Human Evolution

[Jose]

jcrawford and I have been having some interesting discussions in other threads, which have led to the notion that we really need a thread on human evolution. So, here it is.

The Rules
We want to work from data. Data that is discussed must be accessible in the scientific literature. Personally, I would prefer the peer-reviewed literature, because, as those of us in science know all too well, the peer reviewers are usually one's competitors. Thus, they are typically extremely critical of what we write.

Any other information that is brought to bear must also be accessible to everyone. Where requested, direct quotes from the sources will be important.

The questions for discussion

1. What is the current best understanding of human origins?

2. What "confounds" are there in the interpretation of data?

3. Given that there is always genetic diversity within populations, how easily can we assign hominid fossils to different groups? Here, the term "form-species" is probably most useful, referring to similar fossils with similar forms, but in the absence of information on the capacity for interbreeding. In many cases, different form-species are different species (fossil trees vs fossil insects), but sometimes they are not (fossil leaves vs fossil roots of the same tree).

4. Does information based on fossil data mesh with information based on genetic data? The true history must be genetically feasible. The fossils must have been left by individuals who were produced by normal genetic methods. To be valid, any explanation of origins must incorporate both fossil and genetic data.

5. What are the parts of human history that are most at odds with (some) Christian views, and what suggestions can we offer for reaching a reconciliation?

I will begin by posting the following genetic data, which is pictorial representation of the differences and similarities in mitochondrial DNA sequence of a whole bunch of people. Relative difference/similarity is proportional to the lengths of the vertical lines. Horizontal lines merely separate the vertical lines so we can see them.

How do we interpret these data?

[If appropriate, I will edit this post to ensure that the OP of this thread lists the important questions.

[jcrawford]

But, you are looking at only one small part of the human-evolution story here. Your original issue, as I recall (fuzzily now), was that a species cannot be the ancestor of another species if the two species live contemporaneously.

My contention would be that when two or three neo-Darwinist 'species' are demonstrated by the human fossil record to have not only lived contemporaneously, but also to have lived and been buried together geographically in the same location, as the Pit of Bones excavation site in Spain so clearly indicates, that there is no indication of any human evolution from one 'species' into another. Rather does such a recent fossil site discovery show that what neo-Darwinist race theorists call "different and separate human species" are nothing more than racial variants of the one and only human race and species.

[jcrawford]

The Smithsonian site shows H. erectus, H. sapiens, and H. neanderthalensis as contemporaneous for some period of time. Being contemporaneous does not prevent H. sapiens or H. neanderthalensis from being descendents of H. erectus, or being a sibling-species with H. erectus, both derived from H. ergaster.

According to the fossil record H. erectus has been around for almost 2 million years and is contemporaneous with all subsequent neo-Darwinist 'species,' if not 'species' progenitors such as H. ergaster, rudolphensis, and habilis themselves. Human fossils, in and of themselves, give no indication of their 'species' or of having evolved from former human 'species.' It is only when they are manipulated and arranged in a progressively evolutionist order of 'species' gradation between human and ape fossils that the mirage (or reconstructed movie) of human evolution emerges from the pictorial representations of the skulls.

One might note, by the way, that the Smithsonian "tree" is incomplete, inasmuch as we don't have enough fossils to fill in the blanks.

According to Lubenow, there are over 8,000 human fossils on record to choose from in order to create an evolutionist illusion. All future discoveries will be allotted their respective place in the evolutionist order of human origins.

There's a year or two between H. ergaster's youngest fossil and H. heidelbergensis's oldest; this gap may eventually be filled in as we find more fossils.

A year or two! More like a quarter million, since ergaster-like fossils show up in China as H. erectus (Peking Man) as late as 300Kya and in Australia as recently as 10Kya.

Maybe the links between parts of the tree will have to be estimated differently when that happens. We'll have to wait and see.

Yes, I forgot to include "maybe, links, parts, tree, estimated, different, and wait and see" in the neo-Darwinist lexicon of evolutionist terminology.

[jcrawford]

OK. Here's an interpretation:

1. There is greater diversity in Africa than elsewhere suggesting that African populations have been around longer.
2. The diversity is "deeper" in Africa than elsewhere (i.e. the vertical lines are longer), indicating that more mutations have occurred, further suggesting that African populations are older.
3. Non-African populations are very closely related to one group of Africans suggesting that it was this group, and not the others, that migrated to Europe, Asia, and the rest of the world.
4. It is possible to determine the root of the tree indicating that there are other species that are genetically-related to humans. Genetic relationship reflects "being part of the same family," with common great-great-great etc grandparents.
5. The species with the closest DNA sequence to humans is chimps suggesting that they are our "cousins" and our nearest relatives in our family tree.

If there are aspects of this interpretation with which you disagree, you'll need to find flaws in the logic. For example, you were not among those whose DNA was used (I don't know, but statistical likelihood is low), so you will have to extrapolate from this interpretation to place yourself on the tree. Maybe you're on a different tree altogether, but I doubt it.

We're seven or eight pages into the debate already and you haven't associated one human gene with one single fossil. You did say something about the fossil record being compliant with genetic interpretations, didn't you?

I did say something like that. Now, the way embryology works, there is no single gene that is responsible for any single trait in skull development (so far as I know). Many cooperate. Still, we can link the genetic tree we've been discussing to fossil data as follows:

1. The most ancient hominid fossils are from Africa
2. The oldest modern human fossils are from Africa
3. Archeological data indicate that humans populated different continents at different times,with Africa being first, and South America being last.
4. DNA sequence data indicate that non-Africans are closely related to one group of Africans (parallel to #3)
5. DNA sequence data indicate that African populations are older than non-African populations (parallel to #2)
6. DNA sequence data indicate that the species most closely related genetically to humans is chimps
7. Known mechanisms of DNA chemistry and inheritance suggest that any new mutation (genetic variation) will first arise in one individual, and can become common among many individuals of a population only by being passed on to offspring that are more "reproductively capable" than others, and that this must occur over many generations
8. Populations that are split into smaller subpopulations show a pattern of subsequent genetic variation in which each subpopulation acquires mutations, but because the mutations of one subpopulation are not the same as those of the other, the two subpopulations acquire different genetic diversity
9. The longer subpopulations are separated, the greater the genetic differences between them become (mechanistically relates 4 and 5 with 1 and 2; provides a mechanism for the diversification of different groups of hominids; provides a mechanism for the development of different characteristics between chimps and humans, even if they are descendents from a common ancestor)

Ripley's "Believe It Or Not?"

You may say this of the above. However, "believe" is not a relevant word here. The question is whether the data lead to the conclusions, and whether alternative explanations can be ruled out. What are the flaws in the logic, and can we justifiably set them aside? (e.g. the tree is only a small sample of people; is it valid to extrapolate? Perhaps not...but the conclusions regarding the particular sample remain valid--including the "deeper" variation in Africa and the remarkable similarity among non-Africans in the sample.) The "rule" with Faith is whether or not we believe something; here, we have data, for which the game is interpretation. We often get conclusions we don't believe, or don't want to believe, but nonetheless feel compelled to accept them because we can't see any way out of it. Other times, we get conclusions we believe quite happily, but which turn out to be wrong when we consider additional information. So, let's set aside "belief" and ask, quite nerdily, whether the data justify the conclusions. We can philosophize on the implications after we determine whether we've got a valid interpretation.

draft

[jcrawford]

OK. Here's an interpretation:

1. There is greater diversity in Africa than elsewhere suggesting that African populations have been around longer.
2. The diversity is "deeper" in Africa than elsewhere (i.e. the vertical lines are longer), indicating that more mutations have occurred, further suggesting that African populations are older.
3. Non-African populations are very closely related to one group of Africans suggesting that it was this group, and not the others, that migrated to Europe, Asia, and the rest of the world.
4. It is possible to determine the root of the tree indicating that there are other species that are genetically-related to humans. Genetic relationship reflects "being part of the same family," with common great-great-great etc grandparents.
5. The species with the closest DNA sequence to humans is chimps suggesting that they are our "cousins" and our nearest relatives in our family tree.

If there are aspects of this interpretation with which you disagree, you'll need to find flaws in the logic. For example, you were not among those whose DNA was used (I don't know, but statistical likelihood is low), so you will have to extrapolate from this interpretation to place yourself on the tree. Maybe you're on a different tree altogether, but I doubt it.

We're seven or eight pages into the debate already and you haven't associated one human gene with one single fossil. You did say something about the fossil record being compliant with genetic interpretations, didn't you?

I did say something like that. Now, the way embryology works, there is no single gene that is responsible for any single trait in skull development (so far as I know). Many cooperate. Still, we can link the genetic tree we've been discussing to fossil data as follows:

1. The most ancient hominid fossils are from Africa
2. The oldest modern human fossils are from Africa
3. Archeological data indicate that humans populated different continents at different times,with Africa being first, and South America being last.
4. DNA sequence data indicate that non-Africans are closely related to one group of Africans (parallel to #3)
5. DNA sequence data indicate that African populations are older than non-African populations (parallel to #2)
6. DNA sequence data indicate that the species most closely related genetically to humans is chimps
7. Known mechanisms of DNA chemistry and inheritance suggest that any new mutation (genetic variation) will first arise in one individual, and can become common among many individuals of a population only by being passed on to offspring that are more "reproductively capable" than others, and that this must occur over many generations
8. Populations that are split into smaller subpopulations show a pattern of subsequent genetic variation in which each subpopulation acquires mutations, but because the mutations of one subpopulation are not the same as those of the other, the two subpopulations acquire different genetic diversity
9. The longer subpopulations are separated, the greater the genetic differences between them become (mechanistically relates 4 and 5 with 1 and 2; provides a mechanism for the diversification of different groups of hominids; provides a mechanism for the development of different characteristics between chimps and humans, even if they are descendents from a common ancestor)

http://www.sciencedaily.com/releases/20 ... 194453.htm

http://www.sciencedaily.com/releases/20 ... 071610.htm

As previousl posted by myself, the unfounded assumptions upon which interpretations and conclusions about genetic data, human relationships and human origins are premised are:

1. That mtDNA is passed on only by the mother. - refuted by John Maynard Smith, Richard Hudson and Henry Harpending. (Lubenow)

2. That mtDNA mutations are regular and serve as a molecular "clock." - refuted by Neil Howard. (Lubenow)

3. That mtDNA can be used to dertermine human and primate relationships. - refuted by G.A. Clark and Jonathon Marks. (Lubenow)

4. That mtDNA can determine species distance and distinguish between species. - refuted by Maryellen Ruvolo and Simon Easteal. (Lubenow)

The botton line, Jose, is that all theoretical interpretations of genetic data which support Darwin's original racial theory that all human beings originated from more primitive human and non-human species in Africa, are simply modern forms of neo-Darwinist racism in biology.

[jcrawford]

This is just plain old-fashioned non-genetic neo-Darwinist theory though, Jose, and has nothing to do with the genetic data you presented earlier or any genetic data about Kangaroos and the "original population of early mammal-like critters" you imagine "got split up." Besides, we're talking about human beings and human migrations here, not Kangaroos or early-mammal like "critters."

If Jose compares human migrations to kangaroo migrations, wouldn't one expect it to be within the Darwinist milieu, which holds that man is but one of many animals, and not "specially created"? And therefore, migrates?

Everyone already knows that some human beings have migrated from one continent to another and that kangaroos haven't, so I don't see what kangaroos or early mammal-like "critters" have to do with human migration.

Shouldn't Jcrawford be asking himself if the theory is self-consistent and consistent with the data?

The only factual data consistent with neo-Darwinist theories of human evolution is that all neo-Darwinists agree that modern men and women in Eurasia, the Middle East and Africa all descended from more primitive people in Africa who originated from African monkey and ape ancestors once upon a time. All other "consistent data" from fossils and genetics is premised, interpreted and extrapolated on the basis of Darwin's original assumptions about the origin of human 'species' from anthropomorphous apes.

If we were to ask Jcrawford to explain diversity, and he were to bring up Noah's Ark, would we not be chastised if we were to say, "But that assumes the Bible is correct"?

No. You would not be chastised for saying that the Bible is correct. I would merely point out that while the Noah's Ark Model can account for diversity, it has nothing to do with the neo-Darwinist topic of human evolution.

The correct thing to do would be to allow him to explain the dynamics of the Noachian Flood, and then nail him on the fact that the story has no explanatory power...NOT try to short-circuit him at the point where Noah's Ark is mentioned.

Or perhaps I'm missing something.

Yes, perhaps you are, since those old "short-circuit" and 'bait and switch' tactics that Clarence Darrow used in the Scopes trial won't work on an Internet thread dedicated to exploring the ramifications of neo-Darwinist theories of human evolution.

[The Happy Humanist]

Everyone already knows that some human beings have migrated from one continent to another and that kangaroos haven't,

They haven't? Then how did they get to Australia from Mt. Ararat?

All other "consistent data" from fossils and genetics is premised, interpreted and extrapolated on the basis of Darwin's original assumptions about the origin of human 'species' from anthropomorphous apes.

Trilobite droppings. The only basis on which the data is interpreted is "what's the most reasonable explanation for this?" That the answer always happens to coincide with Darwin's original conclusions (not assumptions) is not the fault of the "neo-Darwinists." It's the fault of the data.

If we were to ask Jcrawford to explain diversity, and he were to bring up Noah's Ark, would we not be chastised if we were to say, "But that assumes the Bible is correct"?

No. You would not be chastised for saying that the Bible is correct. I would merely point out that while the Noah's Ark Model can account for diversity, it has nothing to do with the neo-Darwinist topic of human evolution.

This is nothing more than a transparent attempt to paint my response as irrelevant, when you know full well I was giving an example. You also know full well I did not say "What if I said the Bible is correct?" Pardon me, JCrawford, your tactics are showing.

Yes, perhaps you are, since those old "short-circuit" and 'bait and switch' tactics that Clarence Darrow used in the Scopes trial won't work on an Internet thread dedicated to exploring the ramifications of neo-Darwinist theories of human evolution.

Right you are. So why do you constantly employ them?

[Jose]

Pardon me for a bit while I grade a pile of papers. I'll get back to the discussion as soon as I can.

[jcrawford]

Everyone already knows that some human beings have migrated from one continent to another and that kangaroos haven't,

They haven't? Then how did they get to Australia from Mt. Ararat?

Since Australia wasn't a continent separated by water from the land mass of Asia back then, they probably hopped.

[The Happy Humanist]

Everyone already knows that some human beings have migrated from one continent to another and that kangaroos haven't,

They haven't? Then how did they get to Australia from Mt. Ararat?

Since Australia wasn't a continent separated by water from the land mass of Asia back then, they probably hopped.

Oh, THAT'S right. Of course. Silly me! The continent of Oceania has travelled 4000 miles in 6000 years. What was I thinking?

[bernee51]

Everyone already knows that some human beings have migrated from one continent to another and that kangaroos haven't,

They haven't? Then how did they get to Australia from Mt. Ararat?

Since Australia wasn't a continent separated by water from the land mass of Asia back then, they probably hopped.

Back when exactly?