Where's the evidence *against* evolution?

Great Debates
21

If evolution didn’t occur, there are a couple of things we would expect to see:

In the absence of a Divine Entity:

  1. All life forms should be simple, protoplasmic gobs of goo, at best. There would be no impetus for change, or even a means to do so. In short, ‘Life’ would consist of little more than a few complex molecules.

or,

In the Presence of a Divine Entity:
2) All life forms would be perfectly suited to their environments. All life forms would be, from an engineering standpoint, perfectly designed.

Of course, we see neither of these. Organisms do change. And, from an engineering standpoint, most organisms appear to be cobbled together from available parts (that is, an organism’s structure is dependent on its ancestor’s).

From APB9999:

The problem with this, as I see it, is that mutation rate is not necessarily a constant. In times of high environmental stress, the mutation rate may increase, thereby also increasing the total number of ‘beneficial’ mutations. This would be consistent with the concept of punctuated equilibrium.

Also, some things to keep in mind: evolution, unless one is completely oblivious to facts, is pretty much a given. Organisms change, and I can’t see how any thinking being can argue otherwise. The questions regard the mechanism. This is, of course, where Darwin, et al., came in. Darwin proposed a viable mechanism, namely natural selection, to explain what was observed. Discrepancies between mutation rates and the fossil record can only call into question the mechanism of evolution, not the fact that it happens.

22

keep in mind that mutation is not the only process at work in evolution to increase diversity (e.g., there’s also recombination, gene flow, etc.)
To the OP…one problem creationists have is that scientifically speaking, it is a “fact” that evolution occurs, and it is only the “how/why” aspects of it that is a “theory” up for debate (of course, creationists just deny that it is a fact)

23

That’s why saltationism is improbable.
I think that genetic defects can be classified as macromutations, which are typically harmful. But micromutations are more subtle, things like having an additional layer of photocells in your retina, or the last three bones in your jaw moving to a point where they pick up more vibrations in the air. I think that sufficiently small mutations are as likely to help reproductive success as they are to hurt it.

PaulYeah

24

To be a bit of a devil’s advocate for a moment. (I personally believe in the the creation story as a non-literal explaination of the beginning, but taking the view from a literalist for the moment.) Evolutionists are always saying that no one can scientifically disprove evolution so it must be right. Thats kind of like the 49’ers forcing the Yankee’s to play a game of football, beating the crap out of them and saying they are the better team.
Creationism isn’t supposed to be able to be proven scientifically, thats why it’s called having faith. If something was the obvious, intuitional way it wouldn’t need faith, it would be logic. Evolutionists(scientists) defined they rules of the game to be the way they want, then claim they win, but they are two entirely incompatable systems of thought, and you can’t debate between them.

Plus the fact any scientist who is personally offended by the thought that creationism could be right, isn’t a very good scientist. Throughout history science has changed its approch radically, from the greek thought that if it was logical it was true, and didn’t need to be tested.
Up until the early 20’th century the main driving principal of science was that everything reacted occording to laws, and with sophisticated enough equipment it was describeable. Then suddenly quantum theories came along and blew that very priciple of science up, hell even Einstein couldn’t bring himself to believe most of Quantum logic and he proposed most of it.
(Hmmmmm…My point in that last paragraph got kind of lost, and I can’t remember what it was, but you can rest assured whereever it was going, it was brilliant :slight_smile: I left it in incase I remember enough to explain it later.

25

Consensus seems to be that it is not possible to estimate the amount of changes needed. Is this the consensus of the scientific community, or merely of the SD posters?

PaulYeah,

Is it testable?

26

Evolutionists claim that evolution cannot be proven scientifically wrong because it is an observable fact, not a theory. The sun shines, stars move across the sky, organisms change. These are observable facts. They are not ‘theories.’ (OK, so that was redundant…) The theories come into play when attempting to describe a mechanism for these observations. Evolution cannot be disproven; the mechanisms behind evolution can be. And that is a subtle distinction that is often lost on creationists.

27

According to a study by the National Institute of Allergy and Infectious Diseases (NIAID), “The gene mutation that causes cystic fibrosis also appears to protect against infection with typhoid fever.”

So what may look like a genetic defect, which causes a highly fatal childhood disease, may actually be a genetic enhancement which protects carriers from being wiped out by typhoid.

Similar connections have been found between other disease causing mutations and protection against disease (sickle cell anemia carriers, for instance, have greater protection against malaria).

Of course, a dominant mutation which wipes out all carriers before they can reproduce disappears almost immediately. But it’s not as simple as saying “this mutation - good. That mutation - bad.”

Report on NIAID Study:

http://www.eurekalert.org/releases/nih-cyfib.html

28

This is turning into an argument about ontology (if I understand the meaning of that word correctly). If faith had ever been shown to be useful for determining the way the universe works in a testable way, I’d consider it. However, since it leads to so many mutually contradictory conclusions, I can’t consider it useful. Therefore, let’s keep the thread on track, please. We’re talking about evolution here, not religion.

PaulYeah

29

Izzy, I’m not sure about that. I’d love to hear from a geneticist or another expert on the matter.

PaulYeah

30

Izzy, we’re trying to count the number of changes it takes to get from literal pond scum to, say, Jennifer Lopez. Most changes would be too small, or too long ago, to show up in the fossil record. I suppose we could count all of the changes that we definitely know about, but it sounds like a bitch of a job. Count 'em yourself.

31

Here are a random smattering of links which may (or may not) be helpful:

A creationist’s view:
http://www.thewilliamsweb.com/fairytale/articles_debates/mutation_rate.htm
http://www.cs.unc.edu/~plaisted/ce/problem.html
http://www.niaid.nih.gov/dait/cross-species/page5.htm

This site has a very unfortunate background, making it nearly impossible to read:
http://www.marlboro.edu/~lmoss/planhome/thesis/litrev/08.2.mute.rate.html

http://www.abcnews.go.com/sections/science/DailyNews/mutation990127.html

32

To IzzyR

A. Individuals with beneficial mutations:

  1. Albert Einstein.
  2. Michael Jordan.
  3. Marilyn Monroe.

Are you taller than either of your parents? If so, than you too can be a mutant!

B. Izzy, I don’t think you grasp the scale here. Life has been evolving on thi planet fo a billion years now, and that’s a very long time. Add to that the total biomass of this planet (pretty damn large) and the fact that the important factor in evolution is hoe often the creature reproduces - most animals bear young within a year, so every million years you have a million generations, a million chances for a change to take place. And a million years is peanuts when it comes to evolution. It’s a lot like the old “thousand monkeys typing for a thousand years” thing; eventually, they typed up mankind.

(Of course - as one religeous guy to another - there’s no reason to assume that those monkeys didn’t have a bit of divine inspiration. My argument with the creationists is one of method, not meaning.)

33

Wow. I continue to be amazed at how consistently evolution-deniers are able to completely ignore natural selection, the very centerpiece of Darwinism. But I suppose the strawman argument all they’ve got.

PaulYeah

34

Wolfman, I’ll add a bit to the answers from Mauve Dog and PaulYeah (sorry, this’ll be my last ontological aside, Paul):

I don’t think that’s true. Evolution fits the facts–that’s what science is all about. Models change, theories are altered or abandoned, assumptions are disproven based on gathered evidence. Until and unless evolution is disproven (which would require explaining away the mountains of evidence in its favor), it’s the only game in town.

Science does not deal in Truth. It deals in observable fact. Truth is for philosphers.

Well, yes, that’s exactly right. Science does not deny faith. Science says little about faith, because, as you say, they’re two different beasts. The problem arises when Creationists try to tackle evolution on the scientific playing field. Either you accept the evidence or you don’t, but if the latter, you’d better not make the mistake of saying evolution is wrong on scientific grounds without having some scientific evidence to back it up.

It’s fine to say “I refuse this evidence on faith,” as long as you realize that it is faith and in contravention to observation.

35

PaulYeah;
I don’t understand your use of the terms "Micromutation’ and “Macromutation”. Isn’t macro a change in a large scale structure like the retina or jaw, while micro is a change on the molecular level? At any rate, all mutations involve a change on the molecular level because you don’t get inheritable alterations in retinas or jawbones unless those changes are encoded in the genes at the DNA level.

Tenesee Ben:
If Dawkins claims that micro mutations are 50/50 likely to be better, he has a lot of hard arguing to do. There is no smaller (nonsilent) mutation than the substitution of one nucleotide for another, causing substitution of one amino acid for another. Because natural selection has already created the genes we are carrying, and mutations occur randomly, any such mutation has a far smaller than 50% chance of being advantageous, on the face of it. It is much more likely to be harmful (or silent). If you doubt this, I can give a long list of single mutations that are lethal; how many mutations can you or Dawkins give that enhance human ability? There are a handful, but even those, like sickle cell, are usually accompanied by severe problems at least in the homozygote.

Mauve Dog:
Your point about rates of mutation is well stated, and a serious problem. I believe there are estimates of average rates over long periods, though, for many organisms. Still, the best we could get is a ballpark figure.
I don’t expect the rates to be off, anyway; I accept evolution, as does everyone who has ever taken the subject seriously from a scientific point of view. But the OP was asking what evidence we might see if evolution DIDN’T occur. If there were demonstrable discrepancies between the rates at which change can take place through descent, and the rate at which we observe the fossil record presenting us with new forms, it would indeed require a serious rethinking of the theory of evolution, as I currently understand it anyway.

Alessan:
You’ve given examples of people whose accomplishments are great (well I don’t know about Miss Monroe), but it’s not clear that they are related to genetic mutations. The range of abilities in the normal (by which I mean non-mutant) population is large, and Michael Jordan, for example, need not be a mutant to be a great basketball player.

36

On the subject of the number of mutations required to get from there to here:

The two most significant factors in estimating that number are probably the rate of reproduction and the genetic diversity of the offspring that survive. The rate is significant because it allows for more mutations to express themselves over a shorter period of time. The diversity is important because (to use an analogy from programming) it represents the degree of parallel computation that the system can support, and the higher the degree of parallelism, the greater the number of possible “successful” mutations.

Now, both of these factors are extremely hard to gauge with any accuracy. As far as reproductive speed goes, we could for example use modern bacteria as an analogue for the original bacteria, and assume the rates are similar, but we’re still guessing. As complexity increases, the rate of reproduction decreases, but it’s hard to come up with an accurate estimate of how the rate slowed over time, because we don’t know exactly when, in what exact order, and over what period of time, the thresholds of complexity that slowed reproduction were added.

As for the amount of genetic diversity in a given population, the fossil record gives us evidence of a time when an organism existed, but we don’t know for sure when the first of such an organism existed, nor can we be sure of how many there were. There’s lots of estimating going on here! (Analysing DNA is starting to provide good clues here, though).

On the subject of what makes a mutation “advantageous” and what makes it “disadvantageous”:

Barring mutations that are fatal to the organism, the fact of the matter is that for most mutations, the value of the mutation is a highly subjective matter.

As an illustration, take the case of the genetic mutation that gives rise to immunity from HIV. (Details here.) This mutation was considered a relatively benign “flaw” in the immunological system. Very possibly conditions might have arisen which exploited this “flaw” to the detriment of those who had it. As it happens, conditions arose which favored those who had the mutation. So whether the mutation is favorable of not depends on local conditions. In fact it is still possible that at some point in time other conditions may arise which are unfavorable to those with the mutation.

Point being, again, that for the most part a mutation is just a mutation and whether or not it’s useful can change at any point in time and from many perspectives.

This makes it all the harder to come up with some kind of number estimating what percentage of mutations are favorable.

37

OK, how about this mutation:

There are a group of people in Italy, all descended from the same person, who do not get hardening of the arteries. They can eat all the fatty foods they want, and not get that form of heart disease. Which is a good thing for an Italian! 8^)

Does this count as a beneficial mutation?

38

actually, i think ms. monroe was the only one who belonged in the list. she was polydactyl.

but that brings up another point. so much of what people have been referring to in this thread about ‘genetic mutations’ is actually an inherited trait caused by a mutation many generations ago.

39

But there are those with mutations that make them better suited for their environment. For example, those who live in the Arctic regions are short-limbed, barrel-chested, and have broad noses. Those mutations are beneficial to a group who absolutely must preserve every calorie of heat they generate, and who must keep the extremities warm to prevent frost damage. The way that is done is by making the circulatory system as compact as possible, giving the blood as little chance as possible to throw heat away into the outside air. Those who live on the savannas are long-limbed, narrow-bodied people. Those mutations help them do the opposite of what the Inuit hope to achieve: They want to give up as much heat as possible because the African grassy plains are hot. Giving up heat is done the opposite way as retaining heat is done, favoring large, far-flung circulatory systems to give the blood as much chance as possible to radiate heat into the air. Those are rather simple examples, but they prove a point: Humans, with all their travelling, have produced variations on the base phenotype as they adapted to their milleiu. However, all of these variations are cross-fertile (ask the Spanish), keeping Homo sapiens sapiens (modern man, as opposed to the archaic tool users) a single species.

40

This is from the ABCNews link that I posted earlier:

Judging from this, it does not seem that mutation rates have really been examined in any depth, aside from organisms with rapid life cycles (bacteria, virii, etc.). And I don’t think you can extrapolate mutation rates for a virus to mutation rates in a population of three-toed sloths.

As for the ‘unexpectedly high’ mutation rates in humans, I would think (though I haven’t actually sat down and thought about it sufficiently to be certain) that the advent of society, and, certainly, medicine, has altered the mutation rate significantly.

As to the first part, I posted earlier on what I think we might expect to see if evolution did not occur. As for the rates at which change can occur, I would certainly not expect that actual rates of mutation would match theoritical maxima. So I’m not really certain that this is a viable path to tread down.
Besides, rates of genetic mutation may be (I would guess that they are) significantly higher than rates of morphological change. So I don’t think one can extrapolate from a rate in genetic mutation to speciation rates (which we can get a fair idea of via the fossil record). Remember, it takes a lot more than a few genetic changes to create a new species.

The moral of this story, I guess, is that there would be so much fudging and guesswork involved in the ‘mutation rate vs. the fossil record’ test that virtually any result could be obtained.