on moral grounds, was convinced of white racial superiority. He wrote on one occasion as follows:

The man more responsible than any other for the widespread acceptance of evolution in the 19th century was Thomas Huxley. Soon after the American Civil War, in which the negro slaves were freed, he wrote as follows:

Racist sentiments such as these were held by all the 19th century evolutionists. A recent book 4 has documented this fact beyond any question. In a review of this book, a recent writer says:

A reviewer in another scientific journal says:

The Modern Harvest

In a day and age which practically worshipped at the shrine of scientific progress, as was true especially during the century from 1860 to 1960, such universal scientific racism was bound to have repercussions in the political and social realms. The seeds of evolutionary racism came to fullest fruition in the form of National Socialism in Germany. The philosopher Friedrich Nietzsche, a contemporary of Charles Darwin and an ardent evolutionist, popularized in Germany his concept of the superman, and then the master race. The ultimate outcome was Hitler, who elevated this philosophy to the status of a national policy.

However one may react morally against Hitler, he was certainly a consistent evolutionist. Sir Arthur Keith, one of the leading evolutionary anthropologists of our century, said:

With respect to the question of race struggle, as exemplified especially in Germany, Sir Arthur also observed:

In recent decades, the cause of racial liberation has made racism unpopular with intellectuals and only a few evolutionary scientists still openly espouse the idea of a long-term polyphyletic origin of the different races. 10 On the other hand, in very recent years, the pendulum has swung, and now we have highly vocal advocates of "black power" and "red power" and "yellow power", and these advocates are all doctrinaire evolutionists, who believe their own respective "races" are the fittest to survive in man&rsquos continuing struggle for existence.

The Creationist Position

According to the Biblical record of history, the Creator&rsquos divisions among men are linguistic and national divisions, not racial. Each nation has a distinct purpose and function in the corporate life of mankind, in the divine Plan (as, for that matter, does each individual).

No one nation is "better" than another, except in the sense of the blessings it has received from the Creator, perhaps in measure of its obedience to His Word and fulfillment of its calling. Such blessings are not an occasion for pride, but for gratitude.

References

* Dr. Henry M. Morris (1918-2006) was Founder and President Emeritus of ICR.

Cite this article: Morris, H. 1973. Evolution and Modern Racism. Acts & Facts. 2 (7).


Straw Men Aside, What Is the Theory of Intelligent Design, Really?

Over at Amazon I posted a review of Darwin’s Doubt. The very first commenter on my review, calling himself “Nick,” asked me the question:

What’s the “scientific theory of ID”? Who or what is the designer and how can we tell? What did it do and how can we tell? How did it do it and how can we tell? Where did it do it and how can we tell? When did it do it and how can we tell? Please pass on my thanks to all your colleagues for never bothering to answer these questions.

Given that my Amazon review responded in part to Nick Matzke’s false accusations of errors against Stephen Meyer, I wonder if this is the same “Nick.” It’s not really important. But even though we’ve answered such questions numerous times, they are reasonable things to ask, and as a result I’m more than happy to answer them yet again — not at Amazon for perpetually disgruntled critics, but here at ENV for everyone else to see.

First, let’s discuss what the theory of intelligent design is not.

Part A: What Intelligent Design Is Not
Many critics of intelligent design have promoted false, straw-man versions of ID, typically going something like this:

Intelligent design claims that life is so complex, it could not have evolved, therefore it was designed by a supernatural intelligence.

Of those many ID critics who have promoted this false definition, some know it is a falsehood: I call them “Type I” critics. Others, whom I call “Type II” critics, actually believe the false version to be true but only because they have been misled by Type I critics. Of course it’s not always easy to distinguish the two groups. In the Kitzmiller v. Dover ruling, for example, Judge Jones adopted the plaintiff’s false version of intelligent design — making him, according to my paradigm, a Type II critic, even though ID had been explained to him repeatedly in the courtroom what ID really is. Since Judge Jones knew how ID proponents define their theory, but nonetheless mischaracterized it, does this make him a Type I critic instead? Who can really know?

In any case, there are two main components of this definition, both false:

1. ID is NOT merely a negative argument against evolution
The first problem with the critics’ definition is that it frames ID as merely a negative argument against evolution. In fact, ID offers a strong positive argument, based on finding in nature the type of information and complexity that, in our experience, comes from intelligence alone. I will explain this positive argument further in Part B of this article. Those who claim ID is nothing more than a negative argument against evolution are misrepresenting ID.

2. ID is NOT a theory about the designer or the supernatural
The second problem with the critics’ definition of ID is that it suggests the theory is focused on studying the designer. The claim is that it specifically invokes supernatural forces or a deity. But ID is not focused on studying the actual intelligent cause responsible for life, but rather studies natural objects to determine whether they bear an informational signature indicating an intelligent cause. All ID does is infer an intelligent cause behind the origins of life and of the cosmos. It does not seek to determine the nature or identity of that cause. As William Dembski explains:

Intelligent design is the science that studies signs of intelligence. Note that a sign is not the thing signified. … As a scientific research program, intelligent design investigates the effects of intelligence, not intelligence as such. 1

Similarly, Michael Behe explains that we can detect design even if we don’t know anything about the identity or nature of the designer:

The conclusion that something was designed can be made quite independently of knowledge of the designer. As a matter of procedure, the design must first be apprehended before there can be any further question about the designer. The inference to design can be held with all the firmness that is possible in this world, without knowing anything about the designer. 2

Behe even suggests that “[i]ntelligent design does not require a candidate for the role of the designer.” 3

ID limits its claims to what can be learned from empirical data, meaning that it does not try to address questions about the identity or nature of the designer. While the empirical data allow us to study natural objects and determine whether they arose from an intelligent cause, such data simply may not allow us to determine the identity or nature of the intelligent cause.

One of the earliest works on ID, the textbook Of Pandas and People, explains that ID merely seeks to infer “intelligent causes” and is compatible with a wide variety of religious and nonreligious viewpoints, including pantheism and agnosticism:

The idea that life had an intelligent source is hardly unique to Christian fundamentalism. Advocates of design have included not only Christians and other religious theists, but pantheists, Greek and Enlightenment philosophers and now include many modern scientists who describe themselves as religiously agnostic. Moreover, the concept of design implies absolutely nothing about beliefs normally associated with Christian fundamentalism, such as a young earth, a global flood, or even the existence of the Christian God. All it implies is that life had an intelligent source. 4

The text goes on to explain, “If science is based upon experience, then science tells us the message encoded in DNA must have originated from an intelligent cause. What kind of intelligent agent was it? … We still would not know, from science, if the natural cause was all that was involved, or if the ultimate explanation was beyond nature, and using the natural cause.“ 5

This non-identification of the designer has remained the consistent position of ID proponents throughout its history. For example, William Dembski explains, “Intelligent design is modest in what it attributes to the designing intelligence responsible for the specified complexity in nature. For instance, design theorists recognize that the nature, moral character and purposes of this intelligence lie beyond the competence of science and must be left to religion and philosophy.” 6 Similarly, Michael Behe writes that ID remains silent on questions about whether the designer is natural or supernatural:

[ID] is not an argument for the existence of a benevolent God, as Paley’s was. I hasten to add that I myself do believe in a benevolent God, and I recognize that philosophy and theology may be able to extend the argument. But a scientific argument for design in biology does not reach that far. Thus while I argue for design, the question of the identity of the designer is left open. Possible candidates for the role of designer include: the God of Christianity an angel–fallen or not Plato’s demi-urge some mystical new age force space aliens from Alpha Centauri time travelers or some utterly unknown intelligent being. Of course, some of these possibilities may seem more plausible than others based on information from fields other than science. Nonetheless, as regards the identity of the designer, modern ID theory happily echoes Isaac Newton’s phrase hypothesis non fingo. 7

Some critics allege that ID proponents are “coy” about the identity of the designer, who they really believe is God. Yet major ID proponents in all the cases I’m aware of have been quite open about their own views as to the identity of the designer — they have simply made it clear that these are personal beliefs, perhaps with philosophical or historical justifications, but not conclusions of science. For example, Michael Behe explains:

[M]ost people (including myself) will attribute the design to God — based in part on other, non-scientific judgments they have made — I did not claim that the biochemical evidence leads ineluctably to a conclusion about who the designer is. In fact, I directly said that, from a scientific point of view, the question remains open. … The biochemical evidence strongly indicates design, but does not show who the designer was. 8

When ID proponents say that ID does not identify the designer, they are, in Behe’s words, “only limiting … claims to what … the evidence will support.” 9 During the Kitzmiller trial, Behe gave clear, direct, and unambiguous testimony on this topic:

Q. So is it accurate for people to claim or to represent that intelligent design holds that the designer was God?

Behe: No, that is completely inaccurate.

Q. Well, people have asked you your opinion as to who you believe the designer is, is that correct?

Behe: That is right.

Q. Has science answered that question?

Behe: No, science has not done so.

Q. And I believe you have answered on occasion that you believe the designer is God, is that correct?

Behe: Yes, that’s correct.

Q. Are you making a scientific claim with that answer?

Behe: No, I conclude that based on theological and philosophical and historical factors. 10

Similarly, Phillip Johnson writes, “My personal view is that I identify the designer of life with the God of the Bible, although intelligent design theory as such does not entail that.” 11 As for myself, I too believe the designer is the God of the Bible, but this is not a conclusion of ID it is my personal religious view that stems from factors quite apart from intelligent design.

The refusal of ID proponents to use ID to draw conclusions about the nature or identity of the designer is principled rather than merely rhetorical. Simply put, there is no known scientific method for identifying the intelligent source responsible for design in nature. While the information in DNA points to an intelligent cause, that information by itself cannot scientifically tell you whether the intelligence is Jehovah, Allah, Buddha, Yoda, or some other intelligent source.

Since ID is based solely upon empirical data, it must remain silent on such questions. ID respects the limits of scientific inquiry, and thus refuses to inject discussions about theological questions into science. Stephen Meyer explains:

Though the designing agent responsible for life may well have been an omnipotent deity, the theory of intelligent design does not claim to be able to determine that. Because the inference to design depends upon our uniform experience of cause and effect in this world, the theory cannot determine whether or not the designing intelligence putatively responsible for life has powers beyond those on display in our experience. Nor can the theory of intelligent design determine whether the intelligent agent responsible for information in life acted from the natural or the “supernatural” realm. Instead, the theory of intelligent design merely claims to detect the action of some intelligent cause (with power, at least, equivalent to those we know from experience) and affirms this because we know from experience that only conscious, intelligent agents produce large amounts of specified information. The theory of intelligent design does not claim to be able to determine the identity or any other attributes of that intelligence, even if philosophical deliberation or additional evidence from other disciplines may provide reasons to consider, for example, a specifically theistic design hypothesis. 12

ID is primarily a historical science, meaning it uses principles of uniformitarianism to study present-day causes and then applies what it has learned to examine the historical record. It does so in order to infer the best explanation for the origin of the natural phenomena being studied. As Pandas explains, scientists have “uniform sensory experience” 13 with intelligent causes (e.g., humans), thus making intelligence an appropriate explanatory cause within historical scientific fields. However, the “supernatural” cannot be observed. Thus historical scientists applying uniformitarian reasoning cannot appeal to it. Even if the intelligence responsible for life is indeed supernatural, science could only infer the prior action of intelligence, but could not determine whether the intelligence was supernatural. 14

But there are other common misconceptions about what ID is.

3. ID is NOT a theory of everything
ID is a scientific theory of design detection, that’s all — not a full-blown theory of everything. It focuses on how we can detect the working out of purpose in biology, physics, cosmology, and other scientific fields.

Anyone expecting or demanding that intelligent design should explain everything that happened in the history of life and the cosmos will be disappointed. That’s not what ID was intended to be. If you want to find out how old a rock is, ask a geologist. If you want to know how old a star is, consult experts in the field of astronomy or cosmology. Those fields provide perfectly good answers to such questions. But if you want to know whether something was designed or not, turn to the study of intelligent design.

If you demand that advocates of the “theory of ID” give you a full chronology of everything, you’re asking the wrong question of the wrong people just as much as if you asked theorists of neo-Darwinism for such a chronology.

Part B: What the Theory of Intelligent Design Is
Intelligent design is a scientific theory that argues that the best explanation for some natural phenomena is an intelligence cause, especially when we find certain types of information and complexity in nature which in our experience are caused by intelligence.

1. ID uses a positive argument based upon finding high levels of complex and specified information
The theory of intelligent design begins with observations of how intelligent agents act when they design things. Human intelligence provides a large empirical dataset for studying the products of the action of intelligent agents. This present-day observation-based dataset establishes cause-and-effect relationships between intelligent action and certain types of information.

William Dembski observes that “[t]he principle characteristic of intelligent agency is directed contingency, or what we call choice.” 15 Dembski calls ID “a theory of information” where “information becomes a reliable indicator of design as well as a proper object for scientific investigation.” 16 A cause-and-effect relationship can be established between mind and information. As information theorist Henry Quastler observed, the “creation of new information is habitually associated with conscious activity.” 17

The most commonly cited type of “information” that reliably indicates design is “specified complexity.” As Dembski writes, “the defining feature of intelligent causes is their ability to create novel information and, in particular, specified complexity.” 18 Though the terms were not originally coined by an ID proponent, Dembski suggests that design can be detected when one finds a rare or highly unlikely event (making it complex) which conforms to an independently derived pattern (making it specified). ID proponents call this complex and specified information, or “CSI.” Stephen Meyer explains that in our experience, only intelligent agents produce this type of information:

“Agents can arrange matter with distant goals in mind. In their use of language, they routinely ‘find’ highly isolated and improbable functional sequences amid vast spaces of combinatorial possibilities.” 19
“[W]e have repeated experience of rational and conscious agents — in particular ourselves — generating or causing increases in complex specified information, both in the form of sequence-specific lines of code and in the form of hierarchically arranged systems of parts. … Our experience-based knowledge of information-flow confirms that systems with large amounts of specified complexity (especially codes and languages) invariably originate from an intelligent source, from a mind or personal agent.” 20

By assessing whether natural structures contain the type of complexity — high CSI — that in our experience comes only from intelligence, we can construct a positive, testable case for design. And what happens when we study nature? Well, the past sixty years of biology research have uncovered that life is fundamentally based upon:

  • A vast amount of complex and specified information encoded in a biochemical language.
  • A computer-like system of commands and codes that processes the information.
  • Molecular machines and multi-machine systems.

But where in our experience do things like language, complex and specified information, programming code, or machines come from? They have one and only one known source: intelligence. When we look at nature, we find high levels of CSI. A design inference may thus be made. This is the essence of the positive case for design.

2. Intelligent Design is a historical science that is methodologically equivalent to neo-Darwinism
As we saw already, intelligent design is primarily a historical science, meaning it studies present-day causes and then applies them to the historical record to infer the best explanation for the origin of natural phenomena. Intelligent design uses uniformitarian reasoning based upon the principle that “the present is the key to the past.”

Darwinian evolution applies this method by studying causes like mutation and selection in order to recognize their causal abilities and effects in the world at present. Darwinian scientists then try to explain the historical record in terms of those causes, for example seeking to recognize the known effects of mutation and selection in the historical record.

Intelligent design applies this same method by studying causes like intelligence in order to recognize its causal abilities and effects in the present-day world. ID theorists are interested in understanding the information-generative powers of intelligent agents. ID theorists then try to explain the historical record by including appeals to that cause, seeking to recognize the known effects of intelligent design (e.g., high CSI) in the historical record.

So whether we appeal to materialistic causes like mutation and selection, or non-material causes like intelligent design, we are using the same basic uniformitarian reasoning and scientific methods that are well-accepted in historical sciences. ID and neo-Darwinism are thus methodologically equivalent, meaning that either both are science, or both aren’t science. However, we can know that ID is science because it uses the scientific method.

3. Intelligent design uses the scientific method
ID uses the scientific method to make its claims. This method is commonly described as a four-step process of observations, hypothesis, experiments, and conclusion. I now will illustrate this by referring to four scientific fields: biochemistry, paleontology, systematics, and genetics.

  • ID and Biochemistry:
    Observation: Intelligent agents solve complex problems by acting with an end goal in mind, producing high levels of CSI. In our experience, systems with large amounts of specified complexity — such as codes and languages — invariably originate from an intelligent source. Likewise, in our experience, intelligence is the only known cause of irreducibly complex machines. 21
    Hypothesis (Prediction): Natural structures will be found that contain many parts arranged in intricate patterns (including irreducible complexity) that perform a specific function — indicating high levels of CSI.
    Experiment: Experimental investigations of DNA indicate that it is full of a CSI-rich, language-based code. Biologists have performed mutational sensitivity tests on proteins and determined that their amino acid sequences are highly specified. 22 Additionally, genetic knockout experiments and other studies have shown that some molecular machines, like the flagellum, are irreducibly complex. 23
    Conclusion: The high levels of CSI — including irreducible complexity — in biochemical systems are best explained by the action of an intelligent agent.
  • ID and Paleontology:
    Observation: Intelligent agents rapidly infuse large amounts of information into systems. As four ID theorists write: “intelligent design provides a sufficient causal explanation for the origin of large amounts of information … the intelligent design of a blueprint often precedes the assembly of parts in accord with a blueprint or preconceived design plan.” 24
    Hypothesis (Prediction): Forms containing large amounts of novel information will appear in the fossil record suddenly and without similar precursors.
    Experiment: Studies of the fossil record show that species typically appear abruptly without similar precursors. 25 The Cambrian explosion is a prime example, although there are other examples of explosions in life’s history. Large amounts of complex and specified information had to arise rapidly to explain the abrupt appearance of these forms. 26
    Conclusion: The abrupt appearance of new fully formed body plans in the fossil record is best explained by intelligent design.
  • ID and Systematics:
    Observation: Intelligent agents often re-use functional components in different designs. As Paul Nelson and Jonathan Wells explain: “An intelligent cause may reuse or redeploy the same module in different systems … [and] generate identical patterns independently.” 27
    Hypothesis (Prediction): Genes and other functional parts will be commonly re-used in different organisms. 28
    Experiment: Studies of comparative anatomy and genetics have uncovered similar parts commonly existing in widely different organisms. Examples of “extreme convergent evolution” show re-use of functional genes and structures in a manner not predicted by common ancestry. 29
    Conclusion: The re-use of highly similar and complex parts in widely different organisms in non-treelike patterns is best explained by the action of an intelligent agent.
  • ID and Genetics:
    Observation: Intelligent agents construct structures with purpose and function. As William Dembski argues: “Consider the term ‘junk DNA.’ … [O]n an evolutionary view we expect a lot of useless DNA. If, on the other hand, organisms are designed, we expect DNA, as much as possible, to exhibit function.” 30
    Hypothesis (Prediction): Much so-called “junk DNA” will turn out to perform valuable functions.
    Experiment: Numerous studies have discovered functions for “junk DNA.” Examples include functions for pseudogenes, introns, and repetitive DNA. 31
    Conclusion: The discovery of function for numerous types of “junk DNA” was successfully predicted by intelligent design.

In this way, we can see that intelligent design is a bona fide scientific theory that uses the scientific method to make its claims in multiple scientific fields.

Concluding Thoughts
This article has discussed what the theory of intelligent design isn’t, and what it is:

  • It isn’t merely a negative argument against evolution.
  • It isn’t an argument for the supernatural, nor is it even focused on studying the designer.
  • It isn’t a theory of everything.
  • It is a positive argument based upon finding high levels of complex and specified information
  • It is a historical science that uses uniformitarian reasoning based upon the principle that “the present is the key to the past.”
  • It is methodologically equivalent to neo-Darwinism, such that ID and neo-Darwinism are both bona fide scientific theories.
  • It is a science that uses the scientific method to make scientific claims in fields such as biochemistry, paleontology, genetics, and systematics.
  • It is a scientific theory that argues that the best explanation for some natural phenomena is an intelligence cause, especially when we find certain types of information and complexity in nature which in our experience are caused by intelligence.

Critics may continue to pretend I have not explained what the theory of intelligent design is. But they will not convince those with an open mind who have read this article.


Watch the video: Theory of Evolution: How did Darwin come up with it? - BBC News (August 2022).