PART 7 OF 10
Response on the issues to:
"Science or science?" and "Darwin on Trial"
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SYNOPSIS
Parts 7-10 of this series are a response on the issues to David Wolfe's/
Nature's First Law's recent "Science or science?" posting against evolution
that was based on creationist Phillip Johnson's book "Darwin On Trial."
This is a lengthy series--however, to thorough refute creationists claims
requires going into the facts in at least some amount of detail, something
creationists themselves often do not bother to do. I go into them here to
show how clearly creationism fails the tests of the evidence. (If, however,
you want the "short" or "lite" version which states the facts simply
without going into so much supporting evidence, Part 6 of this series is a
much-condensed summary version of Parts 7-10 you can read instead to get
the general idea.)
The root of the conflict here between evolution/creationism--and the
relevance to dietary questions--is that the extensive scientific evidence
from evolution and paleontology directly refutes the idea that pure
vegetarianism is humanity's "natural" diet, since it shows that humans are
and always have been omnivores. While there may of course be other reasons
for eating a vegetarian diet, continuing to promote it on the basis that it
is humanity's "original" "natural" diet, when one is aware of what science
and evolution have shown about the human past, is to do so under false
pretenses. (Evolution does, however, support a raw or predominantly raw
diet.) Wanting to promote vegetarianIsm and/or fruitarianism as "natural,"
therefore, leaves no option but to attack evolution directly, as "Science
or science?" does.
Also given here are many pointers to on-line sources where one can read
further about evolution vs. creationism and access the scientific
references in support of the refutations of creationism given here.
Additionally, the possibility of maintaining belief in God (or "supreme
being, "ground of being," etc.) while also accepting evolution is
addressed, as a concluding consideration for those who have trouble with
evolution for that reason.
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BRIEF TABLE OF CONTENTS
A. The bulk of this posting looks at the creationist assertions along with
their refutations based on the evidence, in 7 sections:
1. The supposed lack of transitional forms in the fossil record (there are
actually many).
2. Whether microevolution (gradualistic mechanisms) can explain macroevolution
(evolutionary leaps in form or function that occur rapidly).
3. Whether embryology (development of embryos prior to birth) should retrace
evolutionary development as seen in the fossil record.
4. The role of the new molecular genetic findings as an independent line of
evidence for common ancestry.
5. Is evolution "just a theory"?
6. Are evolutionary explanations "true by definition" (tautological) in such a
way that they can't be fairly tested?
7. The "philosophical" question: Are the "rules of science" rigged against any
other explanation than evolution?
8. A final section looks at how it can be possible to believe in God while
still accepting evolutionary science, for those to whom this is a
concern.
B. A wrapup gives pointers to and summarizes particularly interesting or
relevant websites, including: an on-line debate between Phillip Johnson and
an evolutionary biologist; critical reviews of "Darwin on Trial" as well as
Michael Denton's "Evolution: A Theory In Crisis" (another source Wolfe/NFL
cited) for "Science or science?"; links that look in-depth at "creationist
whoppers" and debating tactics; plus links containing good crash-courses
that outline the basics of evolutionary theory for those interested.
NOTE ON SOURCE MATERIAL
Much of the information discussed and the pointers given here come from the
encyclopedic "TalkOrigins" website at http://www.talkorigins.org. This is
for several reasons. First, since everyone here on the Raw-Food listgroup
is online (obviously :-) ), and most probably have access to a web browser,
this should make it easy--if you have any interest of course (which I grant
is probably debatable :-) )--to check out all the links given here to SEE
FOR YOURSELF just how much evidence there is for evolution and how badly
creationists have ignored or distorted it.
If I could make one plea here, it would be that if you have an interest in
the subject, you do not simply take my word for any of the summaries I'll
give here, nor the word of David Wolfe/NFL in any rebuttal he/they may post
to this. Again, if you have an interest, do the ol' point-and-click thing,
and read about the evidence for yourself. Numerous links on the site
document in considerable detail how the record of creationists as a whole
is governed by the persistent tactical use of distortion, deception, and
dishonesty, often considerably exacerbated by ignorance of the subject
matter and refusal to face facts.
Second, the www.talkorigins.org site is one of the best and most complete
reference sources available anywhere on the evolution/creationism
controversy, from what I can tell. Given that I did not have a lot of time
to spend on researching and tracking down scientific references for what
ought to be a dead-dodo issue among anybody even halfway knowledgeable on
the science in the first place, it's the type of resource where you can
quickly find scientific material tied to peer-reviewed references on just
about any topic of interest relating to the controversy that you could
possibily hope to find. The Talk.Origins site is completely indexed and
overwhelmingly replete to the point of overflowing with references to the
huge array of scientific source literature in meticulously documenting its
rebuttals to creationist claims and distortions--references you can easily
use to track down the primary peer-reviewed source literature yourself if
you want.
Also, the Talk.Origins site is the result of the collective effort and work
of numerous individuals--many of them working research scientists--who have
been through the debating mill and flame wars over evolution/creationism on
the alt.talk.origins Usenet newsgroup for years now. Much of the
information and rebuttals given at the site are a result of
cross-examination in the flame-war trenches. If there is anything relating
to the evolution/creation controvery that has been argued or hypothesized
anywhere, you can bet the regulars on the talk.origins newsgroup who
contributed to the www.talkorigins.org website will have seen it many times
before. The essays, FAQs, and other pieces (even including some by
creationists) to be found on the site--or linked to it--have come from many
rounds of debate on these issues.
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THE CREATIONIST ASSERTIONS
Johnson's book "Darwin on Trial" makes several assertions about evolution
that boil down to the following claims (all of which have been heard
before, though Johnson's emphasis in the final point below is perhaps
somewhat different):
1. There are no transitional forms between species in the fossil record as
evolution predicts there should be. Or at least so few or so shakily
supported by evidence as to be virtually none, and therefore meaningless
against the overall backdrop of gaps between the "sudden" appearance of
whole and complete new species seen in the fossil record.
2. Micromutation (exemplified by the mechanisms of random mutation and
natural selection) may exist, but it does not (and cannot in principle)
explain the macromutational leaps required to create wholly different
species or new types of organisms and structures. Therefore some "miracle
factor" or unknowable "mystery factor" is required.
3. The idea that "ontogeny recapitulates phylogeny" (that embryological
development of an organism before birth should retrace its species'
evolutionary development) has been shown to be in error; therefore
evolution is in error.
4. Modern molecular genetics is nothing new in terms of what it actually
allows us to determine with respect to the ancestry of fossils. It is just
a newer methodology for classifying organisms by certain physical features
(in this case genetic features). Therefore, measuring genetic distance
between creatures cannot be used to impute ancestry any more than fossil
forms can.
5. Evolution is not a fact, it is merely a theory.
6. Evolution contains certain axioms or tenets such as "survival of the
fittest" which are framed as "tautologies"--statements that are true by
definition in a way that makes them either meaningless or untestable/
unfalsifiable.
7. Lastly, the "rules of science" are philosophically biased by
"materialistic naturalism" and rigged at the outset against any other
explanation than evolution.
It should be mentioned so we don't create a "straw man" of Johnson that he
takes pains at the outset of the book to distinguish himself from the
young-earth creationists who believe in a literal Genesis account of
creation. Johnson takes the geological evidence for age of the earth and
the existence of prehistoric fossils to be true. He just doesn't believe
evolution explains how they got there, or is at least at best a partial
explanation, with unspecified, mysterious, miraculuous forces constituting
the actual "driving force" behind major evolutionary changes.
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SECTION #1
THE SUPPOSED LACK OF TRANSITIONAL FORMS IN THE FOSSIL RECORD
This is perhaps the biggest humdinger of all in "Darwin on Trial" (as it is
throughout all of creationist literature) as well as in "Science or
science?". Johnson, though, makes it easy to swallow his smooth
presentation with a dose of myopia which only manages to ignore--gee, I
dunno--at least a measly one or two hundred or so examples of transitional
fossils, such as those meticulously documented at the Talk.Origins website,
at least. :-) With his well-practiced lawyerly tactics, Johnson ignores
score upon score of examples of known transitional fossil forms (most which
he apparently isn't even aware of), while single-handledly managing to
belittle, gloss over lightly, misrepresent, or damn with faint praise the
mere handful of transitional fossils he _does_ manage to address.
That shouldn't be surprising, however, because Johnson didn't bother to
consult or list more than a similar mere handful of reference sources
linked to primary peer-reviewed scientific source material in his "Research
Notes," basing his book as he did mostly on popularized sources. I mean,
gee, to consult the peer-reviewed literature--or sources (such as the
TalkOrigins website we have today) that themselves depend on direct
citations of it--might bring up too many discomfiting details he'd have to
consider. We can't do that, now, can we? Good heavens, it might make
people's eyes glaze over from having to consider a few of those godawfully
boring _details_ that keep us _honest_. (One is reminded here of the saying
upstanding theists ought to be expected to bear in mind, that "God is in
the details." :-) )
For the most definitive and throughgoing summary of the known "transitional
forms" in the fossil record available at www.talkorigins.org, click on the
link http://www.talkorigins.org/faqs/faq-transitional.html, titled
"Transitional Vertebrate Fossils FAQ," by Kathleen Hunt
<[log in to unmask]>. This is another link that is, again, replete
with references to the scientific literature (approximately 80-90 refs in
all). This particular FAQ is comprehensive enough in its depth and listing
of transitional forms that the compilation quite easily and literally
amounts to easily a hundred, and perhaps--without having done an exact
count--even as many as two hundred or more. And it is a partial list at
that. Kathleen mentions in her author's note to the FAQ that the original
researching and compiling of it took three years (from 1991-1994), which
was only possible as an extracurricular hobby-project due to a fully-paid
fellowship as a new grad student in this field with lots of time on her
hands.
If you have any lingering doubts planted by creationists or their
supporters or hangers-on that there simply aren't any transitional fossil
forms to be found, this compilation should easily crush such
misconceptions. There is example after example after example here, in
chronological order, that explode the creationist claims into the tiniest
of pieces. (We'll be listing some of these shortly.)
Important to note here is that there are fossil transitions of both major
types possible, that is: (1) general transitions linking "chain of genera,"
as Hunt puts it, i.e., the ones linking widely disparate fossil forms and
that would be considered more "macroevolutionary" in nature showing a
progression through large differences in form; as well as (2) the most
direct and finest-grained type possible, that is, direct species-to-species
transitions. And not only species-to-species transitions of the
"microevolutionary" type that creationists admit only as meaningless
micro-exceptions, but full-blown sequences of species transitions that,
cumulatively, cross over complete genus and family lines. As Hunt quotes
Stephen Jay Gould at the above link in observing: "The supposed lack of
intermediary forms in the fossil record remains the fundamental canard of
current antievolutionists." [Canard = "an unfounded or false, deliberately
misleading story," sez the Am. Heritage dictionary]
There are also some good examples here of a few former "gaps" in the record
that with further research and discovery have yielded transitional fossils
after all. One of these is a recent dinosaur find in Montana that found
circumstantial evidence fitting the theoretical picture for "punctuated
equilibrium" as the mechanism by which several new dinosaur species arose
in the relatively short geological timespan of just 500,000
years--following 5 million years of stasis--after they had become
geographically isolated during an abrupt rise in sea level at the time.
(See http://www.talkorigins.org/faqs/faq-transitional/part1b.html for a
brief discussion.)
On this issue, Hunt notes that evolutionary examples of both "gradual
evolution" and "punctuated equilibrium" are found in the fossil record--the
current debate being not over which is the correct model of evolutionary
change (in fact, both occur, rather than either/or), but how much of each
occurs, why, and in what kinds of situations.
Hunt also notes--and I would interject, just as one would expect--that the
gaps in the fossil record become fewer and fewer as one approaches the
present day, since many more fossils in the more recent geological strata
closer to the surface are likely to be (and have been) recovered. In this
connection, Hunt mentions that in the fossil record of species-to-species
transitional forms (the tightest linkages in transitional sequences
possible), there are at least 25 mammal species from the latest geological
period (the Pleistocene, from 2.5 million to 10,000 years ago) that can be
tied to their ancestor species by observable transitions in the fossil
record.
EXAMPLES OF TRANSITION FOSSILS
Here, then, is a condensed and summarized list of some of the known
transitional fossils discussed on the site:
(An important note: What infrequent "gaps" there may be listed below in the
fossil sequences are gaps in _time_--that is, gaps due merely to a lack of
sufficient fossils to analyze in the first place from a certain time
period--not gaps in the sense of "jumps" from one type of fossil form to
another that occur closely together in chronological sequence. This is an
important distinction, because what creationists mean by a "gap" is an
actual "jump" in form from one fossil to the next when there is little to
no intervening time period in between.)
THE TRANSITION FROM PRIMITIVE JAWLESS FISH TO SHARKS, SKATES, AND
RAYS: A
gap near the beginning of the transition (due to the earliest fossils in
the lineage being so fragmentary that not much can be reconstructed about
them). After that, 6 transitional forms show up in the record. The
transitional forms are: Cladoselache, Tristychius, Ctenacanthus,
Paleospinax, Spathobatis, and, Protospinax. (Cladoselache is considered
probably not in the direct line of ancestry, but indicative of typical
features.)
FROM PRIMITIVE JAWLESS FISH TO BONY FISH: 6 transitional forms after an
initial gap (again, the gap is due to such fragmentary fossil traces, they
can't be reliably identified). The transitional forms are: Acanthodians,
Palaeoniscoids, Canobius/ Aeduella (later paleoniscoids), Parasemionotus,
Oreochima, and Leptolepis.
FROM PRIMITIVE BONY FISH TO AMPHIBIANS: 7 transitional forms with but one
gap in the sequence: Paleoniscoids (these branched in two directions,
including to the line of forms mentioned just above), Osteolepis,
Eusthenopteron/ Sterropterygion, Panderichthys and Elpistostege,
Obruchevichthys, gap, Hynerpeton/ Acanthostega/ Ichthyostega,
Labyrinthodonts.
TRANSITIONS WITHIN THE AMPHIBIAN LINEAGE: 10 transitional forms are listed
in the sequence: Temnospondyls, Dendrerpeton, Archegosaurus, Eryops,
Trematops, Amphibamus, Doleserpeton/ Schoenfelderpeton, Triadobatrachus,
Vieraella, Karaurus.
FROM AMPHIBIANS TO FIRST REPTILES: 4 transitional forms: Proterogyrinus,
Limnoscelis/ Tseajaia, Solenodonsaurus, Hylonomus/ Paleothyris.
At this point, I'll dispense with listing of genus names for the sake of
brevity, now that the point has been made above that paleontologists can
identify transitional forms with considerable precision.
TRANSITIONS AMONG REPTILES: There are so many examples to choose from here
that Hunt lists just two of the phylogenies (overall sequences of forms).
FROM SYNAPSID REPTILES TO MAMMALS: Among the best-documented of all
transitional sequences, the list here comprises 30 transitional forms,
beginning with 16, then a gap due to the existence of only one known fossil
recovery in this line from the late Triassic period, then 14 more
successive transitional forms.
FROM DIAPSID REPTILES TO BIRDS: This transitional line is most famous for
the Archaeopteryx reptilian-bird transitional fossil found in 1861, though
the overall lineage here is still "gappy" according to Hunt. Nevertheless,
there are now 2 or 3 candidates for ancestral forms even more primitive
than Archaeopteryx, and 4 transitionals can be seen after Archaeopteryx.
TRANSITIONS AMONG MAMMALS: Where transitional forms among the mammals are
concerned, there are scores of examples too numerous to go into in a post
like this. However, one good example is worth mentioning here for how it
demonstrates what can turn out to be the arbitrary nature of "gaps" in the
fossil record. The two orders (a) "lagomorphs," which includes rabbits,
hares, and pikas; and (b) "rodents" (mouse, rat, squirrel, beaver) are two
very similar-looking modern orders that were long thought to have been
unrelated because they appeared separately, suddenly, and fully formed in
the fossil record of the late Paleocene. But--as it was to turn out--that
proved to be just an artifact of the fossil record: Recent discoveries in
newly tapped deposits in Asia (all the earlier discoveries were from North
America and Europe where most finds have come from) have unearthed new
fossils now thought to be the probable common ancestor (transitional form)
that led to the two modern orders, showing they didn't appear suddenly or
separately after all.
And there are so many more examples of transitional sequences in the fossil
record that I won't bore any of us further with them here. But the
foregoing should give a good enough idea of how dismal the record of
Phillip Johnson and David Wolfe/NFL is in seeking out the evidence. In the
next section on micro vs. macroevolution, I'll give a few more examples of
fossil transition sequences at the species-to-species level that
demonstrate microevolutionary changes can indeed lead to macroevolutionary
change. But for more examples than that, and there are an incredible number
more, if you are a real glutton for punishment just click on the
"Transitional Vertebrate Fossils FAQ" link yourself at
http://www.talkorigins.org/faqs/faq-transitional.html and follow through
from beginning to end--it's been work enough just summarizing what I have
here. :-\ :-) Without doing an actual count, one would have to estimate
that Hunt's listing easily goes into the 100-200 range detailed
enumerations of transitional forms--and the characteristics that make them
so--and it is, at that, only a partial listing. Again: See for yourself,
and note the meticulous attention to detail in terms of Hunt's referencing
of the evidence to the primary scientific literature.
WHAT ABOUT THE REMAINING GAPS IN THE FOSSIL RECORD?
In addition to the numerous transitional fossil forms listed and discussed
here, Hunt also discusses the gaps in the fossil record, the differences
between transitions that document sequences between general lineages as
opposed to those documenting individual, species-to-species transitions;
why the gaps are there; what they *really* signify (not what the
creationists infer), and so on. One of the most telling pieces of
information Kathleen touches on that the creationists almost never seem to
mention is just how frequent the sampling rate in the fossil record has to
be before you can eliminate all the gaps:
To demonstrate _anything_ about how a species arose, whether it arose
gradually or suddenly, you need exceptionally complete strata, with
many dead animals buried under constant, rapid sedimentation. This is
rare for terrestrial animals. Even the famous Clark's Fork (Wyoming)
site, known for its fine Eocene mammal transitions, only has about one
fossil per lineage about every 27,000 years. Luckily, this is enough
to record most episodes of evolutionary change (provided that they
occurred at Clark's Fork Basin and not somewhere else), though it
misses the rapidest evolutionary bursts. [NOTE: One estimate given by
Niles Eldgredge co-creator with Stephen Jay Gould of the "punctuated
equilibrium" theory--on pp.99-100 of his 1995 book "Reinventing
Darwin" (John Wiley & Sons: N.Y.) is that evidence from the fossil
record suggests a timespan of anywhere from "5,000 to 50,000 years"
to be all that is necessary for rapid macroevolutionary speciation
events, and some molecular geneticists think even that estimate may
be "overly generous." --Ward]
In general, in order to document transitions between species, you
need specimens separated by only tens of thousands of years (e.g.
every 20,000-80,000 years). If you have only one specimen for
hundreds of thousands of years (e.g. every 500,000 years), you
can usually determine the order of species, but not the
transitions between species. If you have a specimen every
million years, you can get the order of genera, but not which
species were involved. And so on. These are rough estimates
(from Gingerich, 1976, 1980) but should give an idea of the
completeness required.
Note that fossils separated by more than about a hundred thousand
years cannot show anything about how a species arose. Think about it:
there could have been a smooth transition, or the species could have
appeared suddenly, but either way, if there aren't enough
fossils, we can't tell which way it happened.
There is much misunderstanding about these issues on the part of
creationists about just what constitutes a "gap" in the fossil record, and
just how "sudden" macroevolutionary events responsible for them actually
are or not. Creationists also have an irascible tendency to skate away from
the evidence by taking the impossible-to-reason-with position that no
matter how close the resemblance is between two successive forms in the
fossil record, it's still a "gap."
Although in whatever number of instances evolutionary changes may be rapid,
they are certainly not _instantaneous_ in the way the creationists' use of
the term "sudden" tends to imply. Where uninterrupted and complete
time-slices of fossil sequences have been found in fine-grained enough
resolution as Hunt outlines above, you do not see "sudden," or at least
_absolutely_ "sudden," "jumps" or "gaps" in fossil forms. Instead you see
_very_rapid_ changes that are, however, graduated enough to be able to see
the transitions between forms.
It also needs to be pointed out that "gaps" or instances of so-called
"sudden" macroevolution are "seen" far more often in older geological
strata where the numbers of fossils recovered are spotty to begin with. The
closer one gets to the present with more and more complete time-slices of
fossils available for examination, the fewer "sudden" macroevolutionary
events one sees--again, one sees rapid gradations instead. (See Kathleen's
link at http://www.talkorigins.org/faqs/faq-transitional/part2a.html near
the top of the page for a chart titled "Timescale" to illustrate the
varying quality of the fossil record over more recent evolutionary time.)
Hunt also has a nice, albeit brief, discussion of why certain geological
time periods--due to the geological history of the earth--leave behind
fewer fossil remains than others.)
END PART 7
--Ward Nicholson <[log in to unmask]>
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