Evidence for Evolution


#1

Some posters here attempt to pretend that there really isn’t any evidence for evolution, that the theory merely arises from the “philosophical predisposition” of “atheist scientists”. (By “evolution” I here mean “common descent” and “descent with modification” and prescind from any particular mechanism.)

That is not to deny that such a predisposition exists. But opposition to evolution also arises from a philosophical predisposition, the desire to have the ancient beliefs of the Church and the Fathers proved correct, regardless of the evidence. I would like these posters to have the intellectual honesty to admit there simply is no evidence that could possibly convince them of evolution. Their m.o. simply consists of scanning the evidence for anything which could possibly be against evolution, while disregarding the totality of evidence. That is simply not how science is done. If their belief is that the argument to authority should always trump the argument to evidence, they should say so. I, for one, do not accept that principle. I think, however, that I have more or less “clean hands” here, meaning that I really do not adhere to the philosophical predispositions of either group.

It is admitted that complete objectivity is impossible in science. Inductive reasoning uses (or should use) Bayes’ theorem, which shows that the posterior probability of any particular model will depend on the prior probability, for which subjectivity simply cannot be avoided. Nevertheless it is possible to compare the likelihood of data under various models.

Now the piece of evidence which convinced me, once and for all, of the reality of evolution was the presence of endogenous retroviruses (ERVs) in the same location in the genome in all the major primate groups, including humans. An ERV is a virus which imbeds itself in the DNA (RNA-to-DNA is done using reverse transcriptase). Typically the virus then takes over the cell’s replication machinery until it dies. However, if something goes “wrong” in the process the DNA will enter the host DNA and stay there. Should this happen in a germline cell, and this be the gamete used for reproduction, this ERV copy will be passed on to the offspring. There are 12 or 13 of these ERVs which have been found so far (geneticists please correct if there are more) in the same location in the genome, and they follow the standard phylogeny among primates.

It can shown that this is strong evidence for common descent by comparing the likelihood of the data among the various models. If one species arose by common descent from another containing the ERV, the likelihood of the ERV being in the same place in the genome is close to one (not exactly one because a deletion event is possible). What if the species were specially created? If the second species were specially created without the ERV, then the ERV would have to become inserted in a germline cell in the exact same spot, and then this would have to become fixated in the population. The likelihood is vanishingly small. What if the second species were specially created with the ERV? We will assume then that the ERV would have some function, that the likelihood that a designer would just stick some random “junk” in the DNA with no function or a deleterious function is zero or close to zero. Now in fact some ERVs do have a useful function, for instance one ERV is associated with placental formation (syncytin). Other ERVs have a deleterious effect, being associated with cancer for instance. But, in syncytin formation, the entire ERV is not associated with syncytin. An ERV consists of three genes, env, gag, and pol, as well as a long-term repeat (LTR). But only the env gene is used for syncytin production. What’s the function of the rest of the ERV? Specifically, what’s the LTR (essentially “junk”), doing there? Why would a designer use specifically an ERV for this purpose? Why not just design an ordinary gene for syncytin?

Creationist responses in the past have typically included the following.

  1. Confusing the issue by citing ERVs not shared between primates, conveniently omitting the fact these are not in the same place in the genome, making the likelihood of independent insertions much greater.
  2. Confusing the issue by citing insertion hotspots; yes, insertion hotspots make certain regions more likely than others but insertion at the exact same location is still vanishingly unlikely in a genome with 3 billion base pairs.
  3. Confusing the issue by demanding an explanation for the differences in the genome, not just the similarities. This would be a valid point if the only options were “Biblical” creation versus atheistic, stochastic, undirected evolution. However they are not, and theories of front-loaded and/or directed evolution easily explain the similarities.
  4. Complaining that I am speculating on what a designer might or might not do. If a designer is brought into the equation, then it is necessary to do this in order to evaluate the evidence scientifically, which means evaluating likelihoods and applying Occam’s razor and parsimony. I can’t prove that angels don’t move the planets and stars around. But I can show their motion is accounted for by natural laws, which is a much more parsimonious explanation than angels, for the hypothesis space is much smaller. Why should angels be moving the planets in the exact same fashion as predicted by Kepler’s Laws, and later more accurately by general relativity? Similar considerations apply here.

Here is the AIG interpretation of retroviruses:
answersingenesis.org/articles/am/v1/n2/were-retroviruses-created-good which kind of just makes me want to say, get real.


#2

Whoa. I hadn’t read that one. “Retroviruses are good.” So HIV is a good, God-created virus…

I don’t think I can buy the idea that God designed an entity to doom little children in Africa to a lingering death.

Another reason to be leery of anything AIG is touting.


#3

I think it depends on how you define “good”. It may be that there is indeed a “good usage” to HIV, in the same way that many neurotoxins are now being found to have excellent medicinal usages.

If something went “wrong”, it wouldn’t necessarily mean that this was “God’s fault”. People could have simply abused God’s creation (via adultery and fornication for example) and unleashed it onto humanity causing a reaction that He did not intend them to use it for, but that He could nonetheless still eventually use for a “good purpose” just as He may have originally intended.

This isn’t saying that HIV is a disease sent to wipe out “adulterers” and “fornicators” either. Certainly many innocent people have suffered from HIV who had nothing to do with adultery or fornication.

Much like original sin, they may have received the suffering that resulted from other’s sins even though they themselves did nothing to deserve the suffering that they obtained due to other’s sins. In other words, they may be inheriting the suffering while not inheriting the guilt.

I also think that one of the reasons why God said not to fornicate or commit adultery (in the first place) was precisely because He knew things like HIV would eventually break out and spread further if they did not listen to Him.

PS: That was a good post SeekingCatholic. Thanks for sharing that. I see no logical reason not to accept common descent as the best reason why the retroviruses were passed along common ancestors. I think one would be hard pressed to provide an alternative “specific creation” reason why God would operate in this way too.


#4

The question of why bad things happen to people who are innocent, such as infants, is a lot more complex than “it’s really for the best.”

And trying to graft such an idea onto retroviruses is foolish, in my opinion and tends to make unbelievers resistant to accept God.

St. Augustine said it:

Often a non-Christian knows something about the earth, the heavens, and the other parts of the world, about the motions and orbits of the stars and even their sizes and distances,… and this knowledge he holds with certainty from reason and experience. It is thus offensive and disgraceful for an unbeliever to hear a Christian talk nonsense about such things, claiming that what he is saying is based in Scripture. We should do all that we can to avoid such an embarrassing situation, lest the unbeliever see only ignorance in the Christian and laugh to scorn.

I am content to accept that the question of evil is beyond man’s comprehension, and I accept God’s admonition to Job. There are things we don’t understand, and we shouldn’t make up things to explain them.


#5

No doubt. But that’s not what I’m saying.

And trying to graft such an idea onto retroviruses is foolish, in my opinion and tends to make unbelievers resistant to accept God.

Call it foolish if you want. I think the idea that there is a positive reason (a reason to hope) for anything that happens sits at the heart of the Catholic faith.

St. Augustine said it:

Often a non-Christian knows something about the earth, the heavens, and the other parts of the world, about the motions and orbits of the stars and even their sizes and distances,… and this knowledge he holds with certainty from reason and experience. It is thus offensive and disgraceful for an unbeliever to hear a Christian talk nonsense about such things, claiming that what he is saying is based in Scripture. We should do all that we can to avoid such an embarrassing situation, lest the unbeliever see only ignorance in the Christian and laugh to scorn.

I agree with Augustine on this.

I am content to accept that the question of evil is beyond man’s comprehension, and I accept God’s admonition to Job. There are things we don’t understand, and we shouldn’t make up things to explain them.

Um…death and suffering did come to man as a result of original sin…Augustine certainly believed this too…or did you not want to read that part?


#6

Barbarian observes:
And trying to graft such an idea onto retroviruses is foolish, in my opinion and tends to make unbelievers resistant to accept God.

Call it foolish if you want. I think the idea that there is a positive reason (a reason to hope) for anything that happens sits at the heart of the Catholic faith.

So, if a man loses his faith, there is a reason to hope thereby?

Barbarian observes:
St. Augustine said it:

Often a non-Christian knows something about the earth, the heavens, and the other parts of the world, about the motions and orbits of the stars and even their sizes and distances,… and this knowledge he holds with certainty from reason and experience. It is thus offensive and disgraceful for an unbeliever to hear a Christian talk nonsense about such things, claiming that what he is saying is based in Scripture. We should do all that we can to avoid such an embarrassing situation, lest the unbeliever see only ignorance in the Christian and laugh to scorn.

I agree with Augustine on this.

Enough to admit that there are things we don’t understand?

Barbarian observes:
I am content to accept that the question of evil is beyond man’s comprehension, and I accept God’s admonition to Job. There are things we don’t understand, and we shouldn’t make up things to explain them.

Um…death and suffering did come to man as a result of original sin…

That is not an explanation of evil. Man did not invent evil, nor is anything man ever did or failed to do, an explanation for it. God says that we are to accept that it is, and accept what is beyond our comprehension.

Augustine certainly believed this too…or did you not want to read that part?

I doubt if St. Augustine disagreed with God’s word in Job.


#7

The response from creationists is just deafening…


#8

I recommend everyone read Human Persons Created in the Image of God. There is much any Christian can find out on his own about astronomy just by using a good telescope (especially away from a city). It should, however, strike everyone as odd that some theory of evolution ‘needs’ to be accepted. It is not required by the Catholic Church. I do not believe in AiG or other large creationist sites. I have no idea who runs them.

God bless,
Ed


#9

I don’t really care if any particular individual accepts evolution or not. It’s a free country, and as you correctly stated, acceptance of it is not required by the Church. However for many of them it’s not likewise a mere personal decision but they are on a crusade. They really would wish that others not accept evolution, claim that there’s no evidence, and that their acceptance only arises from an *a priori *philosophical position. That gets annoying after a while.


#10

Philosophical? There is some evidence that things are not right. Polystrate (passing through several strata) fossilized trees, some extending into coal seams, exist. However, this information is not argued against in a reasonable fashion.

The same with “junk” (non-coding) DNA. It has been learned that this junk is not junk after all.

What can be annoying is the “here’s the facts and you must deal with them” statements. The Catholic Church has dealt with the facts and their interpretation fully. However, there are those that deny to the Church the ability to combine various types of reason to form a complete picture - one that includes God. Science, as it is defined today, apparently cannot and/or will not do this. I put it this way because the Catholic Church teaches that the individual can discover the existence of God through natural reason.

God bless,
Ed


#11

Philosophical? There is some evidence that things are not right. Polystrate (passing through several strata) fossilized trees, some extending into coal seams, exist.

There are some forming near my house, dead, but upright trees being slowly buried in sediment and dead vegetation in a reservoir. Been going on for decades.

The same with “junk” (non-coding) DNA. It has been learned that this junk is not junk after all.

No kidding. “Evolutionists” knew about some of it as early as the late 60s. You didn’t know that? BTW, some of it might really be junk. It’s hard to find a use for a gene that used to code for vitamin c, but now is broken.

What can be annoying is the “here’s the facts and you must deal with them” statements.

Life is like that; it’s not obligated to fit your expectations.


#12

Ed, carrying his only quixotic crusade againt Evo in CF. I think that the poster was writting to people who accept Evo in the first place. For once it will be good to do teology among those who accept Evo as a fact.


#13

Well of course it isn’t argued against. Why should it be? What’s the likelihood of polystrate fossils arising from a global flood (which I presume you are getting at) versus arising from a local sudden deposition event, such as a local flood. Well it’s about the same, so this piece of data doesn’t help much either way.

The same with “junk” (non-coding) DNA. It has been learned that this junk is not junk after all.

“Junk” could arise from random mutations in either a creationist or evolutionary scenario. But then natural selection pressures would also be present favoring the removal of such “junk” or co-option into a positive function. Again the data doesn’t favor either.

What can be annoying is the “here’s the facts and you must deal with them” statements. The Catholic Church has dealt with the facts and their interpretation fully.

That may be. I’m tired though of the shrill obscurantist types who claim “not one shred of credible evidence for evolution”, claim Pius XII “compromised” in Humani Generis, and other such nonsense.

However, there are those that deny to the Church the ability to combine various types of reason to form a complete picture - one that includes God. Science, as it is defined today, apparently cannot and/or will not do this. I put it this way because the Catholic Church teaches that the individual can discover the existence of God through natural reason.

God bless,
Ed

Finding God through science is a rather difficult task though.


#14

If the average person using natural reason can discover God, then I question science’s role. It is simply a set of observations and experiments done by men. Some people say they need to turn off their mind to believe, so do scientists turn off their minds to the presence of God as well? It would be better, I think, for science, to view reality as a whole. As Pope Benedict has stated, science, today, restricts our view and discards some aspects of reason. As I’ve written before, the Church has a Pontifical Academy of Sciences.

God bless,
Ed


#15

Re - cognizing what God has created is not hard.


#16

If. The Church only says that the existence of God is discoverable by human reason in itself, not that all humans with average or below-average intellectual attainment are capable of it. Of course this doesn’t mean science will necessarily be a help here, only that your assumption is open to question.


#17

All humans desire to know the truth.


#18

I sometimes wish that those who engage in this controversy could state clearly what their position is:

As far as I can make out there are five main positions in this discussion.

Those who are not-believers in God and accept the Theory of Evolution fully and completely along the lines of Dawkins (evolution is based on mere chance alone)

Those who are not-believers in God and accept the Theory of Eveolution with some conditions.

Those who believe in God and fully reject the Theory of Evolution.

Those who believe in God and accept an Intelligent Design adaptation of Evolution

Those who believe in God and accept the Theory of Evolution in the sense that God is the first mover and that evolution is not “mere chance.” This position is not the same as “Intelligent Design” - This is my position.

It can be so frustrating when an individual who is a follower of Dawkins discusses this issue with someone whom they think is someone who fully rejects the Theory of Evolution when they are in fact discussing evolution with a believer who does accept many concepts of evolution.


#19

To me, any debate about evolution vs creation on a Catholic board, between Catholics, is an absolute waste of time. Let me put it as plainly as I can: Catholics should not be fighting each other over this issue, because we are allowed to believe in a literal 6-day creation, or, complete “evolution” devoid of any supernatural influence, or any belief that falls within that spectrum. The only thing we are forbidden to believe is that the soul somehow “evolved”. This is fact, this is incontrovertible, and even, on this thread, a few have acknowledged this, but yet still, I see from time to time on this board, Catholics fighting among each other about this issue, as if the issue were dogmatically defined.

Meanwhile, while the extremists on both sides are busy trying to one up each other, there still remains a large field of non-Catholics waiting to be harvested, but there are no workers since the workers are busy trying to decide who’s the best worker. Nice job.

If you read anger on my part in this post you are correct; you extremists need to get your priorities straight. Quite frankly, this obsession with evolution is one of the reasons I don’t visit here much; I have no use for a board (or any fora, and there are others I infrequent for the same reason, infighting) that will have its members fight among each other when in reality, there should be NO fighting on said issue. The Church needs unity now more than ever, because there are issues that are worth fighting for, but this, is surely NOT one.


#20

You are absolutely correct. What you stated above is one of the most important reasons why I became a Catholic. We are allowed to accept the Theory of Evolution (as long as we do not believe that the soul evolved) .

The Church has allowed us to have Reason and Faith on this issue.

It is NOT an issue of faith either direction. If someone does not accept the Theory of Evolution - fine. They can love God sincerely. If someone does accept the Theory of Evolution as the Church has stipulated - fine. They can love God sincerely.


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