Re. Endogenous Retroviruses and Evolution (Modern Synthesis)

On an article from "Apologetics Central"

The text from the original article is reproduced in black.

My comments are rendered in red.

This article’s purpose is to provide a high-level overview of the relationship between ERVs and neo-Darwinian evolution. All cited papers are referenced. Visit the websites and papers listed in references if you require more in-depth knowledge.

What is an ERV?

Perhaps the most famous retrovirus is the Human Immunodeficiency Virus (HIV). Normal viruses work by invading a cell’s DNA and taking the cell’s organelles (the tiny cellular structure that performs specific functions within a cell) for its own use. Now, a retrovirus, unlike a normal virus (which just invades the cell), actually inserts DNA into the genome of the cell it infects, altering the cell’s DNA structure. Once the exogenous (meaning it originates from a source outside the body) retrovirus infects the host by inserting DNA, it uses the host cell’s machinery to create more viruses, thereby infecting other cells. When the exogenous retrovirus infects an egg- or sperm cell, the viral DNA is passed down to the offspring of the host and the virus becomes an endogenous retrovirus (ERV).

So far so good. Many creationists deny that endogenous retroviruses even exist, or that they are capable of integrating their DNA with the DNA of germ-line cells.
These viral genomes (viral genomes are genes that are infected with the viral DNA of the ERV) are very susceptible to mutation. Any mutations that prevents a virus from performing its function renders the virus useless, as its entire genome is broken. The catch is that DNA added by a retrovirus remains present at the same loci (locus) (place) in the host organism as “junk DNA” (DNA that does not code for a protein and does not seem to serve any useful purpose). So, endogenous retroviruses in this context are thought to be pieces of DNA found in an organism’s genome that looks like a retroviruses, but actually does not code for anything. ERVs also have particular DNA sequences that molecular biologists can use to identify them. The following video gives insight into how retroviruses function. Notice the intricate molecular machines at work. These molecular machines are pre-supposed to be in place by the ERV argument for Darwinian evolution, with no explanation presented for how these machines could have developed by pure naturalistic processes. It is almost as if the machines at work for these ERVs to insert, are evidence of design itself and uproot the common ancestry hypothesis that neo-Darwinists are trying to prove by referencing them.

No. A viral genome is the sequence of base-pairs (either in RNA or DNA form) that "specifies" the complete virus. Retroviral genomes are indeed very susceptible to mutation, particularly during reverse transcription, when their RNA genomes are converted to DNA versions (proviruses), in preparation for integration with the host genome.

Retroviral DNA remaining present at the same locus does code for proteins. (The replication cycle of a retrovirus requires many proteins). Retroviral promoters are also essential, otherwise, the retrovirus will not be transcribed.

Endogenous retroviruses are merely retroviral integrations into germ-line cells. They are not necessarily all composed of "junk". They are most likely to contain mutations that prevent the retrovirus from completing its full replication cycle because a zygote inheriting any replication-competent provirus is very unlikely to be viable and able to pass on its genetic burden, but not all of the retroviral DNA of every ERV is necessarily inactivated.

The assertion that 'evolutionists'* insist that all endogenous retroviral DNA is "junk" is a falsehood that has been repeated and corrected so many times (it is real scientists who have discovered still-functional and exapted components of ERVs), that it can safely be described as a deliberate lie.

How do ERV's Evidence Darwinian Evolution?

Suppose an organism obtains one of these ERVs and passes the gene with the altered DNA onto its offspring. Somewhere along the line one of the offspring breaks the viral gene rendering it useless through a mutation (as discussed in the previous section). The offspring has a gene that doesn’t affect anything (“junk DNA”) but it is still present in its DNA. Molecular biologists can identify these DNA sequences as ERVs.

An ERV that has not mutated beyond recognition is easily identified as being of retroviral origin. Again, some genes and promoters are disabled by mutation, but not necessarily all. "Junk" can be, and is, recycled.

All of the offspring of that ancestor have a copy of that gene, and more importantly, the gene exists in the same relative place (loci) (locus) within the DNA. As time goes on and species diverge into new species this gene will persist, according to Neo-Darwinians. Thus, all animals with this gene will have to share common descent as this could be the only explanation to why they all have this gene in the same place.

Some of the offspring will have a copy of, not "that gene", but of ancestral retroviral genetic sequences, but not necessarily all, unless the ERV has gone to fixation in the species. This is quite an important point, which will be significant when we come to discuss incomplete lineage sorting.

Studies have found that humans and other great apes like the chimpanzee all share the certain ERV sequence containing “junk DNA” (1). This led Neo-Darwinians to conclude that this ERV sequence is evidence of a common ancestor between humans and chimps. To be precise, 14 of the 98000 ERVs in the human genome are found in the same location as in chimps.

Actually, the figure is all but a few hundred ERVs among 100,000 to 200,000 orthologous ERVs and ERV fragments common to both species! I'll come back to discuss the origin of the pre-genome sequencing 14/98,000 boob later.

If the common descent theory does not hold we would not see a relationship between shared ERVs and the closeness of two species. The more closely related two organisms, the more ERVs they share, or so Neo-Darwinians assume.

Note that it is shared ERVs corresponding loci that is significant for common descent. Shared ERVs in differing locations are evidence for horizontal, not vertical (inherited) transfer. This is an important point that will come up later.

Answering the Objection - what 'objection'?

Until recently, Christians (creationists! Don't hide behind the "Christian" label.) argued that common ancestry could be interpreted as evidence of common design. This is similar to saying that since all of Audi’s cars look alike, they are likely to have a common designer. In the same way we could use the fact that almost all animals have eyes to argue that they were likely designed by a common designer. The common design argument is countered by the ERV argument, since if the ERV argument holds, common ancestry would be the only possible explanation as to why we all share this defunct DNA sequence in our genome.

Observe closely that the Evolutionist’s* argument is built around the fact that the ERV infected genome contains junk DNA that serves no purpose.If we can prove that ERVs aren't junk, but are a type of functional DNA, then shared ERVs would easily be explained by common design rather than common descent. ERV’s would then no longer be a special argument for common ancestry. Thus it can be argued that the ERVs are intrinsic genetic elements and not genuine inserts into the DNA, as the DNA sequences perform a function.

Here is the lie again. A deliberately made straw-man argument is an act of deception that no real Christian would indulge in. The argument from common descent rests on the fact that ERVs are evidently of retroviral origin, and that multitudes of ERVs in corresponding DNA loci in more than one species is only explicable by common inheritance. It has nothing whatsoever to do with whether or not there are endogenous retroviral elements that perform any functions.

If the ERVs are found to have a function, it is highly unlikely that these sequences were inserted by retroviruses, as functional ERVs would depend highly on their position and sequence. If they were positioned slightly wrong or had the wrong sequence, they wouldn’t be functional. Viruses do not randomly insert tens of thousands of ERVs which just happen to be in the right location, having the right sequence to perform some valuable function.

Repeat a lie a thousand times, and it becomes the truth, right? Regarding location, other than being within reach of control elements (which retroviral genes always are), the position of genetic material has no effect on its operation. To think that it does betrays a basic misunderstanding of how genetics works.

Thus for these DNA sequences to be viewed as defunct ERVs, it is of extreme importance to the neo-Darwinian argument that they do not have any function.

Three strikes (or was it four?) and out.

Another problem for the hypothesis that the ERVs are inserted is the process of apoptosis:

“Apoptosis, or programmed cell death, is a normal component of the development and health of multicellular organisms. Cells die in response to a variety of stimuli and during apoptosis, they do so in a controlled, regulated fashion. The latter occurs when T-cells recognize damaged or virus infected cells and initiate apoptosis in order to prevent damaged cells from becoming neoplastic (cancerous) or virus-infected cells from spreading the infection.” (18) Thus we would expect apoptosis, which is programmed cell death, to kill most of the ERV-containing cells. Interestingly, we observe that humans still have approximately 98000 of these sequences. Surely apoptosis would have eliminated the majority of them, had they been inserted by retroviruses.

The writer has already admitted that retroviral replication is very error-prone. The stimulus is not necessarily there every time. Indeed, where it is not, these are the ERVs that will survive to go on to be reproduced. Consider, also, apoptosis inhibitors. These are genes (that the writer tries to insist without evidence cannot exist in ERVs) that retroviruses commonly sport.

In a study “Proliferation of Endogenous Retroviruses in the Early Stages of a Host Germ Line Invasion”, Dr. Alfred L. Roca discovered that in order to end up with 100 ERVs in an organism, you need the ancestor the begin with 10 000 ERVs. (17) By applying this to our genome, and assuming the relationship between the proportions are linear, in order for us to end up with 98 000 ERVs, the common ancestor had to have 9800 000 ERVs. Meaning 800% more viral information.

This is just silly. ERVs can accumulate in genomes generation upon generation, in different individuals. Study the spread of endogenous KoRV, with its multiple integrations of KoRV retroviruses. 

Understanding the ERV Structure

The accompanying diagram shows three significant protein-coding genes called pol, env, and gag. In addition to these, the retroviruses are characterized by the LTR (long terminal repeat sequences) at the ends. These LTR sequences can be thought of as a control center for gene expression. The LTRs each contain two unique non-protein-coding sequences, called U5 and U3, which are responsible for encoding particular controlling elements.

Are the ERV's Functional?

Over the past few years, scientists found numerous different functions for the components of the ERV, rendering them no longer junk DNA:

Not this straw-man yet again! Nobody claims that all retrovirally-derived genomic material is non-functional!

One example is at the LTR ends of the retroviral genome are now known to contribute to the host organism’s promoters (4, 5) (Promoters are DNA sequences whose purpose is not to encode information about the organism itself, but rather they serve as a kind of "On" switch to initiate the biological process of transcription for the genes which follow the promoter DNA sequence (3)).

This is a gross oversimplification of the exogenous transcription networks, but OK. Drop promoter at random into the genome, and what is it going to do. Either nothing, or it will regulate, however indirectly, the transcription of adownstream protein-coding gene complex. The effects of this will be subject to natural selection (already acknowledged as a real phenomenon by the writer in his/her comments above). What is the mystery here?

It is also reported that the MuERV-L (Murine Endogenous Retrovirus, a form of ERV) plays a very important role in the development of mouse one-cell embryos, and that was the in the cases where the MuERV-L was removed, the embryo could not develop at all. The embryogenesis (the formation and development of an embryo) literally grinds to a halt. (6)

Yes. Adaptive effects of ERV genetics are preserved by evolution. Is this an example of the old canard "irreducible complexity"? I hardly see any reason to believe so. 

There is also now a growing wealth of literature documenting the role of ERVs in conferring immunity to their host from infection by exogenous retroviruses (these are infectious RNA-containing viruses which are transmitted from human to human (horizontal transmission, meaning the transmission of infections between members of the same species that are not in a parent-child relationship). Talking from an evolutionary viewpoint, Harmit S. Malik and Steven Henikoff wrote the following on the ERV they renamed Iris: “We propose a model in which Iris has “switched sides,” having been recruited by host genomes to combat baculoviruses and retroviruses, which employ homologous envelope genes to mediate infection.” (7)

Hardly surprising. Retroviruses are in evolutionary competition with one another. The ones that can resist invasion by other retroviruses will be the ones that persist in our genomes.

There have been more complex uses found for the ERV that inserted themselves in our genomes previously regarded as “junk”. As a final example you can take a look at the paper “Syncytin-A and syncytin-B, two fusogenic placenta-specific murine envelope genes of retroviral origin conserved in Muridae” published in the PNAS (Proceedings of the National Academy of Sciences), volume 102 issue 2.

How many times has the lie that "evolutionists"* believe that all retroviral genomic material is "junk" been repeated now? I've lost count. I refer the reader to my page on syncytins. 

Thus we can safely conclude that the ERV’s are far from junk DNA, but in many cases serve a very important function.

We all know that, thanks to the work of actual scientists.

“ENCODE” Data Shows that ERVs are not Junk DNA ENCODE DATA: Encyclopedia of DNA Elements.

No, it does not.

There is good evidence that ERVs as a class of DNA is functional. A 2013 paper in PLOS Genetics (8) using ENCODE data reported that very high percentages of endogenous retroviruses in the human genome are associated with open chromatin (Chromatin is a complex of macromolecules found in cells, consisting of DNA, protein, and RNA) and that they are transcribed non-randomly, suggesting some functional role:

You are repeating yourself here. These aspects have been discussed above.

Although emerging evidence suggests that transposable elements (TEs) have contributed novel regulatory elements to the human genome, their global impact on transcriptional networks remains largely uncharacterized. Here we show that TEs have contributed to the human genome nearly half of its active elements. Using DNase I hypersensitivity data sets from ENCODE in normal, embryonic, and cancer cells, we found that 44% of open chromatin regions were in TEs and that this proportion reached 63% for primate-specific regions.

We also showed that distinct subfamilies of endogenous retroviruses (ERVs) contributed significantly more accessible regions than expected by chance, with up to 80% of their instances in open chromatin. Based on these results, we further characterized 2,150 TE subfamily-transcription factor pairs that were bound in vivo or enriched for specific binding motifs and observed that TEs contributing to open chromatin had higher levels of sequence conservation.

We also showed that thousands of ERV-derived sequences were activated in a cell type-specific manner, especially in embryonic and cancer cells, and we demonstrated that this activity was associated with cell type-specific expression of neighboring genes. Taken together, these results demonstrate that TEs, and in particular ERVs, have contributed hundreds of thousands of novel regulatory elements to the primate lineage and reshaped the human transcriptional landscape.

ERVs are being transcribed in a highly non-random manner that correlates with embryological patterns in association with other functional genetic elements. This decidedly points towards functionality. If they are functional, then they don’t provide any kind of special evidence for common ancestry.

What are you trying to get at here? That advantageous DNA modifications are advantageous?

But Functional ERVs Will Kill You? Abbie Smith in her blog ‘ERV’ writes: “If I've said it once, I've said it 1,000 times– You do not want ERVs to be functional. Functional ERVs would be ‘endogenous proviruses’, thus they could kill you. Even though the most ‘popular’ retrovirus, HIV-1, doesn’t cause cancer, cancer is retroviruses favorite trick! B-cell leukemias, T-cell lymphomas, erythroleukemia, myeloid leukemias, osteosarcomas, fibrosarcomas, carcinomas… No one, including design proponents, want ERVs to be functional!” (12)

Yes. Retroviruses are often associated with cancer. And?
This is true. When we find that these supposed ‘Junk DNA’ sequences (that theoretically came from ERVs) are in fact functional and benefits the organism containing them, they are not ERV sequences but intrinsic genetic elements (meaning they were there from the beginning).

Unsupported assertion. We are getting pretty desperate here.

Putting the Objection to Rest

The reason neo-Darwinists look at the ERVs that are found in the same place (loci) and ascribe it to common descent is a product of the miniscule probability that a retrovirus will insert itself into the genome at the same place in multiple independent lineages or species. For example, all the great apes, humans and other mammals which share this junk DNA in their genome must have been independently infected in the same place on different occasions if they are not from common descent. This probability is very small, or so they believe. It is so unlikely, that if it was not through common descent, it could make a strong case for intelligent design, which is why Darwinists postulate a single infection somewhere in the past passed down to the current generation.

You seem to be beginning to understand this.

But, as we have shown, the ERVs are not necessarily junk DNA when viewed in the context of other evidence (such as that from embryology), which as uncommondescent.com states clearly militates against common descent. The reason many mammals have the same beneficial ‘ERV’ DNA strand in their genome can point to a common designer in the same way most animals exhibit two eyes: It works. To postulate a common designer must at the very least be taken with the same or more credibility as a common ancestor as the theory of evolution heavily lacks any feasible method to create by blind and mindless processes the very intricate machines we find in the biological world today. Hence we have strong evidence that ERVs weren’t the product of retroviruses, but intrinsic genetic elements.

What is the "strong evidence" that ERVs were the product of intrinsic genetic elements? We never get to see this supposed "evidence".

Could the ERV Insert in Any Place?

We have now seen that ERVs can equally well be explained by common descent or a common designer. We now consider a different viewpoint: Let’s concede the neo-Darwinism’s science stopping view (discussed further in the conclusion) that the ERVs are junk and serve no purpose to the host whatsoever.

Evolutionary biologist Richard Sternberg gave a student the following response when queried on the role ERVs play in common descent. Sternberg uses the fact that the ERV could have inserted independently due to constraints on integration (it is the best or only place the ERV could insert in independent infections). (Source: Sternberg)

“Now, the story that these seemingly defunct retroviruses provide compelling evidence for common descent on the one hand, and support for the notion of non-designed junk on the other, is based on an interpretation that is almost thirty years old and contradicted by recent data. For one thing, ERVs are markedly taxon-specific and they all have non-random chromosomal distributions. The mouse and rat have different ERV families and yet many of them occupy similar genomic sites. This is explained by the insertion machinery having preferences for specific DNA targets or chromatin profiles. So while one can find some retroviral sequences occupying a position shared between by two species, it cannot be ruled out that such similarity is due to constraints on integration. In yeast, for example, the ERV Ty repeatedly inserts into the promoters of transfer RNA genes. And human and mouse “jumping genes” such as Alu and B1/B2, respectively, are not homologous and yet that has the same linear pattern of placement. Such genomic profiles look like inherited accidents from afar but close inspection reveals that they are independent events. Appearances can be deceiving.

I could continue in this vein for some time. My point is that a tenebrific/dark spin has been given to ERVs by the Darwinians. The spin works only as long as one superficially reviews old literature. But it dissipates as soon as one delves into the wealth of data that we now have available to us.”

It becomes clear that some experts feel that the most recent literature contradicts the idea that these ERVs prove common descent. This idea of common descent can only only hold when we review scientific literature that is over 30 years old. Let’s see if this is the case (10):

Similar integration sites doesn't cut it. Wa are talking about base pair level resolution in integration sites in different species. As specific as you can get. Hundreds of thousands of them. 

In an article titled “Three Layers of Endogenous Retroviral Evidence for the Evolutionary Model”, under a section called “Creationist responses” it is claimed that the ERV insertion is not locus specific, which implies that insertion of the ERV into the genome is highly random (it could have inserted anywhere in the genome), and the fact that it is found in the same place (loci) in many mammals must point to a common ancestor. What do other studies show?

A study in 2001(13) shows that an HERV-K is present in the same place in the gorilla and chimpanzee genomes, but not in the human genome. Humans still contain an intact pre-integration site at this locus (the pre-integration complex (PIC) is a nucleoprotein complex of viral genetic material and associated viral and host proteins which are capable of inserting a viral genome into a host genome). The intact pre-integration site in humans removes the possibility of the HERV-K having been inserted into the genome of a common ancestor of humans, chimpanzees, and gorillas, and suggests that an independent insert in the chimpanzee and gorilla genome may be the most plausible explanation. There may be other hypotheses on why we observe this, but in light of these studies, we can conclude that the inserts happened independently.

Independent inserts are not evidence for common ancestry. Indeed, they are evidence for horizontal transfer. But so what?

A 1998 study by Eugene D. Sverdolv described the integration specificity and distribution of the HERVs and LTRs in the human genome and discusses possible functional consequences of their integration in the vicinity of genes (14). To quote from the study:

“But although this concept of retrovirus selectivity is currently prevailing, practically all genomic regions were reported to be used as primary integration targets, however, with different preferences. There were identified `hot spots' containing integration sites used up to 280 times more frequently than predicted mathematically. A recent study of the de novo retroviral integration demonstrated also a preference for scaffold- or matrix-attachment regions (S/MARs) flanked by DNA with high bending potential.” A 2005 study (16) by M.K Lewinski showed:

“Different retroviruses have clear preferences for integration in or near particular chromosomal features... Research into the mechanisms of retroviral integration site selection has shed light on the phenomena of insertional mutagenesis and viral latency." This makes it clear that the ERV does not insert itself anywhere in the genome, but that there are different places it would prefer to insert, increasing the probability of independent infections, and reducing the strength of the common ancestor ‘necessity’ to explain the similar positions of the ERV genomes.

280 times more likely is insufficient to explain precise common integration sites in thousands of cases. A little aquaintence with mathematics, esp. probability theory should convince anyone but a fanatic of the truth of this.

More on this topic can be read here: Evolution News

Evolution News writes: Why might these ERV site-preferences exist? Presumably, because these sites are most conducive to their successful reproduction. Out of tens of thousands of ERV elements in the human genome, roughly how many are known to occupy the same sites in humans and chimpanzees? According to Talk-Origins (15), at least seven. Let’s call it less than a dozen. Given the sheer number of these retroviruses in our genome (literally tens of thousands), and accounting for the evidence of integration preferences and site biases which I have documented above, what are the odds of finding a handful of ERV elements which have independently inserted themselves into the same locus? The answer to the question is clear, it is incredibly large. Gorillas and Chimpanzees have ERV sequences not present in humans, humans have ERV sequences not present in chimps and gorillas and the combinations go on. There are tens of thousands of ERV elements in the human genome. The probability that we share the same sequence with the great apes is quite high given the integration preference we discussed above combined with the many sequences present. A common ancestor is a very unnecessary and complicated theory to develop when presented with the new evidence.

See above.

Conclusion

Evolutionists* have accused proponents of the intelligent design theory of being ‘science stoppers’ yet this is ironic when labeling findings in our genome as ‘junk DNA’. It seems as though their a priori commitment to naturalism and hence evolution has led them to expect to find junk DNA in nature. When they find DNA sequences that at first glance seem to serve no function, they simply hop on the train as if to say, “There we go, junk DNA that does absolutely nothing: evidence for darwinian evolution!”. Proponents of intelligent design believe that as we are designed, we would at least expect most of our genome to have some sort of function, which incidentally seems to be the case when we review the latest research regarding the human genome.

Remember that killing machines like viruses were not part of God’s creation. All life, including life on the molecular level, were good. After the fall of Adam and Eve, good machines became degenerate and unable to perform their original function.

Evidence?

It is for this reason that the human genome is much less pure than our ancestors three thousand years ago when God allowed brother and sister to marry. We have seen that some ERVs allow the host to thrive. Now the question is: Why does a ‘retrovirus’ have to become part of the host to begin helping, as opposed to just being there from the beginning? Genetic entropy is at work in this world, meaning good DNA sequences stop working correctly. It is not hard to postulate that some these ‘ERV’ sequences were in fact originally part of the genome that has deteriorated over time.

Evidence?

We conclude that evolution as evidence that God is not needed is at its core flawed. The naturalist assumes that God doesn’t exist, and then constructs a theory that tries to explain natural occurrences as best he can without God. He then proceeds to claim he has proved God doesn’t need to exist. The problem is that the theory will show no need of God if that is the assumption that was started with.

Who are "we"? This garbage is disproven by the fact that many theists accept evolution and the evidence that ERVs are a powerful confirmation that evolution is true. It is dishonest (there is a theme here) to imply that following the facts and applying basic reason is motivated by a desire to disprove gods.


For example when proving something mathematically, initial assumptions are required from which the rest of the reasoning follows logically. If A, then B. It could happen that the mathematician gets lost in a proof and then arrive back at the initial assumptions, meaning they came full circle. If A, then A. This circular reasoning does not contribute to what is in the process of being proved.

Science is not an axiomatic system like mathematics. It rests on evidence and reasoning applied to the evidence, as exemplified by this FAQ. 

But doesn’t this apply to Intelligent Design as well? Don’t its adherents also presuppose the existence of a creator? The Intelligent Design movement is based on the common observation that design implies a designer. There is no need to presuppose the existence of one for that observation to be made. The intelligent design theory can be formulated like this (by lending from “The Fundamentals of Mathematical Analysis (19), theorem 2.1.1, example of proof by contradiction):

If it is assumed that a result (a Designer exists) is false, it can be shown that this assumption is inconsistent with the given information, meaning no natural process can account for the complexity of life today. Since it is then possible to deduce inconsistencies from assumed true statements, the original assumption must be false. The required result that a Designer exists is then, in fact, true.

Argument from personal incredulity.
In our opinion, the theory of Darwinian evolution lacks. It cannot describe or provide sufficient reasons for us to believe that random mindless processes can create the intricate machines we see in nature today. ERVs which were dubbed as the best proof of evolution 30 years ago, is no longer valid today as recent studies show. Intelligent Design stays on top as the only viable explanation for our experiences in the biological world today. It is important to note that the whole concept of evolution should not be rejected. Mutations and natural selection exist but it doesn’t possess the magical powers neo-Darwinians claim.

Ah. I can see where the personal incredulity comes from - the usual straw-man version of evolution. Intricate machines are not created by "random mindless processes", but by the selection of advantageous heritable variations. But I can see the attraction in attacking a straw-man version of the theory. It reassures the gullible.

*Google defines "evolutionist" as, "a person who believes in the theories of evolution and natural selection". Virtually nobody believes in these theories, rather, they are concluded on the basis of evidence and reason.
(References to be found in the original piece.)

*"Evolutionism"Creationist propaganda frequently uses the word "evolutionist". Here is Google's definition of "evolutionist".nouna person who believes in the theories of evolution and natural selection.Virtually nobody "believes" in the theories of evolution and natural selection. They accept that it is the natural conclusion to be arrived at by applying reason to the evidence. As such, it is not a belief system at all.
You cannot project religious or pseudo-religious beliefs onto science. The attempts to do so betray a profound ignorance of the nature of scientific thought and knowledge.
One wonders why creationists persist in trying to claim that that acceptance of science is a belief system. Do they not profess a belief system themselves? A system of notions, based on a desire to believe, despite the evidence, despite reason? Are they trying to claim that this is a bad thing, that "evolutionism" is a bad thing because it is devoid of evidence and reason just like their own beliefs?
Of course, the truth behind this is the separation of church and state, which means that in public schools in America, it is unconstitutional to misrepresent pseudo-religious beliefs as fact. It's a "We are not allowed to do it, so they shouldn't be allowed either" argument. It fails, because, basically, evolution is an established fact.
Another common propagandist lie is, of course, the conflation of science with atheism. Most atheists accept science, just as large numbers of Christians, Muslims and Jews also accept it simply because they have no crazy reasons not to.
"Christianity"
Yet another dishonest creationist tactic is to attempt to conflate Christianity with creationism. Supposedly, "Christians" cannot accept evolution, geology, astronomy, cosmology, physics etc. This is, simply, a lie. A huge swathe of Christians and followers of the other Abrahamic religions accept the findings of all of these sciences, without abandoning their respective faiths.
The dishonesty of the "Christian" creationist position is also evident in the fact that in Islam and Judaism there are also almost identical science-denying factions. Science denial is not an exclusively "Christian" phenomenon and is not a necessary aspect of any of these faiths.
The attempt by creationists to hide behind the skirts of such venerable faith systems is not an edifying prospect. It does their cause no good whatsoever.