Define 'species'

[mark kennedy]

OK, I will bite, exactly HOW do the first three areas of knowledge suggest the latter three conclusions? There are tons of books out there providing the evolutionary models, and you and other young earth creationists have been provided with many explanations on this very forum of those models. All the evidence I have seen shows that the first three areas of knowledge completely falsify the second and third propositions rather than actually support it (again, we have provided all these falsifications over and over on this forum over the years). We have yet to see a single YEC model that explains all the evidence in a way that holds up to scientific scrutiny. As for intelligent design, that has nothing to do with evolution since the leading intelligent design proponent alive today actually accepts full and complete evolution, just sees it as part of the design.

Look I'm not running in circles over a model you have allready rejected a priori. If you have a substantive question on a particular point I'll do what I can to answer it. However, it has been my experience that offering elaborate explanations on multiple points is a waste of time. I have shown you that there is a creationist model in principle and some of the particulars have been pointed out. Other then that I'm not wasting my time building an elaborate model that you aren't even interested in considering.

Yes they are, hominoids are ancestors to apes and humans while hominids are ancestors to humans only.

Good, I am glad you recognize this. It is a good start.

Thats how the words are defined, but thinks for the headtrip, thats very helpfull.

Um, no, it did not have a chimp skull. Chimpanzees were not even around at that time. It had a very ape-like skull, it is true.

The skull was not signifigantly larger then that of a modern chimp and it bears a strong resembelance to the semi bipedal pan paniscus. What you are looking at is probably the ancestor to the modern pan paniscus. Dont you ever actually research anything in your posts.

What Leakey and others found in southern Africia was exactly what they wanted find, human ancestors. Who cares that they were apes transposing into chimps the evolution of humans from other primates was too important to be bothered with little details like this. Let me clue you in on how these elaborate illusions and shadows are cast upon the wall. Most of the diversity of living creatures are found in lush areas like rain forests and jungles. What we are looking at is a racemic mixture as the larger ape was scaling down to adapt to more limited resoures then they had in the antidelving period.It might also interest you to know that over time most species are scaling down.

Thus, making it NOT an ape, but a hominid, by definition. Apes are not bipedal.

No they are not but many of the descendants are like the pygmy chimpanzee. You are going to have to think outside the box and quite watching the shadows they are throwing on the wall here. Leaky like Darwin is amplifying superficial simularities to create the illusion of transmutation that simply doesn't happen on the scale they would have you believe. Fossils are fragmentary evidence that supposedly show ape ancestors grew smaller bodies while growing larger brains. One other distinction between apes and humans is the thumb, but you probably would never have realized that writting anticreationist posts.

No, since they were three different specimens of the same species.

This whole species is based on the compilation of those three specimans, including a footprint. This is how they determined that this was a species and the other fragmentary fossils were twisted to fit into this highly speculative hypothesis that has never been demonstrated.

Well, except for the bipedal part, and a collection of other differences, sure. The idea that there are lots of similarities between these species is one of the whole points.

Anytime there is a homological simularity then it is evidence of a common ancestor. When they find a difference then it is a morphologic evolutionary change, this isn't even a good hypothesis since it cannot be falsified. Is an a priori assumption of naturalistic methodology with regards to our origins. Keep watching the shadows on the wall and you will start to see things that aren't there.

Well, no, it is not an ape, because it is bipedal. Apes are not bipedal. Second, do you really think these guys can’t tell the difference between a chimp and another species? If you honestly and truly believe that this fossil is a chimp, I am afraid I have lost all respect for your ability to rationally review the evidence and this conversation might as well come to an end.

You are assuming that the conversation ever got started in the first place. When you have an ambiquise definition for the central point of species and there are no clear criteria for determining what is a distinct species in natural history a transition from the ape to the chimp can easily be mistaken for a human ancestor, which is exactly what happened. Leaky did the same thing determining the homo habilis, even though the cranium was below the lower limit for the homo classification he found some tools in the same geologic horizon, if thats what they actually were. Thus the name 'handy man', it was ironic that Homo rudolfensis was thought to be the ancestor of H. habilis but now it would seem that they are contemporary to the handy man. Now of course it is automatically assumed that it must be ancestoral to one of the other homo species.

Again, present a comprehensive model that works with the existing evidence and we would have something to talk about. You have yet to do this, or even explain exactly how far back your initial "kinds" go. You seem to be working on a loose theory that you hold to because it fits your theology and are then massaging the facts around to fit that loose theory. When you have something solid, feel free to present it. So far, all the YEC scientists have utterly failed to present anything that has not been falsified by the evidence, but maybe you will have more success.

Creationist did not make the postitive statements requiring proof. Lets sum up shall we, the definition for species in the synthesis is an organism or population that interbreeds with its own 'kind'. No problem here except there are all these fossils that must represent ancestory due to evolutionary morphology. There is no genetic, biologic or naturalistic methodolgy that is testable in natural science (as opposed to natural history) that can be positivly identified as the mechanism for these transmutations.

Strange as it may seem I am learning far more watching the evolutionary apologist attack their own philosophical underpinnings then I ever could reading creationists. I have watch Darwin, Mayr and Gould dismissed, ignored and refused even though they represent the cutting edge of evolutionary thought. There is such a premium put on assailing creationists on here that you guys never stop to think you may well be attacking your own.

You have demonstrated that you are cluless as to what naturalistic methodolgy is, how distinctive species are established in natural evidence, life adapts and develops in ecosystems over time, the philosophy of science that you are pretending to defend. Thanks for the shadow puppet show and lets do this again real soon.

The only thing I was trying to do is to figure out how species is defined in modern biology and compare it to the Biblical word for 'kind'. This was all too easy, then there were a number of pedantic rants about species in natural history and what has happened is that I finally figured out how species are determined there as well. That was a big bonus, all I had to do was read between the lines and do a couple of google searches. This is so much fun, I can't wait to tell them about this in the creation forum.

 

[Vance]

" Look I'm not running in circles over a model you have allready rejected a priori. If you have a substantive question on a particular point I'll do what I can to answer it. However, it has been my experience that offering elaborate explanations on multiple points is a waste of time. I have shown you that there is a creationist model in principle and some of the particulars have been pointed out. Other then that I'm not wasting my time building an elaborate model that you aren't even interested in considering."

Without a model that works, you have nothing except theology disguised as science. The truth is that you have some vague notion of what you want to be true, but can not articulate details without it running afoul of the actual evidence. The scientific community has presented its model and it has stood for 150 years: common descent through the mechanics of evolution.

Dozens of Creation Scientists (I can't even say hundreds since I don't think there are that many) have been trying to put together a model that will withstand scrutiny for a very long time, but have failed to do so. Falsified by simple scientific principals every time. The reason is simple. They are starting with a theologically-based position and seeking out scientific support for that position and trying to find ways to destroy all the evidence that counters that theologically-based position. This does not make for sound science.

You said you were willing to provide specific details if asked, though, so here is one question: what are the basic groups of "kinds" and when did they start their amazing diversification? The "what" should be easy if the "kinds" are so obvious as to provide a grounds for refusal to believe in common descent.

As for disagreements with Mayr and Gould, you are either not understanding or are being purposefully deceitful in your characterization. Nothing in my disagreements with them go to the "underpinnings" of anything, much less evolution. Abiogenesis is NOT an underpinning of evolution, no matter how much you would like to make it so.

 

[mark kennedy]

" Look I'm not running in circles over a model you have allready rejected a priori. If you have a substantive question on a particular point I'll do what I can to answer it. However, it has been my experience that offering elaborate explanations on multiple points is a waste of time. I have shown you that there is a creationist model in principle and some of the particulars have been pointed out. Other then that I'm not wasting my time building an elaborate model that you aren't even interested in considering."

Without a model that works, you have nothing except theology disguised as science. The truth is that you have some vague notion of what you want to be true, but can not articulate details without it running afoul of the actual evidence. The scientific community has presented its model and it has stood for 150 years: common descent through the mechanics of evolution.

Dozens of Creation Scientists (I can't even say hundreds since I don't think there are that many) have been trying to put together a model that will withstand scrutiny for a very long time, but have failed to do so. Falsified by simple scientific principals every time. The reason is simple. They are starting with a theologically-based position and seeking out scientific support for that position and trying to find ways to destroy all the evidence that counters that theologically-based position. This does not make for sound science.

You said you were willing to provide specific details if asked, though, so here is one question: what are the basic groups of "kinds" and when did they start their amazing diversification? The "what" should be easy if the "kinds" are so obvious as to provide a grounds for refusal to believe in common descent.

As for disagreements with Mayr and Gould, you are either not understanding or are being purposefully deceitful in your characterization. Nothing in my disagreements with them go to the "underpinnings" of anything, much less evolution. Abiogenesis is NOT an underpinning of evolution, no matter how much you would like to make it so.

Like I said you are clueless of the philosophical underpinnings of naturalistic methodology. There is no need to build an elaborate antithesis, the genuine article of natural science is neutral in this convoluted controversy. Honestly, I havn't done the math as far as the exponential growth of populations or the limits of geologic isolation, nested hiearchies or speciation. Of course that was never nessacary in this thread since all I was looking for was a good working definition for species that was consistant with creationist thought. You have obviously confused evolutionary biology with naturalistic methodology and resorted to baseless insinuations and allegations of alterior motives. Its called projection and its telling how people tend to condemn in others the thing they most fear about themselves.

 

[Loudmouth]

Like I said you are clueless of the philosophical underpinnings of naturalistic methodology.

And those underpinnings are . . .

1. Natural phenomena are caused by natural mechanisms.

2. Theories should be based on empirical data.

The reasons for using methodolgical naturalism is that it works. Unless you can show us one theory in use today that depends on the input of a supernatural deity we will continue to use methodological naturalism. It has been the experience of man that whenever he inserts a deity into a gap in our knowledge that gap tends to be filled by a natural mechanism. Methodological supernaturalism has never worked and so it was dropped.

Of course that was never nessacary in this thread since all I was looking for was a good working definition for species that was consistant with creationist thought.

We would be happy with a definition that is consistent with the evidence.

You have obviously confused evolutionary biology with naturalistic methodology and resorted to baseless insinuations and allegations of alterior motives. Its called projection and its telling how people tend to condemn in others the thing they most fear about themselves.

Methodological naturalism was used to derive the theory of evolution, just like other theories in science including the theory of gravity, the germ theory of disease, and quantum mechanics.

 

[mark kennedy]

And those underpinnings are . . .

1. Natural phenomena are caused by natural mechanisms.

2. Theories should be based on empirical data.

Neither the natural phenomena of the empirical data accounts for the nonconstancy of species. Now while immutablity was rightfully discarded this is not the same thing as special creation. Immutability was an Aristolean concept that was sythesised into both theology and natural science by St Thomas Aquainas. Ever hear of the Protestant reformation? It was the basis for the Scientific Revolution, not naturalistic methodology. Rome had become exclusivly secular in its orientation and political philosophy and it was distorting and censoring the findings of natural science so Rome was striped of authority in both areas.

The reasons for using methodolgical naturalism is that it works. Unless you can show us one theory in use today that depends on the input of a supernatural deity we will continue to use methodological naturalism. It has been the experience of man that whenever he inserts a deity into a gap in our knowledge that gap tends to be filled by a natural mechanism. Methodological supernaturalism has never worked and so it was dropped.

All that is really important is that one model corrospond to the data to the exclusion of the other. There is no such thing as methodological supernaturalism and its the same strawman as immutability that doesn't represent the creationist model. Just as it is a human tendancy to fill in a deity into a gap in natural history naturalistic methodology does the same thing. In the causative chain of events there should be no weak links and any viable alternative should be at least considered. The only way this does not happen is if it is rejected apriori as it is with naturalistic methodology. What science is focused on is what actually happened historically and naturalistic methodology is by definition atheistic at its premise.

We would be happy with a definition that is consistent with the evidence.

Again, the definition that is most often used is that species is a gereral term to describe organisms that interbreed and produce fertile offspring accoding to their 'kinds'. This is identical to the idea communicated in the Genesis account.

Methodological naturalism was used to derive the theory of evolution, just like other theories in science including the theory of gravity, the germ theory of disease, and quantum mechanics.

Wrong, evolution is simply the change of populations over time. No one in the creationist camp is suggesting that species have not evolved in the strictly scientific sense of the term. It is the extent to which naturalistic methodology can be used to account for changes and the emergence of new species. In the universal common ancestor model it is only natural mechanisms that are given any real consideration, all others are rejected a priori. In other words the actual evidence is bent to fit the premise rather then the other way around. This isn't about the creationist vs the evolutionist model its the universal common ancestor model vs the multiple common ancestor model of the archetypes being fully formed as an act of God's soverign will and descending from original forms as an ongoing expression of divine providence. It is only when providence is rejected as a natural law, or natural law is itself dismissed, that this becomes untenable for the creationist. This is exactly what happened in evolutionary biology in modern biology, its philosophical underpinnings are exclusivly naturalistic dispite the laws of science, not because of them.

I have offered explicit proof that this is indeed what happened and not a single shred of substantive proof has been offered to the contrary.

 

[Jet Black]

I don't care if you like what they have to say, that does not mean they are being dishonest.

of couurse you are right. however their misrepresentation of evolution makes them dishonest.

I never said that there weren't only that for the most part the are deletreous or harmfull.

so sometimes they aren't. then why can these beneficial mutations not accumulate?

 

[mark kennedy]

of couurse you are right. however their misrepresentation of evolution makes them dishonest.

They just don't accept the universal common ancestor model, that does not make them dishonest. Now I have no problem with you saying they are wrong, a lot of people would agree with that. But to call them dishonest because they don't support a single common ancestor model...thats going too far.

so sometimes they aren't. then why can these beneficial mutations not accumulate?

Mainly because mutations are rarely beneficial and hardly qualify as a demonstrated mechanism for the universal common ancestor model. What reason do we have to believe that they do accumulate?

 

[Ondoher]

Mainly because mutations are rarely beneficial and hardly qualify as a demonstrated mechanism for the universal common ancestor model. What reason do we have to believe that they do accumulate?

Well, there is always the primary literature:

Modular assembly of novel genes from existing genes has long been thought to be an important source of evolutionary novelty. Thanks to major advances in genomic studies it has now become clear that this mechanism contributed significantly to the evolution of novel biological functions in different evolutionary lineages. Analyses of completely sequenced bacterial, archaeal and eukaryotic genomes has revealed that modular assembly of novel constituents of various eukaryotic intracellular signalling pathways played a major role in the evolution of eukaryotes.

Patthy, L. (2003). “Modular assembly of genes and the evolution of new functions.” Genetica 118(2-3): 217-231.

Genome data have revealed great variation in the numbers of genes in different organisms, which indicates that there is a fundamental process of genome evolution: the origin of new genes. However, there has been little opportunity to explore how genes with new functions originate and evolve. The study of ancient genes has highlighted the antiquity and general importance of some mechanisms of gene origination, and recent observations of young genes at early stages in their evolution have unveiled unexpected molecular and evolutionary processes.

Long, M., Betran, E., Thornton, K. and Wang, W. (2003). “The origin of new genes: glimpses from the young and old.” Nat Rev Genet 4(11): 865-875.

Rapid adaptive fixation of a new favorable mutation is expected to affect neighboring genes along the chromosome. Evolutionary theory predicts that the chromosomal region would show a reduced level of genetic variation and an excess of rare alleles. We have confirmed these predictions in a region of the X chromosome of Drosophila melanogaster that contains a newly evolved gene for a component of the sperm axoneme.

Nurminsky, D., Aguiar, D. D., Bustamante, C. D. and Hartl, D. L. (2001). “Chromosomal effects of rapid gene evolution in Drosophila melanogaster.” Science 291(5501): 128-130.

It isn't like the evolution of new genes is some mystery. It is quite well studied.

P.S. I have links to all of these on PubMed but I cannot trick this thing into letting me post the links, even as text.

 

[kingreaper]

Mainly because mutations are rarely beneficial and hardly qualify as a demonstrated mechanism for the universal common ancestor model. What reason do we have to believe that they do accumulate?

Think of beneficial mutations like prime numbers, at the begginning there are tons, as more things are beneficial, and slowly the amount that are prime (benificial) decreases, until you'll only get one out of every 1000 numbers, but they still keep adding up

 

[Tomk80]

They just don't accept the universal common ancestor model, that does not make them dishonest. Now I have no problem with you saying they are wrong, a lot of people would agree with that. But to call them dishonest because they don't support a single common ancestor model...thats going too far.

Bullocks. Whether or not they accept the universal common ancestor model doesn't come into it. They only tell half of the story, that's what makes them dishonest. Again, time and chance is not the same as time, chance and selection. That they fail to mention selection makes them dishonest.

 

[caravelair]

Mainly because mutations are rarely beneficial

but that's not really relevant, because deleterious mutations would not accumulate. it only matters that beneficial mutations do exist, which they clearly do.

and hardly qualify as a demonstrated mechanism for the universal common ancestor model.

well, mutations themselves would not be the mechanism. mutations merely provide the genetic variations which evolution acts on.

What reason do we have to believe that they do accumulate?

what reason do we have to believe that they don't accumulate? mutations change the genetic code, and these mutations are then passed on. if an organism inherits a new trait caused by a mutation in one of it's ancestors, what would prevent it, or it's offspring, from also having a beneficial mutation of it's own? this would be accumulation, no?

 

[Pete Harcoff]

Mainly because mutations are rarely beneficial and hardly qualify as a demonstrated mechanism for the universal common ancestor model. What reason do we have to believe that they do accumulate?

If a beneficial mutation can become fixed in a population, then by definition they can accumulate. Think "recursion".

 

[mark kennedy]

"Modular assembly of novel genes from existing genes has long been thought to be an important source of evolutionary novelty. Thanks to major advances in genomic studies it has now become clear that this mechanism contributed significantly to the evolution of novel biological functions in different evolutionary lineages. Analyses of completely sequenced bacterial, archaeal and eukaryotic genomes has revealed that modular assembly of novel constituents of various eukaryotic intracellular signalling pathways played a major role in the evolution of eukaryotes."

Patthy, L. (2003). “Modular assembly of genes and the evolution of new functions.” Genetica 118(2-3): 217-231.

All this really demonstrates is that extracellular signalling proteins are produced. Just as a creationist accepts that there is microevolution in the form of adaptation, this kind of thing causes no real problems.

"Genome data have revealed great variation in the numbers of genes in different organisms, which indicates that there is a fundamental process of genome evolution: the origin of new genes. However, there has been little opportunity to explore how genes with new functions originate and evolve. The study of ancient genes has highlighted the antiquity and general importance of some mechanisms of gene origination, and recent observations of young genes at early stages in their evolution have unveiled unexpected molecular and evolutionary processes."

Long, M., Betran, E., Thornton, K. and Wang, W. (2003). “The origin of new genes: glimpses from the young and old.” Nat Rev Genet 4(11): 865-875.

"They come right out and say that there has been little opportunity how they originate and evolve. You guys seem to be under the impression that I don't think that evolution occurs. I never said that, its the universal common ancestor model that I think is stretching the evidence well beyond the breaking point. "

"Rapid adaptive fixation of a new favorable mutation is expected to affect neighboring genes along the chromosome. Evolutionary theory predicts that the chromosomal region would show a reduced level of genetic variation and an excess of rare alleles. We have confirmed these predictions in a region of the X chromosome of Drosophila melanogaster that contains a newly evolved gene for a component of the sperm axoneme."

Nurminsky, D., Aguiar, D. D., Bustamante, C. D. and Hartl, D. L. (2001). “Chromosomal effects of rapid gene evolution in Drosophila melanogaster.” Science 291(5501): 128-130.

Correct me if I'm wrong, isn't this a study of fruitflys, I have no real problem with dramatic changes in their short gene sequences being changed dramaticly. The more complex the organism becomes the more harmfull major changes in the genes would be.

 

[mark kennedy]

but that's not really relevant, because deleterious mutations would not accumulate. it only matters that beneficial mutations do exist, which they clearly do.

Benificial would be the exception not the rule, in fact they are very rare even if the are occasionally retained. This doesn't represent a demonstrated mechanism for macroevolution.

well, mutations themselves would not be the mechanism. mutations merely provide the genetic variations which evolution acts on.

The gene load has to be signifigantly altered with genes actually added to or removed from the gene flow. Now the random variations of inheritable traits does not account for macroevolution. Most of the algorithims that supposedly represent the evolutionary process are very limited changes. You have an awfull lot of changes accounted for with some very minor changes.

what reason do we have to believe that they don't accumulate? mutations change the genetic code, and these mutations are then passed on. if an organism inherits a new trait caused by a mutation in one of it's ancestors, what would prevent it, or it's offspring, from also having a beneficial mutation of it's own? this would be accumulation, no?

It doesn't really matter what I would do with a backhoe if I had one, if I only have a spade shovel then that is what I have to work with.

 

[mark kennedy]

If a beneficial mutation can become fixed in a population, then by definition they can accumulate. Think "recursion".

That is a really big if Pete, to say nothing of the fact that recursion is largely a matter of conjecture. At best it represents an hypothesis that has yet to be demonstrated.

 

[Ondoher]

Patthy, L. (2003). “Modular assembly of genes and the evolution of new functions.” Genetica 118(2-3): 217-231.

All this really demonstrates is that extracellular signalling proteins are produced. Just as a creationist accepts that there is microevolution in the form of adaptation, this kind of thing causes no real problems.

Long, M., Betran, E., Thornton, K. and Wang, W. (2003). “The origin of new genes: glimpses from the young and old.” Nat Rev Genet 4(11): 865-875.

They come right out and say that there has been little opportunity how they originate and evolve. You guys seem to be under the impression that I don't think that evolution occurs. I never said that, its the universal common ancestor model that I think is stretching the evidence well beyond the breaking point.

Nurminsky, D., Aguiar, D. D., Bustamante, C. D. and Hartl, D. L. (2001). “Chromosomal effects of rapid gene evolution in Drosophila melanogaster.” Science 291(5501): 128-130.

Correct me if I'm wrong, isn't this a study of fruitflys, I have no real problem with dramatic changes in their short gene sequences being changed dramaticly. The more complex the organism becomes the more harmfull major changes in the genes would be.

Sounds to me like you are agreeing that evolution can produce not only beneficial mutations, but novel genes. I fail to see the problem here. What processes do you propose would prevent the accumulation of such changes from producing eventual large scale morphological and behavioral differences?

 

[Ondoher]

The actual evidence is the skull of a chimp, that was unusually bipedal, not unlike the pygmy chimpanzee Pan paniscus. I think its Johnson and Leaky that are being dishonest, not Parker and Morris. So there

WAH!
What does "unusually bipedal" mean? Are you claiming that the specific derived characteristics of Lucy, which makes her an obvious bipedal ape, are just the result of natural variation in the chimpanzee line? That's nuts.

Lucy is a perfect example of a transitional fossil. Here is how it works: If evolutuon is true, then we would expect to find the fossils of taxa that show the emergence and development of diagnostic traits intermediate between two groups of species for whom there is a proposed evolutionary relationship.

There is a proposed evolutionary relationship between apes and humans. That means that we expect to find the emergence and development of those traits that separate humans fom the rest of the apes. These traits are bipedalism, a large brain, small canines, a flat face, a chin, a large frontal lobe, reduced brow ridges, etc.

What is interesting is that prior to finding these fossils, scientists always thought that a large brain was the first trait to develop in our ancestors. Evidence, however, has shown them wrong. It was bipedalism.

Lucy is not the only fossil that shows bipedalism in the hominid record, she is just the most explicit, with a well preserved pelvis, knees and feet. Other fossils, like Ardipithicus ramidus, and the recently reported find from Dr. Robert Eckhardt et. al. push the evidence back further in time:

In present day chimps and gorillas, the thicknesses in the upper and lower parts of that bone are approximately equal. In modern humans, the bone on top is thinner than on the bottom by a ratio of one to four or more. The ratio in this fossil is one to three.
The ratio in the fossil is evidence for transition to an upright posture and habitual bipedal gait the researchers argue. In addition, Eckhardt notes, because walking upright is the essential mark of a hominid, the ratio is functional evidence that the bones fossilized at Lukeino were from hominids.

This new find pushes the inception of bipedalism back to about six million years, three million years earlier than Lucy.

No, Lucy is not some oddly bipedal chimp. You would not find the very specific adaptations for bipedalism amongst the normal genetic variations within a population of chimps. Lucy appears exactly where and when such a transitional should be found.

 

[mark kennedy]

Sounds to me like you are agreeing that evolution can produce not only beneficial mutations, but novel genes. I fail to see the problem here. What processes do you propose would prevent the accumulation of such changes from producing eventual large scale morphological and behavioral differences?

The limited gene pool would be the most obvious, then there is the tendancy of the DNA to repair changes caused by mutations. I don't really have a problem with evolution in a limited sense but for the universal common ancestor model to work you have to have a demonstrated that accounts for countless microevolutionary changes. It is intellectually dishonest to to make a postitive statement for something as ubiguitous as evolution of all living organisms from single cell organisms and then defened it by saying, prove its not possible. Its not a fact in science untill it is demonstrated, in fact when forming a hypothesis you have to determine how it is falsifiable or its just idle speculation.

 

[Ondoher]

The limited gene pool would be the most obvious

What limited gene pool. We just agreed evolution can produce novel genes. That increeases the gene pool.

then there is the tendancy of the DNA to repair changes caused by mutations.

We already agreed that evolution can generate new genes, this doesn't seem applicable.

I don't really have a problem with evolution in a limited sense but for the universal common ancestor model to work you have to have a demonstrated that accounts for countless microevolutionary changes. It is intellectually dishonest to to make a postitive statement for something as ubiguitous as evolution of all living organisms from single cell organisms and then defened it by saying, prove its not possible. Its not a fact in science untill it is demonstrated, in fact when forming a hypothesis you have to determine how it is falsifiable or its just idle speculation.

The evidence for comon ancestry is so vast that science refers to it as the "fact of evolution". Some form of evolution was widely proposed even prior to On the Origins of Species, because of that evidence. The Modern Synthesis merely provides the mechanisms.

 

[mark kennedy]

WAH!
What does "unusually bipedal" mean? Are you claiming that the specific derived characteristics of Lucy, which makes her an obvious bipedal ape, are just the result of natural variation in the chimpanzee line? That's nuts.

Lucy is a perfect example of a transitional fossil. Here is how it works: If evolutuon is true, then we would expect to find the fossils of taxa that show the emergence and development of diagnostic traits intermediate between two groups of species for whom there is a proposed evolutionary relationship.

There is a proposed evolutionary relationship between apes and humans. That means that we expect to find the emergence and development of those traits that separate humans fom the rest of the apes. These traits are bipedalism, a large brain, small canines, a flat face, a chin, a large frontal lobe, reduced brow ridges, etc.

What is interesting is that prior to finding these fossils, scientists always thought that a large brain was the first trait to develop in our ancestors. Evidence, however, has shown them wrong. It was bipedalism.

Lucy is not the only fossil that shows bipedalism in the hominid record, she is just the most explicit, with a well preserved pelvis, knees and feet. Other fossils, like Ardipithicus ramidus, and the recently reported find from Dr. Robert Eckhardt et. al. push the evidence back further in time:
This new find pushes the inception of bipedalism back to about six million years, three million years earlier than Lucy.

No, Lucy is not some oddly bipedal chimp. You would not find the very specific adaptations for bipedalism amongst the normal genetic variations within a population of chimps. Lucy appears exactly where and when such a transitional should be found.

"The position of A. afarensis in the phylogeny of early humans is under debate. Many feel that it is ancestral to the east African "robust" early humans, and possibly to all robust forms. Additionally, A. afarensis is proposed as the ancestor to later Homo. Yet, research now suggests that A. africanus might be ancestral to later Homo."

The phylogeny of this fossil is not clearly demonstrated in fact its skull(430cc) is not that different from the modern chimpanzee. "From this, it is clear that there are many significant difference between A. afarensis and its ape predecessors, one of which is crucial to later human evolution, bipedality."

The crucial demonstration here has to be the bipedality, here is how they determined that a transition was underway. It is actually a composite of three specimans, "composite reconstruction based on several specimens, the famous Laetoli footprints, and the AL 129".

This is based on questionable phylogeny and peicemeal forensics. This is only one example of how these supposed transitions are fitted together to fit the philosophical premise.

"OH 62 has raised more questions than she has answered. Where did the later species of Homo come from? Cranially, Homo habilis is more similar to later Homo, and many consider this to be the true lineage. But the emergence of early humans with modern body proportions in a relatively short time, while not impossible, gives some researchers cause for concern, and they look to other lineages, such as Homo rudolfensis. (Click to see a representation of the two implied phylogenies)

Additionally, this confuses the evolution of early humans at the level of Australopithecus afarensis and A. africanus. Which lineage gave rise to later Homo? The body proportions of A. africanus have been found to be more ape-like than the earlier A. afarensis. Paradoxically, this may place A. africanus as the ancestor of Homo-- if, in fact, the early members of our genus had ape-like body proportions like OH 62."

More Questions then answers

In order for a species to be determined in natural history there has to be a defining speciman. The fossil evidence represents scarce and highly peicmeal forensics.