RE: New genetic data and mankind's ancestry

From: pruest@pop.dplanet.ch
Date: Sat Mar 10 2001 - 11:12:57 EST

  • Next message: John W Burgeson: "Earth View"

    Hi Glenn, you wrote (I quote your comments as << ... >>):
    << In that outline we have much agreement. I would probably disagree
    strongly
    with the late date you would advocate for the origin of soulish humans.
    >>

    The date estimate I gave for the origin of soulish humans is ~2 million
    years ago, as I wrote: "In this evolutionary descent are included the
    bodily, as well as the psychological or soulish aspects (cf. the
    expression 'living souls' used in Genesis 1:20 for animals)", implying
    that for this time "H", we have only the paleoanthropological data,
    presumably the start of the biological genus Homo.

    << First, the 'newest' data that I cited argues against a bottleneck.
    The idea
    of a bottleneck in the past 100,000 years is a rather controversial
    point
    and is entirely unsettled. Some geneticists believe that mtDNA and the
    Human alu insertion show a recent bottleneck, but other data (the
    nuclear
    genetics) don't argue for this.
    The Oct. 10 PNAS article I have cited before says:
    "... Here, we report worldwide variation data from a 10-kilobase
    noncoding autosomal region... indicates no severe bottleneck during the
    evolution of modern non-Africans; however, the possibility of a mild
    bottleneck cannot be excluded."
    This data shows no severe bottleneck within the time frame over which
    the
    genetic system is measuring things. >>

    My reference to the 'newest genetic data' was to Rogers A.R. "Order
    emerging from chaos in human evolutionary genetics (commentary)",
    Proceedings of the National Academy of Sciences USA 98 (2001), 779-780.
    You quoted this paper yourself [<glenn.morton@btinternet.com> Sun, 18
    Feb 2001 16:41:29 -0000, ASA list V1#2002]. It is more recent than Zhao
    Z., et al., PNAS 97 (Oct.10, 2000), 11354, which you quote above.
    Furthermore, Zhao analyzes just one stretch of DNA, whereas Rogers's
    comment reviews all the relevant literature (including Zhao). His
    conclusion appears to be reliable.

    << One other comment on the timing of S. You must be defining S based
    upon appearance alone. THere is no behavioral difference between the
    early anatomically modern humans (who appeared around 100 kyr) and the
    Neanderthals...>>

    I defined "S" purely theologically. As for it's possible dating, I
    suggested 100,000 years ago (mainly on the basis of cultural finds), but
    with a very large margin of uncertainty. Of course, since A.Held and I
    submitted our PSCF paper (published Dec.1999) suggesting this, many
    newer discoveries have been made. I don't insist on this time. But
    remember, if the human "soul" has an evolutionary history before time
    "S" (creation of the "spirit"), we might expect some evidence of culture
    before that time. I think it's rather difficult to reliably interpret
    the spiritual implications of cultural findings.

    << I would also point you to John Hawks et al, "Population Bottlenecks
    and Pleistocene Human Evolution," Mol Biol. Evol. 17(2000):1:2-22, for
    very recent arguments against such a bottleneck. First, the authors
    point out that as we go from 2 million years ago to the present, there
    is a constant increase in the number of archeological sites as well as
    evidence of increased populations living at those sites. The
    archeological record doesn't show this restricted bottleneck
    scenario...>>

    Hawks et al.'s paper was accepted Sept.15, 1999. Thus, it doesn't
    reflect all of the most recent genetic data, either. In any case, they
    indicate a population size of 10^4 to 10^5 during early human evolution
    and discuss bottlenecks of 1000, much less than the 10^4 now being
    considered for a recent bottleneck (e.g. by Rogers).

    << One other argument against using the mtDNA to infer a past bottleneck
    is
    that drosophila flies also have a very low mtDNA diversity, yet they
    have
    not had a population botteneck in a long, long time... >>

    mtDNA is just one of the systems considered, its different mode of
    evolution, and not just a low diversity, being taken into consideration.
    And it's not straightforward to conclude from a lack of a Drosophila
    bottleneck to humans.

    << Now as to the points at which man became Man, we can only look at the
    archeological remains. >>

    It depends whether you are talking about time "H" (which you are doing)
    or "S".

    << ... 1.6 MYR Man-made representational art Olduvai Gorge Homo
    erectus?
       ... 1.7 MYR Human compassion East Africa Homo
    erectus
    The art, the compassion, the beginnings of the domestication of the
    canids,
    the control of fire, the crossing of the ocean all speak of a person not
    too
    dissimilar to us. We simply can't wish this data away and allow our
    theology
    to determine what facts are acceptable and which are not. >>

    I don't propose theology to determine which facts are acceptable. But
    the interpretation of the facts, and especially the determination of
    their theological implications, is not easy. Maybe you are right, after
    all, in placing "S" at ~2 Myr ago or earlier, but I doubt it.

    << Agreed, but how big is your founding population size? 10,000 Adams
    and Eves?
    Doesn't that stretch the Scripture just a wee bit? Is the Bible really
    referring to a menage-a-decamille? >>

    When I talk of population sizes of even 10,000 for points "S" or "A", I
    am never implying more than one Adam and Eve, and these belong to point
    "A" only, much later than "S". I imply theologically genuine humans
    starting with "S", and a theologically genuine human population at the
    time of Adam and Eve, "A". Both populations would be so-called
    "pre-Adamites". (By the way, I wrote that a one-couple bottleneck could
    accommodate at most two different allelic gene lineages. It should have
    been four, two in each person, for autosomes.) As for inherited
    "original sin", I indicated that this has nothing to do with genetics.
    It is existential theology. Each human being is a sinner because each
    one has sinned (before and after Adam), not because of some inherited
    gene(s).

    << ... What we see in the modern population are several genetic systems
    that take us back much further than the 100,000 years or so that you
    want. While I agree that there are possibilities that can explain that,
    those possibilities, can't possibly explain the archeological record
    which shows a continued population explansion from 2 million years ago
    to the present. There simply isn't a time when archeological sites
    dissappear for several thousand generations! And if you try to say that
    these sites were due to non-humans, then you must explain why these
    non-humans were behaving in a very human-like fashion. >>

    I was talking about the distinction between the multiregional model and
    the recent-out-of-Africa one. The multiregional model now seems to be
    more or less ruled out: Takahata N., Lee S.H., Satta Y., "Testing
    multiregionality of modern human origins", Molecular Biology and
    Evolution 18 (2001), 172-183 concluded (on the basis of DNA sequence
    data from 10 X-chromosomal regions, 5 autosomal regions, 1 Y-chromosomal
    region, and mtDNA) that the multiregionality theory is probably wrong.
    For the scientific and theological interpretations of archeological
    finds see above.

    << As one begins to have more than one or two of these types of
    lineages, the
    odds that each of those alleles were preserved in the original pair
    becomes
    less and less likely. >>

    Adam and Eve were not "the original pair", nor were they the entire
    population of some bottleneck. And what anciently coalescing gene
    lineages passed through them has neither scientific nor theological
    relevance. Such genetic lines are at most telling us something about the
    population dynamics of the pre-Adamites, but not about Adam and Eve.

    << Unless you believe in a large amount of transspeciation event gene
    flow, genes do tell us about population ages. Only if there is a huge
    interbreeding population which speciates, can the older genes traverse
    the population bottleneck. And to claim that 10,000 breeding couples is
    Adam and Eve is certainly something I never have seen in any
    commentators book. >>

    I don't claim the human species originated with Adam, see above. Adam
    and Eve were not the first human couple. They were an individual couple
    in a historical personal relationship with God, illustrating the
    fundamental reality of the human fall. To quote A. Held and P. Ruest,
    PSCF 51 (Dec.1999), 231: "Thus, we postulate that Adam was not the first
    genuine human, but that he belonged to the human species already 100,000
    years old. In spiritual terms, he was the typical representative of the
    old (fallen) human species, both before and after his time, just as
    Christ is the risen 'firstfruits' of the new humanity of those 'born of
    the Spirit', both before and after his time on earth", with Footnote 75:
    "Romans 5:12-21. In this context, physical descent is irrelevant, for
    the old humanity (not necessarily for old Israel), just as it is for the
    new. Adam's being called 'the first man' does not refer to biological
    genealogy, as can be seen in Christ's being 'the second man' and the
    'last Adam' (1 Corinthians 15:45-47). John 3:8." Then we speculated
    about the particular task which was the object of God's special call of
    Adam: "What distinguishes Adam from earlier humans? We believe he was
    called to deal with the problem of evil, death and corruption in
    creation, to open for humanity the way into spiritual communion with
    God. Adam is called 'the first man', Jesus 'the second man' (both not in
    a biological sense!); only Adam (before the fall) and Jesus had the
    undisturbed communion with God intended for humans. The biblical
    genealogies cover the time from 'the beginning' to Jesus Christ, the
    'last Adam', who became a 'life-giving Spirit', originating a new,
    spiritual humanity."

    << None of your terms are objective for the traits you want them to
    measure. One can't measure Gen 1:28 human-ness on a scale of 1 to 10.
    One can't measure Adamness in a scale using Adamic units. Thus, you have
    defined a very very fuzzy set of definitions with which anyone can see
    what they want to see rather than what data requires. ONly if you define
    S as being anatomically modern do you even have a prayer of scientific
    objectivity. But then some anthropologists have pointed out that there
    is NO definition of anatomically modernness in all of anthropological
    literature! >>

    Time "H", the origin of the genus Homo, can be scientifically defined -
    more or less. But times "S", the origin of the spiritual dimension in
    humans, and "A", Adam and Eve, cannot be defined scientifically - in
    principle. They are given by the Bible and must be theologically
    interpreted. We may try to harmonize the biological history and the
    biblical history, and I think this makes sense. I think it is possible
    to show that the two histories are not in conflict, but we cannot use
    such a harmonization to scientifically prove that the Bible is correct -
    I get the impression that this is what you want to do.

    << The menage-a-many is not a workable Biblical viewpoint. If that is
    what
    happened, then pure and simply, the bible is wrong. >>

    The "menage-a-many" is your straw man, not my idea, see above. When I
    wrote "Old separate gene lineages can happily coexist in an undivided
    population evolving through a speciation process happening later", I was
    implying that old separate gene lineages cannot be used directly to date
    a speciation event, especially if other gene lineages coalesce at other
    times. Even if, in the extreme, you want to believe that Adam and Eve
    were the first human couple, but biologically evolved through a 2-person
    bottleneck, there still may be allelic gene lines coalescing much
    earlier (although you then would expect most gene lines to coalesce at
    time "A"). Your conclusion that "the bible is wrong" doesn't follow.

    << The population expansion after the last glaciation is due to the
    beginnings
    of farming whose antecedents go back to just after the last glaciation.
    >>

    Yes, this is a major reason usually associated with it. It may not be
    the only one. And what caused those people to begin farming?

    << Flies are quite procreative and they have none of these skills. To
    claim
    that a population increase indicates a divine command means that flies
    are
    truly the favored of God... >>

    Yes, flies, among other creatures, were blessed by God and told to
    multiply (Genesis 1:22). And so were humans (v.28). But to say that any
    population increase indicates a divine command reverses the logic
    illicitly. That, in the case of humans, the population expansion
    commanded in Gen.1:28 was presumably linked to human-specific faculties
    is based mainly on theological reasoning and has nothing to do with
    flies.

    << Are you aware that there is a whole school of anthropologists that
    believe that H. sapiens refers to all hominids from 2 million years to
    the present?... Milford Wolpoff... writes: "No speciation events seem to
    separate us from our immediate ancestors,... our lineage at the origin
    of Homo sapiens some 2 million years ago..." ... Richard Leakey wrote:
    "... all of the material currently referred to as homo erectus should in
    fact be placed within the species sapiens ... back to a little over two
    million years." ... >>

    There are splitters and lumpers. The biospecies status of fossils cannot
    be ascertained, much less their theologically defined species status.

    << But this becomes very unlikely if there are lots of nuclear genes
    which
    predate the bottleneck. And what is interesting is that we are just now
    beginning to investigate the nuclear DNA and already have several
    ancient
    lineages. >>

    Ancient gene lineages don't automatically tell us anything about the
    history of the human species. As I discussed in an earlier post [Thu, 02
    Nov 2000 20:30:12 +0100, ASA list V1#1859], a claim that HLA
    polymorphism predates the separation of human and chimpanzee, 4-7.4 Myr
    ago, was dismissed as irrelevant by T.F. Bergstrom, A. Josephson, H.A.
    Erlich & U. Gyllensten, "Recent origin of HLA-DRB1 alleles and
    implications for human evolution", Nature Genetics 18 (1998), 237.
    Allele coalescences have to be judged individually and in context.

    << Reference please. >>

    Takahata N., Lee S.H., Satta Y., "Testing multiregionality of modern
    human origins", Molecular Biology and Evolution 18 (2001), 172-183 used
    all reasonably usable data to reach their conclusion against the
    multiregionality model.

    << Present data is already reversing it. How many ancient genetic
    lineages are
    required to rule out your view? Can you even place a number on that? If
    you
    can't, you haven't given your viewpoint the scrutiny it should have. >>

    I don't think anyone can. It's a matter of relative weight of evidence.
    I'm not sold on the view, but was just quoting an interesting most
    recent review.

    Peter



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