How far back...

[SoulReason]

...can we trace our genetic roots?
Common descent is supposed to be pretty bullet proof, so hop to it guys and gals.
SR

 

[philadiddle]

...can we trace our genetic roots?
Common descent is supposed to be pretty bullet proof, so hop to it guys and gals.
SR

Our phylogenetic tree includes all life. If we look at a sequence of genetic code that all of life contains, then we can examine the differences in the mutations to see if it fits our family tree that we've also constructed from morphology and bio geography. It turns out that it works with all different sorts of genetic data, from cytochrome C, to chromosomes, to ratios of junk DNA, to retrovirus insertions, etc etc. Our genetic heritage goes back far enough to include all life that is currently on earth.

 

[gluadys]

...can we trace our genetic roots?
Common descent is supposed to be pretty bullet proof, so hop to it guys and gals.
SR

A fascinating little study in tracing our genes is Deep Ancestry by Spencer Wells. He explains the techniques of tracing genetic ancestry back as far as Mitochondrial Eve (about 60,000 years ago) i.e. to the last maternal common ancestor of today's generation of humanity.

Of course, she wasn't the beginning of humanity. There are H. sapiens fossils much older. As philadiddle said, our genetic roots encompass all of life.

 

[SixStringPlank]

...can we trace our genetic roots?
Common descent is supposed to be pretty bullet proof, so hop to it guys and gals.
SR

What the other posters have said. You might want to do a search for the Tree Of Life project. They are amassing a pretty good collection of links that show the relationship and diversity of life on Earth.

 

[SoulReason]

Our phylogenetic tree includes all life. If we look at a sequence of genetic code that all of life contains, then we can examine the differences in the mutations to see if it fits our family tree that we've also constructed from morphology and bio geography. It turns out that it works with all different sorts of genetic data, from cytochrome C, to chromosomes, to ratios of junk DNA, to retrovirus insertions, etc etc. Our genetic heritage goes back far enough to include all life that is currently on earth.

Ah, refreshing - a decent reply. It is difficult to get a reply such as this on some sites.
I am attempting to come to terms with the idea of common ancestry and have a few humps to hurdle in my thinking. And not being a qualified person, the reems of information out there is too much to wade through with limited time constraints, so I ask these questions in these forums hoping to "cheat" by cutting the corners to the good stuff.
I will present some of my "humps".
Firstly, does such genetic proof for descent by modification necessarily eliminate the need for God, or is it only possible (since DNA is so cleverly impressive by its design AND function) because of Him, and His intelligent design?
Next, I see a leap of faith to assume that those genomes we can't examine, by default get "inserted" where we think they should go and it (the Phylogenetic tree) is then considered a true representation of the tree of life, and presented as such to the general public?
Btw, I will investigate your ideas, have some reps.
SR.

 

[SoulReason]

A fascinating little study in tracing our genes is Deep Ancestry by Spencer Wells. He explains the techniques of tracing genetic ancestry back as far as Mitochondrial Eve (about 60,000 years ago) i.e. to the last maternal common ancestor of today's generation of humanity.

Of course, she wasn't the beginning of humanity. There are H. sapiens fossils much older. As philadiddle said, our genetic roots encompass all of life.

Thanks for the suggestion, I will look into it.
SR.

 

[gluadys]

Ah, refreshing - a decent reply. It is difficult to get a reply such as this on some sites.
I am attempting to come to terms with the idea of common ancestry and have a few humps to hurdle in my thinking. And not being a qualified person, the reems of information out there is too much to wade through with limited time constraints, so I ask these questions in these forums hoping to "cheat" by cutting the corners to the good stuff.
I will present some of my "humps".
Firstly, does such genetic proof for descent by modification necessarily eliminate the need for God, or is it only possible (since DNA is so cleverly impressive by its design AND function) because of Him, and His intelligent design?
Next, I see a leap of faith to assume that those genomes we can't examine, by default get "inserted" where we think they should go and it (the Phylogenetic tree) is then considered a true representation of the tree of life, and presented as such to the general public?
Btw, I will investigate your ideas, have some reps.
SR.

Starting with the last question.

No phylogenetic tree is "a true representation" of the tree of life. It is a model and it is an imperfect model, but we hope that as scientists keep studying various species and species groups that the model is becoming more accurate. There is a high degree of confidence around some of the major branches but the placement of a lot of the smaller branches and twigs are very controversial and with over a million catalogued species (and perhaps ten times that many not catalogued yet) there are many sections of the tree that haven't been properly studied at all. But this isn't as much as a problem as it might appear. One could have a lot of controversy over the exact placement of each of the hundreds of fruit fly twigs on the fruit fly branch, but there is no controversy that they are all fruit flies. No one would suggest that perhaps we should place them somewhere among the Lepidoptera instead.

If you check out the Tree of Life Project Tree of Life Web Project most pages have a section on phylogenetic relationships and discuss what studies have been done. Some of it is very technical and it takes some time for a layperson to figure out the vocabulary, but it gives a good idea of the current status of many branches down to the species level.

Now back to the earlier question.

It depends on what you mean by "the need for God". When Newton did his early work on gravity he was not quite able to get the theoretical planetary orbits to match the observed planetary orbits. When he could not find any way to account for the discrepancy, he eventually suggested that God nudged the planets now and again back into their observed orbits. This is "needing God" in the sense that some direct, divine action is necessary to keep planets orbiting as they do. A century later, Laplace figured out where Newton's theory was wrong. He was able to do new calculations that matched observed planetary motion. When asked about the role of God he answered "I had no need of that hypothesis."

If "the need for God" means that God has to be part of the hypothesis, there is no place for God in any scientific theory. God is not part of an equation, nor a force that can be measured and probed by human minds and methods. And that is as it should be.

On the other hand, if by "the need for God" you mean that God is the creator of the natural world, and the one who sustains all its laws and processes, so that "it is only possible because of him" nothing in science eliminates the need for God---neither at the initial creation of the universe, nor at any moment since.

 

[philadiddle]

Ah, refreshing - a decent reply. It is difficult to get a reply such as this on some sites.
I am attempting to come to terms with the idea of common ancestry and have a few humps to hurdle in my thinking. And not being a qualified person, the reems of information out there is too much to wade through with limited time constraints, so I ask these questions in these forums hoping to "cheat" by cutting the corners to the good stuff.
I will present some of my "humps".

If you look back far enough on this forum you will see me as a strong YEC. I remember seeing the evidence for an old earth building up, but I still couldn't get my head around evolution. It took me a while till I finally swallowed my pride and accepted it, even after arguing hardcore for the YEC position. I think I've truly seen the glory of God by appreciating science for what it is, instead of trying to explain it away.

(Note: The underlined words are links to information, they are not underlined for emphasis.)

Anyways, if you want some shortcuts you should try the C&E thread archives. That forum is inactive now but some of the discussions were quite in depth. The first two posts in that thread are an index of discussions that had a lot of substance to them. The third post is the infamous "Quiet Threads". Those are the threads that never seemed to get a response from the opposition. The problem with the third post is that it links to a single post, and some of the articles are 2 posts long. So it is best to go directly to the quiet thread found here.

Firstly, does such genetic proof for descent by modification necessarily eliminate the need for God, or is it only possible (since DNA is so cleverly impressive by its design AND function) because of Him, and His intelligent design?

When we pray for rain and it rains, does our knowledge of meteorology eliminate the need for God, or does God work through the natural mechanisms that He put in place? I think part of the problem that some Christians have is that they feel the need for God to be a causal agent in the same way relativity causes things to happen. But there are different causes that exist in philosophy. If you have a read on Aristotle's four main causes, you will find that God fits nicely into the final cause, or telos. This is because God is really a claim of teleology. And that is exactly what the creation account is, an account of teleological truths.

We look at the most beautiful landscapes and see God's handiwork, yet fail to recognize the random processes used to create that landscape. God knew what He was doing when He set up the laws of the universe. I must ask you, don't you ever feel that inserting God as an explanation somehow downplays all of the things He does via natural causes? Most people answer this by saying "No, what God does through nature is just as amazing as what He does supernaturally!" Then I would have to say, why all the fuss about God not being supernaturally involved in evolution? Doesn't it speak of His glory in the same way as everything else that we observe to have natural causes? My last point, is that some philosophers, such as Alvin Plantinga also argue that evolution is a better fit for the theistic worldview, and not the atheist's worldview. Here is an article on that line of reasoning.

Next, I see a leap of faith to assume that those genomes we can't examine, by default get "inserted" where we think they should go and it (the Phylogenetic tree) is then considered a true representation of the tree of life, and presented as such to the general public?
Btw, I will investigate your ideas, have some reps.
SR.

What can't we examine? I think I'm misunderstanding this question.

 

[SoulReason]

If you look back far enough on this forum you will see me as a strong YEC. I remember seeing the evidence for an old earth building up, but I still couldn't get my head around evolution. It took me a while till I finally swallowed my pride and accepted it, even after arguing hardcore for the YEC position. I think I've truly seen the glory of God by appreciating science for what it is, instead of trying to explain it away.

You and I are very similar in that I was (until late last year) a strong Yec.
I then went to Oec as a result of finally reconciling science with the Genesis account. I still have many questions appearing as I continue to learn. And I too can see a clever plan of how it all works together.

(Note: The underlined words are links to information, they are not underlined for emphasis.)

Anyways, if you want some shortcuts you should try the C&E thread archives. That forum is inactive now but some of the discussions were quite in depth. The first two posts in that thread are an index of discussions that had a lot of substance to them. The third post is the infamous "Quiet Threads". Those are the threads that never seemed to get a response from the opposition. The problem with the third post is that it links to a single post, and some of the articles are 2 posts long. So it is best to go directly to the quiet thread found here.

I will check them out as time allows. I don't post a lot in here so my searches for my own posts are easy.

When we pray for rain and it rains, does our knowledge of meteorology eliminate the need for God, or does God work through the natural mechanisms that He put in place? I think part of the problem that some Christians have is that they feel the need for God to be a causal agent in the same way relativity causes things to happen. But there are different causes that exist in philosophy. If you have a read on Aristotle's four main causes, you will find that God fits nicely into the final cause, or telos. This is because God is really a claim of teleology. And that is exactly what the creation account is, an account of teleological truths.

Obviously God works through the things He put in place, but I thought that as a Yec also.

We look at the most beautiful landscapes and see God's handiwork, yet fail to recognize the random processes used to create that landscape. God knew what He was doing when He set up the laws of the universe. I must ask you, don't you ever feel that inserting God as an explanation somehow downplays all of the things He does via natural causes? Most people answer this by saying "No, what God does through nature is just as amazing as what He does supernaturally!" Then I would have to say, why all the fuss about God not being supernaturally involved in evolution? Doesn't it speak of His glory in the same way as everything else that we observe to have natural causes? My last point, is that some philosophers, such as Alvin Plantinga also argue that evolution is a better fit for the theistic worldview, and not the atheist's worldview. Here is an article on that line of reasoning.

I was never surprised at what I imagined God was capable of, and that is just with a finite mind.
I still am not convinced about a single common ancestor, and have yet to see any convincing data to point at one.
It would not surprise me if God did actually intervene somehow in placing the various major groups as explained to us in the Genesis account. After all, it seems pretty amazing (even beyond the realms of credibility) for whole kingdoms to evolve from natural selection/mutations, especially in light of the fact that we have yet to find evidence of jumps across "barriers" higher than a genus level. Iow, I see the likelihood of at least three ancestors and possibly as many as eight, not just a single one.

What can't we examine? I think I'm misunderstanding this question.

Actual genomes from the ancient past.
Blessings.
SR.

 

[gluadys]

I still am not convinced about a single common ancestor, and have yet to see any convincing data to point at one.
It would not surprise me if God did actually intervene somehow in placing the various major groups as explained to us in the Genesis account. After all, it seems pretty amazing (even beyond the realms of credibility) for whole kingdoms to evolve from natural selection/mutations, especially in light of the fact that we have yet to find evidence of jumps across "barriers" higher than a genus level.
SR.

As you keep exploring evolution, you will find that to get a handle on it, you have to correct your understanding of how it works. This is a case in point. Evolution does not call for a jump across any barrier--not even at the genus level. All evolution takes place at the level of the species.

I think one reason people have trouble with this is that in anti-evolution literature, almost the only view of producing new species presented is hybridization and there are clearly limits to producing species in this way.

But the method of producing new species that seems to occur most often in nature is the opposite to hybridization. It is splitting a species into two or more separate groups which diversify over time into new species. This is called cladistic (branching) speciation. This is how you get a common ancestor: by going back along two lineages until you find they both meet at the same species. When they separated they were not a family, order or genus apart. They were only a sub-species apart. So no jump across any barrier was needed, although it looks today like a huge jump would be needed.

 

[Mallon]

All evolution takes place at the level of the species.

Even more specific than that: Evolution takes place at the level of the population.

 

[SoulReason]

As you keep exploring evolution, you will find that to get a handle on it, you have to correct your understanding of how it works. This is a case in point. Evolution does not call for a jump across any barrier--not even at the genus level. All evolution takes place at the level of the species.

I think one reason people have trouble with this is that in anti-evolution literature, almost the only view of producing new species presented is hybridization and there are clearly limits to producing species in this way.

But the method of producing new species that seems to occur most often in nature is the opposite to hybridization. It is splitting a species into two or more separate groups which diversify over time into new species. This is called cladistic (branching) speciation. This is how you get a common ancestor: by going back along two lineages until you find they both meet at the same species. When they separated they were not a family, order or genus apart. They were only a sub-species apart. So no jump across any barrier was needed, although it looks today like a huge jump would be needed.

I understand that, but to try and clarify, how do you get say a plant organism to "branch off" a fish organism, for example. (Just to put it into its most simplistic and unmistakable term).
SR.

 

[Willtor]

I understand that, but to try and clarify, how do you get say a plant organism to "branch off" a fish organism, for example. (Just to put it into its most simplistic and unmistakable term).
SR.

There was no population of fish that ever broke off and evolved into plants. The split between the animal and plant kingdoms happened long before either was recognizable. Sfs or someone may correct me, but I think the division happened before there was multicellular life.

But if you're asking more generally about how a population might divide, it's typically through geographical means. E.g., if there is a population of animals and it divides and the two groups migrate in different directions, and if there is no interbreeding for many generations, it may be that when they _do_ meet again, they are no longer capable of interbreeding.

 

[SoulReason]

As you keep exploring evolution, you will find that to get a handle on it, you have to correct your understanding of how it works. This is a case in point. Evolution does not call for a jump across any barrier--not even at the genus level. All evolution takes place at the level of the species.

Even though, like I said, I am no scholar when it comes to evolutionary theory, it really is rather simple to understand as a mechanism. I find your assumption, and most of those who hold to the ToE , that assumes those who don't accept it have no true grasp of it to be naive.
Case in point, I did not say that evolution is not at the species level, but used the jump across genus comment to illustrate a point. You obviously didn't get it.

I think one reason people have trouble with this is that in anti-evolution literature, almost the only view of producing new species presented is hybridization and there are clearly limits to producing species in this way.

This is another odious assumption of the ToE pusher - that anyone who disagrees with their theory reads anti ToE literature mostly or even exclusively.

But the method of producing new species that seems to occur most often in nature is the opposite to hybridization. It is splitting a species into two or more separate groups which diversify over time into new species. This is called cladistic (branching) speciation.

This is how you get a common ancestor: by going back along two lineages until you find they both meet at the same species. When they separated they were not a family, order or genus apart. They were only a sub-species apart. So no jump across any barrier was needed, although it looks today like a huge jump would be needed.

And quite often there is no observable differences between them and the ability to produce offspring may be lost in a chance mating of the two.
Still, (the next part) it is mere speculative assumption that produces all the kingdoms from single celled organisms from the ancient past - there is an aweful lot of information and difference between them. And this, dear friend, is the biggest hurdle for getting the ToE past the intelligence of everyday Joe. You will have to come up with better science than speculative (albeit educated) guesses. And yes, I am aware that genetics is in its infancy.
SR.

 

[philadiddle]

Even though, like I said, I am no scholar when it comes to evolutionary theory, it really is rather simple to understand as a mechanism. I find your assumption, and most of those who hold to the ToE , that assumes those who don't accept it have no true grasp of it to be naive.
Case in point, I did not say that evolution is not at the species level, but used the jump across genus comment to illustrate a point. You obviously didn't get it.

Maybe you could clarify what you meant by "jumping" across genus. I don't think I got it either.

 

[sfs]

Maybe you could clarify what you meant by "jumping" across genus. I don't think I got it either.

I didn't get it either.

 

[gluadys]

Even though, like I said, I am no scholar when it comes to evolutionary theory, it really is rather simple to understand as a mechanism. I find your assumption, and most of those who hold to the ToE , that assumes those who don't accept it have no true grasp of it to be naive.
Case in point, I did not say that evolution is not at the species level, but used the jump across genus comment to illustrate a point. You obviously didn't get it.

No I didn't. After all the term you used was "evidence of jumps across "barriers" higher than a genus level." And since many people mistakenly think this IS what is the evolution of new species is about, I had no reason to suppose you thought differently.

There are many many times I have been told by creationist objectors to evolution that it doesn't matter how many new species of fruit flies geneticists create in lab experiments, because they are all still fruit flies and the point is to get something out of them that are not fruit flies--a totally new "kind".

It sounded to me that this is the sort of thing you were envisioning too.

This is another odious assumption of the ToE pusher - that anyone who disagrees with their theory reads anti ToE literature mostly or even exclusively.

Oh, you have already indicated a willingness to read evolutionary literature. I see I didn't elaborate enough on the subtlety of what I meant. It is that if one's first exposure to evolution is in anti-evolution literature, one may unknowingly and unconsciously carry over some standard concepts that act as barriers to understanding evolution, even as one reads scientific literature. There will still be a sense of "but how could evolution explain X"? where X stands for a standard concept about evolution that comes from creationist literature and doesn't even really apply as far as the science of evolution is concerned. It is an unconscious process, but can only be undone by determining what the underlying assumption is and clarifying where it is wrong.

The "jumping across barriers" at a higher than species (or as Mallon says--population) level is one such concept. In the actual process of evolution nothing jumps across any barrier. There are no barriers to jump across. One might say the barriers are a post-evolutionary phenomenon. They are generated by the evolutionary process and so are not a barrier to the evolutionary process.

And quite often there is no observable differences between them and the ability to produce offspring may be lost in a chance mating of the two.

Yes, observable differences may not show up until more genetic distance has occurred. I am not sure what you mean by the last part of the sentence.

Still, (the next part) it is mere speculative assumption that produces all the kingdoms from single celled organisms from the ancient past - there is an aweful lot of information and difference between them.

It is an inference from evidence and from theory more than an a priori assumption. Yes, there is a lot of information difference, but there has also been a lot of generations over which to accumulate that difference too.

And this, dear friend, is the biggest hurdle for getting the ToE past the intelligence of everyday Joe. You will have to come up with better science than speculative (albeit educated) guesses. And yes, I am aware that genetics is in its infancy.
SR.

Science IS educated guesses (hypotheses) tested against reality. The important thing is that it is tested against empirical evidence and revised in light of that evidence to be more consistent with observation.

 

[sfs]

Still, (the next part) it is mere speculative assumption that produces all the kingdoms from single celled organisms from the ancient past - there is an aweful lot of information and difference between them. And this, dear friend, is the biggest hurdle for getting the ToE past the intelligence of everyday Joe. You will have to come up with better science than speculative (albeit educated) guesses. And yes, I am aware that genetics is in its infancy.
SR.

The relationships between some of the kingdoms are quite well established. Thus animals, plants and fungi are clearly related genetically, with fungi and animals more closely related than either is to plants. Protists are all over the place, since they are not really a single group. It is only when you get to the three domains -- eukaryotes, prokaryotes and archaebacteria -- that the relationships are speculative (although within the kingdoms there are also plenty of places where the precise order of branching is uncertain).

In any case, this question has very little to do with the objections most people have to evolution. Scientists would be delighted if everyday Joes were arguing about whether all life was descended from one, three or eight ancestors. What people actually argue about is whether humans are related to chimpanzees, not whether both are related to slime molds.

 

[SoulReason]

In any case, this question has very little to do with the objections most people have to evolution. Scientists would be delighted if everyday Joes were arguing about whether all life was descended from one, three or eight ancestors. What people actually argue about is whether humans are related to chimpanzees, not whether both are related to slime molds.

This is one I am not too sure about. It is mostly "proved" these days by T2. However, I see much disagreement on the relationship to chimps in the fact that there would appear to be too little time for the added human brain size to occur. I think we might make many more subsatntial discoveries in genetics yet and so will remain skeptical of the current understanding of T2.
And yes, I am aware it is the ancestor of chimps and humans we are talking about - just to save you the time.
SR.

 

[Assyrian]

Dogs changed size and shape a lot faster than human brains.