Evolution Between Species: Essential Questions

[Erasmus7]

Hi all,

I have posted before on the question of evolution, and here post my second query, as part of my ongoing quest to find some closure on the Creation-Evolution question. Would appreciate all comments.

The Darwinian position, as I understand it (correct me if I am wrong, science is not my field) is that a living cell, if given enough time and enough external environmental influences and pressures that prod it in the right direction (according to natural selection), would mutate and evolve in virtually any direction, within reason.

In other words, that basic cell, given enough time and opportunity, could gradually evolve into a land mammal, a fish, a bird, or perhaps more indirectly into a dinosaur or even an advanced human being. This may well at some point also require fusion with other different cells to assist with the more inventive evolutionary species development.

In other words, DNA is an incredibly inventive and complex thing and is capable of adapting or mutating in many directions. We see this in, e.g., the aggressiveness displayed by the HIV virus, which mutates so aggressively that modern science cannot keep up and find a cure. Nature seems to display similar inventiveness in many other situations as well (cf. the rapidity of life developing in a stagnant pond or carcase, etc.).

The creationist rebuttal to this would be to say that DNA is like a software programme and, while it can certainly display a certain inventiveness in micro-evolution, it is limited by its basic parametres from adapting or evolving outside of what it is ‘programmed’ to do.

Thus, e.g., if my genes say I am going to be tall with brown hair and brown eyes, I will become that. However, no amount of trying or environmental pressures will allow me to start evolving a fin (for swimming) or wings (for flying). In other words, the DNA of any given species allows for development within that species, but not for evolving sideways across to become another species as such. Thus a bird’s wings will not gradually grow scales and become fins if it finds itself having to live on or close to the sea.

NOW my question is: Is there anything currently known to science, in the construction of the gene, cell or DNA, or anything else in nature, that would stop that DNA from mutating from one species to another?

In other words, if a group of humans (in, e.g., a post-apocalyptic setting) are forced to live in a very watery environment better suited to amphibians, would that human flesh, after a long time, start to mutate and become scales? Would lungs start to change and ultimately become gills?

In other words, is there anything known to science within human DNA or genes or biology that would actually prohibit such gradual mutations from skin tissue to scales, or lung tissue to gills?

Bearing in mind, as evolutionists have pointed out, that tadpoles start off in water and with gills, and end up as amphibians (frogs) with lungs.

Perhaps another way of asking this is: what is the essential constitutional difference between: human skin, fish scales, and bird feathers? Is there anything known in cellular biology that would stop an adaptation from one to another of these?

I would really appreciate assistance with and answers to the above.

Regards,
Erasmus

 

[Hieronymus]

Why even wonder if an atheistic attempt of a model for our origins, lakcing evidence severely, is worth your while as a theist?
Why would you even believe Jesus can give you eternal life when He can't make lifeforms to start with?

Do you really find it feasible that by sloppy copying a book can change its content and thus tell a different story?
And that's just books. Living nature is ever so much more complex.

Mutations do not change the kind.

 

[Speedwell]

Sideways evolution?

Species are not pre-existing categories into which creatures evolve. Speciation is said to occur when one part of a population becomes sufficiently different from another part so that interbreeding can no longer occur.

Evolution can only occur if the trait in question exhibits variation. That is, each new generation displays random (think 'bell curve') variation of the trait from individual to individual. If the trait does not vary then it cannot evolve.
For example, if selection pressure was driving us to having wings, they would have to evolve from existing limbs, because the number of limbs we possessed stopped varying back in the Cambrian so it is too late for us to evolve an additional set.

So variation is the key to evolution. Many people labor under the false impression that creatures pretty much stay the same until every once in a while a mutation comes along which may or may not improve the creature's fitness. But what really happens is that with each new generation a range of types is presented to the environment for selection. If the environment changes there must be already in the population variants which can take advantage of the change or evolution cannot occur.

Mutation plays a role in creating that variation but is not the sole contributor.

 

[Hieronymus]

Mutation plays a role in creating that variation but is not the sole contributor.

Of course it is.
If there were no mutations, nothing different could ever be selected than that which was already there.

 

[Speedwell]

Of course it is.
If there were no mutations, nothing different could ever be selected than that which was already there.

I'm not sure I understand your comment. Without mutations, the information content of the gene pool would gradually be depleted by natural selection and consequently variation would also gradually decrease, which would bring evolution to a halt.

 

[Hieronymus]

I'm not sure I understand your comment. Without mutations, the information content of the gene pool would gradually be depleted by natural selection and consequently variation would also gradually decrease, which would bring evolution to a halt.

Exactly, evolution depends on mutations.
Only problem is, mutations can't write meaningful DNA.
It's loss of the original information / data, like in all flawed information copying.

 

[Speedwell]

Exactly, evolution depends on mutations.
Only problem is, mutations can't write meaningful DNA.
It's loss of the original information / data, like in all flawed information copying.

Unfortunately, it looks like you have been sold the bogus version of Information Theory fabricated by the Creationist ministries--along with the bogus version of the theory of evolution you love to hate.

There is no "meaningful information" encoded in DNA. All there is, is Shannon Information, which is increased by random processes.

There is more to mutation than copying error.

There is more to the variation which drives evolution than mutation.

Once again we are at the same impasse. All of your arguments are directed against a straw man.

 

[Papias]

Hi all,

Hello, and welcome! It looks like your thread got derailed a bit, so let me try to get it back on track with direct answers.

...NOW my question is: Is there anything currently known to science, in the construction of the gene, cell or DNA, or anything else in nature, that would stop that DNA from mutating from one species to another?

No, there isn't. In fact, we know speciation (one species evolving, through mutation and selection, into another) because we've seen it. We've see it for the apple maggot fly, the tunnel mosquito, and others. (we can get into those as needed). Ring species too, may be of interest to you. Google any of those as needed. A ton of other examples are here: http://www.talkorigins.org/faqs/speciation.html

The evolution of one species into another has become so clearly a fact that though evolution deniers used to widely claim that one species can't evolve into another, many evolution deniers have given up on claiming that one species can't evolve into another. Instead, some have changed their claim to say that one "kind" can't evolve into another - but they won't say what they mean by "kind", changing the term as it fits them. btw, Leviticus is clear that "kind" is at the species level or below (subspecies), so their new position isn't biblical anyway.

Hi all,

In other words, if a group of humans (in, e.g., a post-apocalyptic setting) are forced to live in a very watery environment better suited to amphibians, would that human flesh, after a long time, start to mutate and become scales? Would lungs start to change and ultimately become gills?

In other words, is there anything known to science within human DNA or genes or biology that would actually prohibit such gradual mutations from skin tissue to scales, or lung tissue to gills?

There is nothing known in human DNA or genes or biology that would prohibit that. It might take a while though, and in the meantime, some other evolutionary path of mutation/selection might evolve a different "solution". For instance, lungs didn't evolve *from* gills, but rather separately, *in addition to* gills, so some of our ancestors had both lungs and gills (like modern day lungfish do). Thus, maybe we'd evolve scales, or maybe we'd evolve some other kind of water resistant skin. It all depends on the mutations and similar factors.

Perhaps another way of asking this is: what is the essential constitutional difference between: human skin, fish scales, and bird feathers? Is there anything known in cellular biology that would stop an adaptation from one to another of these?

No, there is no "essential constitutional difference". There are certainly differences, but all of those are the results of the DNA, and the DNA can change over time to give any other type of flesh. In fact, biologists have found and mapped out many of the mutations that caused many of these changes, and found that in many cases, the same gene that produces one material (say, a feather protein) is simply a mutated form of a gene in an animal similar to the ancestor animal that makes an analogous material (say, a skin protein).

Evolution was confirmed beyond a shadow of a doubt before, but DNA reconfirmed it all over again. The ERVs are especially clear proof, that is understandable to most people. The broken vitamin C gene (GULOP) is also helpful.

(Note that youtube could have bad or good videos, in this case, both of these are supported and in agreement with the consensus of biologists - that's the key to rejecting misleading videos).

GULOP:

ERVs:

I hope all that helps-

In Christ-

Papias

 

[Resha Caner]

No, there isn't.

That's not quite right. Observing the selection of a mutation doesn't mean there are no limitations. The evolutionary model is open-ended in general, but the specifics of the ecosystem in which an organism lives limit what will happen.

What those limitations mean is very difficult to say given the evolutionary model is stochastic. I'm not aware of a mathematical scheme where the probability would go to zero. However, some simple Markov chains show the probability becomes infinitesimal so quickly that I'm unwilling to accept it is the only mechanism in play. Personally, I think emergence plays a role, but no one I know of is studying that. No doubt the evolutionary model dominates the field of biology.

 

[Speedwell]

What is your justification for the assumption that by using the word "kinds" God intended to establish an immutable divine taxonomy? It is also possible to see it as a statement of a principle right out of Darwin's ToE. The Principle of Reproductive Similarity holds that an individual offspring will only differ from its parent to a limited degree. Figs don't grow on apple trees and cows don't give birth to sheep, that kind of thing.
In fact, the naming of the creatures (which is what a taxonomy is) was specifically given to Adam, to us.

 

[mark kennedy]

Hi all,

I have posted before on the question of evolution, and here post my second query, as part of my ongoing quest to find some closure on the Creation-Evolution question. Would appreciate all comments.

The Darwinian position, as I understand it (correct me if I am wrong, science is not my field) is that a living cell, if given enough time and enough external environmental influences and pressures that prod it in the right direction (according to natural selection), would mutate and evolve in virtually any direction, within reason.

In other words, that basic cell, given enough time and opportunity, could gradually evolve into a land mammal, a fish, a bird, or perhaps more indirectly into a dinosaur or even an advanced human being. This may well at some point also require fusion with other different cells to assist with the more inventive evolutionary species development.

In other words, DNA is an incredibly inventive and complex thing and is capable of adapting or mutating in many directions. We see this in, e.g., the aggressiveness displayed by the HIV virus, which mutates so aggressively that modern science cannot keep up and find a cure. Nature seems to display similar inventiveness in many other situations as well (cf. the rapidity of life developing in a stagnant pond or carcase, etc.).

The creationist rebuttal to this would be to say that DNA is like a software programme and, while it can certainly display a certain inventiveness in micro-evolution, it is limited by its basic parametres from adapting or evolving outside of what it is ‘programmed’ to do.

Thus, e.g., if my genes say I am going to be tall with brown hair and brown eyes, I will become that. However, no amount of trying or environmental pressures will allow me to start evolving a fin (for swimming) or wings (for flying). In other words, the DNA of any given species allows for development within that species, but not for evolving sideways across to become another species as such. Thus a bird’s wings will not gradually grow scales and become fins if it finds itself having to live on or close to the sea.

NOW my question is: Is there anything currently known to science, in the construction of the gene, cell or DNA, or anything else in nature, that would stop that DNA from mutating from one species to another?

In other words, if a group of humans (in, e.g., a post-apocalyptic setting) are forced to live in a very watery environment better suited to amphibians, would that human flesh, after a long time, start to mutate and become scales? Would lungs start to change and ultimately become gills?

In other words, is there anything known to science within human DNA or genes or biology that would actually prohibit such gradual mutations from skin tissue to scales, or lung tissue to gills?

Bearing in mind, as evolutionists have pointed out, that tadpoles start off in water and with gills, and end up as amphibians (frogs) with lungs.

Perhaps another way of asking this is: what is the essential constitutional difference between: human skin, fish scales, and bird feathers? Is there anything known in cellular biology that would stop an adaptation from one to another of these?

I would really appreciate assistance with and answers to the above.

Regards,
Erasmus

In answer to your question, for limitations see my signature. Species is generally said to mean members of the population can still interbreed. There are exceptions, polar bears and grizzly, troglodyte and bonobo chimpanzees can still interbreed for example. Some primordial ancestor of all living systems on the other hand is little more then a myth.

 

[Erasmus7]

Thank you one and all. Thanks, Papias, for a good response. It appears that the issue is a lot more complex than I realized. Either way one takes the debate, one is in awe at the way God has designed creation. The imperative for life
and creation - and with that, creativity - is indeed very powerful in the infrastructure of nature and the gene.

Thank you too, Mark Kennedy - forgive my ignorance, but how do I get to your signature, as per your post above? Not terribly au fait with the computer world, I'm afraid.

 

[Erasmus7]

At this stage I would like to add another angle to the above:

On the one hand, I am struck, nay, awed, by nature’s extraordinary inventiveness and elasticity re: mutations, genes, and coming up with new and inventive adaptations on species. I.e., we have 120 000 species of fly alone. Or else, put a piece of meat out in the sun for a while or examine a stagnant pool to see the sort of inventiveness nature displays in the multiplication of life that results.

Likewise, the malaria virus is so aggressive in its mutative inventiveness that our science can only just keep up with it to find a cure. HIV mutates at a rate 7 times more aggressive than malaria, thus science cannot (yet) find a cure for it.

Where I am ‘stumped’, however, is that, yes, nature seems over-eager to produce variations within a species direction – Darwin’s finches being one example. Thus there are millions of examples of highly inventive adaptations within given species. However, there appears not to be very much at all in terms of nature's desire to be just as inventive in crossing the boundary unto another species. It seems to shy away from this (unless I am wrong; if not, please correct me).

Nature seems not to want to cross boundaries. One of the key theological themes of Genesis is ‘separation’ (I do not have space to go into it here). In Genesis 1 the word ‘separation’ occurs several times. Elements in creation keeping separate from other elements is a key part of the Genesis creation setup. It is when boundaries are crossed that chaos creeps into God’s creation (again, a Major theme in Genesis that I can’t go into here).

As far as nature is concerned: we do not see generally cats breeding with dogs, sharks breeding with whales, eagles breeding with vultures, etc. The liger only came about after a long arduous attempt by humans to mix lion and tiger. As it is, the male is sterile (although the female isn’t) – perhaps this is why nature does not like to go down these paths, because they are counter-productive to the nature life imperative. Thus too in human terms, if father mates with daughter, there is a negative nature response – i.e., often a retardation. Thus nature does not seem to like crossing boundaries for good reasons: it is not best for the species in question, and produces problems.

Now I wonder if the scientist might explain this as follows: Nature would only cross to a whole new species if environmental pressures became so great that this was the only path (or the best path) left open to it.

I noted that many of the great shifts in biological species occurred following the five or so major ‘Extinction Events’ in primeval history: a major environmental threat or catastrophe takes place, and as a result nature tends in a new direction. Thus the Cambrian Explosion produced an explosion of wholly new and varied life forms, another Event produced the dinosaurs, another killed off the dinosaurs and reared the mammals, etc.

One part of me might be inclined to see these new ‘ages’ between ‘Extinction Events’ as new acts of divine creation, perhaps corresponding with the Days of Genesis.

However, the Darwinist might perhaps say that the mighty pressures produced by these ‘Events’ forced the ‘nature imperative’ to do something radically different: evolve to produce dinosaurs, to produce mammals, whatever. Might I be right, then, in saying that the Darwinist would say that evolution is only as radical as it needs to be – i.e., nature would only do something as radical as change to a new species if the environmental pressures forced it to do so?

In other words, this would be a way of explaining why there is so little evidence in nature of evolving to create a whole new and different species.

On the other hand, of course, the fact that there is so little evidence to do so would be taken by creationists as evidence that nature neither desires nor chooses to go in such drastic directions, i.e., that it shies away from 'boundary crossing', as the theological import of Genesis seems to teach.

Again, I am not a scientist, and am only speculating, but would appreciate your commenting on the above.

Regards,
Erasmus7

 

[mark kennedy]

Thank you one and all. Thanks, Papias, for a good response. It appears that the issue is a lot more complex than I realized. Either way one takes the debate, one is in awe at the way God has designed creation. The imperative for life
and creation - and with that, creativity - is indeed very powerful in the infrastructure of nature and the gene.

Thank you too, Mark Kennedy - forgive my ignorance, but how do I get to your signature, as per your post above? Not terribly au fait with the computer world, I'm afraid.

The signature is the quote at the bottom of my posts. Welcome to the boards, let me know if you need help with anything.

 

[sfs]

Exactly, evolution depends on mutations.
Only problem is, mutations can't write meaningful DNA.
It's loss of the original information / data, like in all flawed information copying.

What do you think stops mutations from writing meaningful DNA? Mutations can change any sequence of DNA into any other.

 

[sfs]

In other words, that basic cell, given enough time and opportunity, could gradually evolve into a land mammal, a fish, a bird, or perhaps more indirectly into a dinosaur or even an advanced human being. This may well at some point also require fusion with other different cells to assist with the more inventive evolutionary species development.

Yes, this is pretty much an accurate statement of scientific understanding.

NOW my question is: Is there anything currently known to science, in the construction of the gene, cell or DNA, or anything else in nature, that would stop that DNA from mutating from one species to another?

No, there is nothing known to science that would stop DNA from mutating in ways that changed one species into a new species.

In other words, if a group of humans (in, e.g., a post-apocalyptic setting) are forced to live in a very watery environment better suited to amphibians, would that human flesh, after a long time, start to mutate and become scales? Would lungs start to change and ultimately become gills?

In other words, is there anything known to science within human DNA or genes or biology that would actually prohibit such gradual mutations from skin tissue to scales, or lung tissue to gills?

That's actually a somewhat different question. What evolutionary biology tells us is that nothing would prohibit humans from evolving all sorts of adaptations to (say) an aquatic environment. If there were some advantage to having scales (although it's not obvious to me why that would be advantageous), they could evolve something like scales, but they probably wouldn't be exactly the same as any of the various kinds of fish scales; they would be a development from something that humans already have. They would be very unlikely to evolve gills, but would evolve ways of optimizing air breathing while living in the water. Land animals have returned to aquatic environments many times (plesiosaurs, mosasaurs, ichthyosaurs, thalattosaurs, thalattosuchians, sea snakes, whales, sea turtles), and have never re-developed gills. Evolution can go forward in many directions, but cannot (except in the simplest cases) go backwards.

More generally, complex organisms are constrained in how they can evolve by their developmental processes, which are too involved and interdependent to change core features easily. A single cell can evolve into starfish (which have fivefold symmetry) or into skunks (which have bilateral symmetry), but skunks aren't going to evolve into starfish: they have too many developmental processes built on the bilateral framework.

ETA: But humans may be able to evolve back into single-celled organisms -- look up HeLa cells.

 

[sfs]

Likewise, the malaria virus is so aggressive in its mutative inventiveness that our science can only just keep up with it to find a cure. HIV mutates at a rate 7 times more aggressive than malaria, thus science cannot (yet) find a cure for it.

Pedantic note (because I study both malaria and viruses): malaria is not caused by a virus. It's caused by a intracellular parasite. And even though malaria mutates much slower than HIV, it still quickly evolves resistance to drugs.

Where I am ‘stumped’, however, is that, yes, nature seems over-eager to produce variations within a species direction – Darwin’s finches being one example. Thus there are millions of examples of highly inventive adaptations within given species. However, there appears not to be very much at all in terms of nature's desire to be just as inventive in crossing the boundary unto another species. It seems to shy away from this (unless I am wrong; if not, please correct me).

Darwin's finches aren't a single species; they're an example of how single species can give rise to the kind of varied specis you're talking about. Here's an even better example:
http://www.hdouglaspratt.com/Art_Gallery/Other/representativehoneycreepers2010.html
These are Hawaiian honeycreepers. They're all descended from a single species of finch that landed on the Hawaiian islands a few million years ago. They are quite diverse, and are clearly different species.

Nature seems not to want to cross boundaries. One of the key theological themes of Genesis is ‘separation’ (I do not have space to go into it here). In Genesis 1 the word ‘separation’ occurs several times. Elements in creation keeping separate from other elements is a key part of the Genesis creation setup. It is when boundaries are crossed that chaos creeps into God’s creation (again, a Major theme in Genesis that I can’t go into here).

Quite true. The theme of a god taming chaos is a common one in the ancient Near East. The authors of Genesis picked up that theme and (with modifications) used it in describing God's creation of the world.

As far as nature is concerned: we do not see generally cats breeding with dogs, sharks breeding with whales, eagles breeding with vultures, etc. The liger only came about after a long arduous attempt by humans to mix lion and tiger. As it is, the male is sterile (although the female isn’t) – perhaps this is why nature does not like to go down these paths, because they are counter-productive to the nature life imperative.

There is certainly a selective advantage in not trying to mate with incompatible species, so yeah, nature tends to avoid that route (especially if what you're trying to mate with considers you supper). On the other hand, bacteria exchange DNA with very different bacteria pretty freely, and plants frequently cross species barriers to hybridize. It's a major source of new plant species.

Thus too in human terms, if father mates with daughter, there is a negative nature response – i.e., often a retardation. Thus nature does not seem to like crossing boundaries for good reasons: it is not best for the species in question, and produces problems.

It's not clear how this example connects with crossing boundaries. The problem with incest is that the two are too close genetically, not that they're across some kind of barrier.

Now I wonder if the scientist might explain this as follows: Nature would only cross to a whole new species if environmental pressures became so great that this was the only path (or the best path) left open to it.

I noted that many of the great shifts in biological species occurred following the five or so major ‘Extinction Events’ in primeval history: a major environmental threat or catastrophe takes place, and as a result nature tends in a new direction. Thus the Cambrian Explosion produced an explosion of wholly new and varied life forms, another Event produced the dinosaurs, another killed off the dinosaurs and reared the mammals, etc.

One part of me might be inclined to see these new ‘ages’ between ‘Extinction Events’ as new acts of divine creation, perhaps corresponding with the Days of Genesis.

However, the Darwinist might perhaps say that the mighty pressures produced by these ‘Events’ forced the ‘nature imperative’ to do something radically different: evolve to produce dinosaurs, to produce mammals, whatever. Might I be right, then, in saying that the Darwinist would say that evolution is only as radical as it needs to be – i.e., nature would only do something as radical as change to a new species if the environmental pressures forced it to do so?

We wouldn't use the language you are here. Rather, we would say that species tend to evolve in whatever direction is available to them. If there are multiple directions available, the species will probably split and become two or more species. Mammals were around long before the dinosaurs became extinct, but it was only after the extinction event that lots of ecological niches became available for mammals to fill, and so they diversified dramatically. This is known as an adaptive radiation. The honeycreeper example from before is a smaller example of the same phenomenon; they split into such highly diverse species because there were no other land birds on the islands at the time.

In other words, this would be a way of explaining why there is so little evidence in nature of evolving to create a whole new and different species.

There is an enormous amount of evidence that new and different species have evolved millions of times.

 

[juvenissun]

Here's an even better example:
http://www.hdouglaspratt.com/Art_Gallery/Other/representativehoneycreepers2010.html
These are Hawaiian honeycreepers. They're all descended from a single species of finch that landed on the Hawaiian islands a few million years ago. They are quite diverse, and are clearly different species.

WHY would small islands like the Hawaiians be capable to allow the evolution of so many species? Would two or three be a more reasonable number of evolved species? What are the forces behind the evolution?

 

[Speedwell]

WHY would small islands like the Hawaiians be capable to allow the evolution of so many species? Would two or three be a more reasonable number of evolved species? What are the forces behind the evolution?

Lack of outside competition. Those creatures who were able to reach the island had more empty ecological niches open to them.

 

[juvenissun]

Lack of outside competition. Those creatures who were able to reach the island had more empty ecological niches open to them.

That sounds like a negative factor to promote evolution.