RE: Mitochondrial DNA Study Supports Out of Africa Evolution

From: Glenn Morton (glenn.morton@btinternet.com)
Date: Sat Dec 09 2000 - 10:57:27 EST

  • Next message: David F Siemens: "Re: Ethics of human space travel"

    I had sent this only to Blaine. I made a couple of changes and am now
    sending this to the list.

    Blaine wrote:

    >"Paternal contribution of mtDNA is effectively a dead issue, and can not be
    used to
    >criticize phylogenetic studies based on the use of mtDNA."

    Unfortunately, Nature seems to have ceased sending me my journals (which
    take twice as long to get to me over here anyway.) As of this time, I must
    agree with what Blaine writes. Paternal inheritance can't be used to
    criticize mtDNA studies. However, nothing in any of this rules out
    contributions from H. erectus and Neanderthal to human nuclear genetic
    material.

    One cannot use the mtDNA results as if all mankind consisted of was mtDNA.
    There is also much nuclear DNA. As it stands now, some of the alleles have
    coalescence times of well over 500,000 years, long prior to when any
    anatomically modern humans existed. Recent studies of the MHC region shows
    that exons have a coalescence time of 7 million years---long before our
    genus existed.

    “If we apply the substitution rate of 1.4 x 10-9 per site per year, the
    average intron divergence among alleles within lineages corresponds to a
    mean age of 250,000 years. By contrast, the amount of exon-2 sequence
    divergence among alleles within lineages is much greater and corresponds to
    an average age of 7.06 Myr, using a substitution rate for MHC exon sequences
    of 0.97 x 10-9 per site per year. Thus, the intron sequences yield a more
    recent estimate for the diversification of alleles within a lineage than do
    estimates for the diversification of alleles within a lineage than do
    estimates based on exon-2 sequences.” Tomas F. Bergstrom Agnetha Josefsson,
    Henry A. Erlich & Ulf Gyllensten, “Recent Origin of HLA-DRB1 Alleles and
    Implications for Human Evolution” Nature Genetics, 18(1999):237-242, p. 239

    And even the introns show much older contributions than the 38,000 years of
    mtDNA.

    "Mitochondrial DNAs from individuals of African origin show a ragged
    distribution consistent with constant population size, whereas the
    bell-shaped distribution of the non-African comparisons clearly indicates a
    recent population expansion. The assumption of constant population size can
    be verified by tests of selective neutrality that examine the correlation
    between the mean pairwise sequence difference (MPSD) and the number of
    segregating sites (S). In the African group, we cannot reject this
    assumption (Fu and Li's D = -1.17 ; Tajima's D = -1.22 ), consistent with
    the premise that the population has been of roughly constant size . However,
    it can be rejected in the non-African group (D = -4.02 ; D = -2.28),
    indicating that this group has experienced a period of population growth.
    The time when the expansion began was estimated ( = 20.23) to be about 1,925
    generations ago. Assuming a generation time of 20 yr this equates to 38,500
    yr BP, a date that coincides with the onset of a period of cultural change
    about 35,000-40,000 years ago. This involves, for example, the first
    appearance of regional cultural variation and the acceleration of
    artefactual change."MAX INGMAN*, HENRIK KAESSMANN†, SVANTE PÄÄBO† & ULF
    GYLLENSTEN*, "Mitochondrial genome variation and the origin of modern humans
    " Nature 408(2000):708-713

    Two comments on this. First, if it is true, as the evidence suggests, that
    mtDNA is only passed via the mothers, what the data means is that the
    daughters of Eurasian Eve spread rapidly through the population. It really
    doesn't say anything about nuclear genetics. One could explain this
    young-mtDNA pattern with the old nuclear genome by assuming the following
    scenario: Suppose a woman had exceptionally beautiful or sexually attractive
    daughters. They would be highly prized. Their daughters inheriting this
    beauty or sexual attractiveness, would also be prized. Tribes could make
    peace with other tribes by marrying one of these daughters with their
    enemies. Thus the mtDNA would pass throughout the world without any nuclear
    genome restriction. Lots of anthropologists have given very speculative
    views as to why anatomically modern humans took over the world. Things such
    as the development of language, the advent of the modern mind, superior
    technology, disease that wiped out the archaic populations etc. have been
    suggested. But, those don't really explain the spread of mtDNA by females
    alone. So what else can we hypothecate?

    Well, here is a fanciful, but equally effective means of spreading mtDNA
    around the world. Look at the apes. Their female breasts are really small --
    not much larger than male breasts. Somewhere along the line, human women
    developed bigger breasts. It is a well known fact that men are highly
    interested in women's breasts. Women with such an enhanced trait would
    spread around the world rapidly if they were the only big breasted women in
    a world of humans with ape-like breasts. Thus, the spread of mtDNA could be
    due to nothing more than the development of breasts rather than of language
    or the modern human mind. Of course there is no fossil record that this
    occurred, but then there isn't a fossil record of the appearance of the
    human mind, language or any other item often suggested as being the reason
    modern humans won out. Yet those views are defended vigorously as if there
    was metaphysical truth in them. I would suggest that the appearance of
    breasts is much more likely to have spread the mtDNA around than is the
    appearance of the human mind. My feminist friends would find their
    preconceptions of men fulfilled in this theory. Men would merely be doing
    what they expect--using women as sex objects rather than appreciating the
    person. :-)

    Is this sexist? yes. Is this demonstrable? Not any more than any of the
    other speculations on why anatomically modern men won out. Is this
    consistent with the mtDNA data AND the nuclear data? YES. And the beauty of
    this fanciful view is that it puts in perspective the fallacy of equating
    mtDNA with the advent of humanity!

    One other comment must be made.

    The problems with equating the appearance of the modern man with the
    invention of the upper Paleolithic Aurignacian industry, which is what the
    above author's are doing, are many.

    First, there is NO evidence of the Aurignacian occurring outside of Europe
    prior to its appearance in Europe.
    "
    The flake-dominated Levantine Aurignacian at Kebara with some blades,
    bladelets, El Wad points, and keeled and other endscrapers dates to only
    36,000-28,000 B.P.. The Early Upper Paleolithic of the Near East has not
    produced any ornaments or bone tools, the 'bottom-line' diagnostics of the
    European early Upper Paleolithic. Either the Aurignacian is a cultural
    entity (and if so, it is younger in Israel than in Europe), or it is a
    phenomenon produced in large part by technological convergence, or it spread
    from Europe to the Near East. The last hypothesis was recently adopted by
    Gilead and Bar-Yosef, following Garrod. Thus the dating of the Aurignacian
    and other (related?) Upper Paleolithic industries in southeast Europe is
    critical to all invasionist arguments."Lawrence Guy Straus, "The Iberian
    Situation between 40,000 and 30,000 B.P. in Light of European Models of
    Migration and Convergence," in G. A. Clark and C. M. Willermet, Conceptual
    Issues in Modern Human Origins Research, (New York: Aldine De Gruyter,
    1997), pp. 235-252, p. 243

    Second, the earliest examples of the Aurignacian are to be found in
    Spain--the last refuge of the Neanderthals and one of the last places
    inhabited by modern man.

     What emerges very strikingly from the pattern of radiocarbon dates plotted
    in figure 2 is that whilst we now have a total of 20 separate radiocarbon
    measurements of between 37,000 and 41,000 B. P. for Aurignacian levels in
    the northern Spanish sites, we have not so far been able to secure a single
    radiocarbon date for an early Aurignacian level in the ‘classic’ region of
    southwestern France earlier than c. 36,000 B. P. As figure 2 reveals there
    is now a striking clustering of the earliest Aurignacian dates in this
    region between 33,000 and 36,000 B. P., with dates in this time-range from
    seven sites(Abri Pataud, La Rochette, La Ferrassie, Le Flageolet, Abri
    Castanet, Combe-Sauniere, and Roc-de-Combe). Unless all of these dates are
    heavily distorted by contamination—which seems highly unlikely on many
    different counts—the obvious implication is that the main occupation of
    southwestern France by Aurignacian groups did not occur until around
    35-36,000 B. P. in radiocarbon terms—that is around 4,000-5000 years later
    than the earliest Aurignacian in the northern Spanish sites." Paul Mellars,
    "The Neanderthal Problem Continued,” Current Anthropology,
    40(1999):3:341-364, p. 347-348

    This has been known for more than 7 years, yet no one changes their opinion.
         "The new dates for the appearance of the so called Aurignacian
    technology in northern Spain are far older than any from the rest of Western
    Europe including SW Germany. They are much older than any dates for the
    Chatelperronian of France or for the Uluzzian (the Italian stratigraphic and
    typological equivalent of the Chatelperronian). They are about the same as
    the CvC14 dates for the Szeletian and Bohu-nician (Mousterian-Upper
    Paleolithic 'hybrid' industries) of Hungary and Czechoslovakia. While the
    northern Spanish Aurignacian dates are older than several early Aurignacian
    CvC14 determinations from Eastern and Central Europe (e.g., Velika Pecina,
    Pesko and Krems), they are about the same or perhaps somewhat younger than
    other early Aurignacian dates from Samuilica (42.8+/-1.3 ka bp) and Bacho
    Kiro in Bulgaria (a single infinite date of >43 ka bp), Istallosko level 9
    in Hungary (44.3+/-1.9 and 39.7+/-0.9 ka bp) and Willendorf level 2 in Lower
    Austria (39.5 +1.55/-1.2 ka bp and 44.7+3.7/-2.5 ka bp). All these sites
    should be redated with multiple determinations to obtain the best possible
    estimates of age. Single dates published as 'finite', but that are older
    than c.30ka bp, should probably be considered as minima. At most, there
    would seem to be a difference of ca. 5 ka between the oldest Aurignacian
    dates in Central and Eastern Europe (regions between which there is no clear
    temporal cline) and those of northern Spain. Even this relatively short
    amount of time for the supposed 'spread' of Aurignacian people or ideas
    across ca. 2300 km from SE to SW Europe may prove illusory." ~ Straus,
    Lawrence G., James L. Bischoff and Eudald Carbonell, 1993. "A Review of the
    Middle to Upper Paleolithic Transition in Iberia", Prehistoire Europeenne,
    3(January, 1993):11-27, p. 14

    Third, the earliest well dated anatomically modern human skeleton in Europe
    is dated to around 26,000 years ago--12,000 years after the first appearance
    of the Aurignacian industry.

          "No Neandertal fossil has been given a reliable date more recent than
    36,000 years B. P. (St. Cesaire). A date of about 34,000 years B. P. has
    been published for a frontal bone of modern form found at the European site
    of Velika Pecina. After that, the oldest securely dated modern skeletal
    material from Europe comes from a site near the town of Pavlov in the Czech
    Republic at about 26,000 years B. P." ~ Bernard G. Campbell and James D.
    Loy, Humankind Emerging, (New York: HarperCollins, 1996), p. 463

    Velika Pecina was directly dated on the bone itself and was found to be 5000
    years old and thus this is no longer considered to be relevant:

    "The human frontal bone from Velika Pecina, generally considered one of the
    earliest representatives of modern humans in Europe, dated to ~5 ka B.P.,
    rendering it no longer pertinent to discussions of modern human origins.”
    “Fred H. Smith, Erik Trinkaus, Paul B. Pettitt, Ivor Karavanic, and Maja
    Paunovic, “Direct Radiocarbon Dates for Vindija G1 and Velika Pecina Late
    Pleistocene Hominid Remains,” Proceedings of the National Academy of
    Sciences, 96(1999):2:12281-12286, p. 12281

         "As in France and elsewhere in western Europe, there is still a real
    absence of well-dated, diagnostic, well-described human fossils
    uniquivocally associated with the Aurignacian before ca. 30,000 B.P. This
    makes it all the more ironic that, at present, the only well-dated,
    well-provenienced, well-described hominid remains to be found with both the
    Chatelperronian and the early Aurignacian are Neandertals. Whether the late
    Aurignacian (with unequivocal Cro-Magnons) and the early Aurignacian (with
    no clear-cut hominid associations) are the same 'thing' is anything but
    clear." ~ Lawrence Guy Straus, "The Iberian Situation between 40,000 and
    30,000 B.P. in Light of European Models of Migration and Convergence," in G.
    A. Clark and C. M. Willermet, Conceptual Issues in Modern Human Origins
    Research, (New York: Aldine De Gruyter, 1997), pp. 235-252, p. 245

    Neanderthals have been found with Aurignacian material at Vindija cave.

     "For example, Wolpoff et al. describe a retromolar space in the Vindija 207
    mandible associated with the early Aurignacian in Croatia, and wide
    retromolar spaces are also found in Predmosti 3,4 and 21, Brno 2, and
    Stetten 1, all dated to the early Upper Paleolithic." ~ David W. Frayer,
    "Evolution at the European Edge: Neanderthal and Upper Paleolithic
    Relationships," Prehistoire Europeenne, 2:9-69, p. 14

    A retromolar space is diagnostic of Neanderthals as modern humans don't have
    them. This is a large gap between the back tooth and the ascending part of
    the jaw.

    For the date on this Neanderthal see also
    Fred H. Smith, Erik Trinkaus, Paul B. Pettitt, Ivor Karavanic, and Maja
    Paunovic, “Direct Radiocarbon Dates for Vindija G1 and Velika Pecina Late
    Pleistocene Hominid Remains,” Proceedings of the National Academy of
    Sciences, 96(1999):2:12281-12286, p. 12284

    In spite of all this, the myth that data supports the origin of the
    Aurignacian by modern man continues to be taught.
    glenn

    see http://www.flash.net/~mortongr/dmd.htm
    for lots of creation/evolution information
    anthropology/geology/paleontology/theology\
    personal stories of struggle



    This archive was generated by hypermail 2b29 : Sat Dec 09 2000 - 10:55:31 EST