[Coral-List] Darwin was WRONG about reef formation

Douglas Fenner douglasfennertassi at gmail.com
Sun Oct 18 06:22:11 UTC 2020

     I've just been told by a source that surely knows, that the Annual
Reviews are NOT peer reviewed!!!!  I am astonished, how can this be???:  So
beware.  I'd suggest that needs to be changed.
     One comment I received said most reefs aren't atolls.  I don't know
what the count is, but Wikipedia says there are about 440 atolls.  No
theory covers everything in the universe.  That is true with Darwin's
theory of reef formation.  His theory applies to reefs on oceanic
volcanoes, and it doesn't include the theory about sea level changes, which
describes very real aspects of coral reef formation which Darwin didn't
cover.  In addition, the world's three largest barrier reefs, the Great
Barrier Reef, the barrier reef of New Caledonia, and the Belize Barrier
reef, are all on continental shelves and Darwin's theory does not apply,
they did not form because the continents were sinking (New Caledonia is a
small fragment of continent).  Further, the Caribbean has four atolls east
of Belize and Mexico, three in Belize and one in Mexico (Chinchorro Banks)
which are on raised continental blocks not volcanoes, and thus the theory
doesn't apply to them (Cozumel may become an atoll if sea level rises
enough, it is similarly on a continental block).  I read in Wikipedia that
Nicaragua has eight atolls in the Caribbean, my guess is they are similar.
And then there are a wide variety of reef shapes that don't fit into any of
the three shapes Darwin had in his theory.  Patch reefs, faroes, bank
reefs, etc etc.  Atolls aren't always complete rings, there are crescents
and a variety of other shapes.
      As an interesting side bar, there is a book entitled "Reef madness,
Charles Darwin, Alexander Agassiz, and the meaning of coral" by David
Dobbs, 2005, Pantheon Books.  Recounts the story of how Louis Agassiz,
famous biologist at the time, argued that Darwin's theory of natural
selection was wrong, and of course lost.  His son, Alexander Agassiz, tried
to avenge his father by proving that Darwin's theory of reef formation was
wrong.  He was no more successful than his father.
      Even given all that, Darwin's theory would not predict that all reefs
would be atolls, unless volcanoes had ceased forming in the oceans and
there were no reefs on continental shelves, neither of which are the case.
He'd predict reefs in a wide variety of stages from fringing to barrier to
atolls on oceanic volcanoes, depending on their age.  Which is pretty much
what we have.  By the way, not only do volcanoes in the ocean subside, but
a large part of the loss of material above the water line is due to
erosion, not subsidence.  I live on such a volcano, Tutuila in American
Samoa, and erosion is VERY active here in the relatively high rainfall.
HUGE volumes of material have been eroded from Tutuila (which is tiny
compared to the main islands in Hawaii), I estimate cubic MILES of basalt,
much of which was weathered into clays and then eroded into the sea.  In
spite of vast amounts of erosion into the sea, the sediment didn't kill the
reefs, they are alive today.  Because it has been going on for about a
million and a half years, it is slow enough that at any one time the amount
of sediment is something the reefs can survive.  By and large the reefs
look clean today.  It is amazing what you can accomplish if you have enough
      Darwin didn't know why volcanoes subsided.  There are two processes.
One is that the growth of a volcano in the ocean puts that weight on the
plate on which it stands, which in turn floats on the very viscous
semi-fluid of hot rocks below the plate, just as continents float like
icebergs in the same way in what is called "isostasy".  As a result, as the
volcano builds, it depresses the plate at that location, much as a weight
on a water bed depresses the bed surface where the weight is.  Even small
islands have surprisingly large volumes, the volume of Tutuila where I
live, tiny compared to the main Hawaiian Islands, is over 2000 cubic
KILOMETERS of basalt rock.  Yeow.  Some shield volcanoes are enormous,
Mauna Loa and Mauna Kea on the Big Island of Hawaii are volcanoes that are
not only the world's tallest mountains (tallest from base, not highest
tops) and the volume of Mauna Loa alone is greater than the entire Sierra
Nevada mountain range in California, I've been told.  The volcano depresses
the plate underneath it, and so as the volcano builds it also sinks some.
I've read that there are fossil reefs on the side of the Big Is of Hawaii
that are over 1000 feet deep in the ocean, they formed at the surface and
were carried down as the volcano sank.  Obviously the volcano builds faster
than it sinks usually.  The sinking is slow compared to the building of the
volcano and so it is always behind and so continues for a while after the
volcano ceases erupting.  All this happens relatively quickly on a
geological time scale, it stops in a few million years.  This is not the
process that produces the reef sequence Darwin outlined, it takes about 12
million years at a minimum to produce an atoll.  The second process is that
the plate itself sinks.  The plate is formed at a mountain ridge that is a
spreading center, in the Pacific it is in the southeastern Pacfic.  Lava
erupts at the crest of the mountain range in between two plates that are
moving away from each other opening a crack between them.  The plate is
initially hot and the surface is relatively shallow.  The plate then moves
away from the spreading center (often at about 7-10 cm a year, about the
speed growth of toenails), carrying any volcanoes that form on the plate
with it, and as it cools it very slowly sinks.  Eventually it reaches a
trench, where the plate is subducted down into the earth.  Usually a trench
is reached within about 100 million years.  That might seem like a long
time, but the ocean floor is young everywhere compared to most continental
material, which can be well over 3 Billion years old in places.  The reef
carbonate at the bottom of the drill hole, right above the volcanic basalt
rock of the volcano it sits on at Einewetak Atoll in the Marshall Islands
where an atoll was first drilled, is 60 million years old.  This article is
talking about atoll formation on the order of a few hundred thousand
years.  That's on top of a stack of carbonate atoll that is up to at least
60 million years old.  What they are talking about is relatively
superficial and young.  Which doesn't mean it isn't real, it certainly is
very real.
      I await comment from a geologist or anyone who has read the review
article, will surely be a while before we hear.
      For an author of a book or annual review, which doesn't get peer
review, I'd suggest that in the long term, your reputation will be in
better condition if you try to get lots of comment voluntarily before
publishing, to try to avoid the situation the authors of this review may
find themselves in, of public criticism by experts in the field.  It is to
the long term best interests of authors to have peer review, even if in the
short term it can be very painful and without it can lead to significant
notoriety.  Best to avoid the wrong kind of attention in the long term, by
getting comments from experts and following their advice where possible.
That's just my personal opinion.
       So this will continue to be interesting to see how it unfolds.
       I think there is also a parallel with Darwin's theory of natural
selection.  Not having read all of Darwin's works, I'd lay a bet he never
said that his theory covered everything about evolution.  Indeed, he
himself not only wrote a book on natural selection, but also a complete
separate book on sexual selection.  A different mechanism, not as famous,
as far as I know  it is still supported by evidence.  It's why male
peacocks have such giant tails they can barely fly, and why male seals of
many species are huge compared to females.  He recognized very well and had
strong evidence that natural selection was not the whole story.  And it has
been added to further and probably will continue to be added to.  So there
is "genetic drift" which is random and in very small populations genetic
drift can be more powerful than natural selection.  And there is punctuated
evolution, sociobiology ("selfish gene") and probably others.  Nature is
more complicated than any one theory, and coral reefs are especially
diverse and complicated.  None of which proves that Darwin was wrong, and
natural selection is still well known to be one of the major drivers of
evolution.  And of course Wallace came to the same conclusion as Darwin on
natural selection at the same time, their first papers were read at the
same time, and Steven Jay Gould points out that a forester actually
outlined natural selection in print well before both of them.  But Darwin
spelled it out in so much detail with so much supporting evidence in his
book "The origin of species" that he became famous and we remember him as
the father of evolutionary theory.  By the way, there are a few
evolutionary processes that actually follow Lamarkian evolution, even
though he was long pilloried for an incorrect theory.  The latest is
"methylation" of DNA, an acquired genetic character that is passed on to
subsequent generations.  Currently a hot topic.
      Cheers,  Doug

On Fri, Oct 16, 2020 at 11:51 AM Douglas Fenner <
douglasfennertassi at gmail.com> wrote:

> or so says a new article:
> Popular piece:
> Study: Darwin's theory about coral reef atolls is fatally flawed
> http://news.rice.edu/2020/10/12/study-darwins-theory-about-coral-reef-atolls-is-fatally-flawed-2/
> Original review:
> The origin of Modern Atolls: Challenging Darwin's Deeply Ingrained Theory
> https://www.annualreviews.org/doi/10.1146/annurev-marine-122414-034137
> My thoughts, based on reading the popular article and the abstract for the
> review:
> Yes, if you define an "atoll" as a ring of coral at the surface, and you
> carefully ignore that it is on top of an accumulation of up to a mile of
> coral reef carbonate, which is in turn on top of a two mile tall volcano
> which all the evidence shows has indeed subsided with the ocean floor plate
> as it moves across the ocean, then yes, sea level fluctuations with the
> glaciation cycle are widely acknowledged to affect the coral reef
> structure.  It appears that maybe the new thing in this review is that the
> present ring is relatively young and built on top of the raised ring left
> from low sea level stands when rainwater was dissolving the carbonate in
> the center of the ring.  Actually, I don't think even that is new, though
> their being a flat topped bank in between time may be new.  This is a
> further embellishment on top of the Darwin theory, NOT a disproof of his
> theory, which is heavily documented.  The argument back then was whether
> there was a volcano under the carbonate, which drilling proved was correct
> and is no longer in doubt.
>      Perhaps by reading the entire review it will be clear that the review
> isn't saying that Darwin was wrong about subsidence and a volcano being
> under the carbonate, or that there was a sequence from fringing to barrier,
> to atoll, but even the title of the review implies it is.  But of course
> you attract a lot more attention saying that "Darwin was wrong."
>       What do geologists think?
> Cheers, Doug
> --
> Douglas Fenner
> Lynker Technologies, LLC, Contractor
> NOAA Fisheries Service
> Pacific Islands Regional Office
> Honolulu
> and:
> Coral Reef Consulting
> PO Box 7390
> Pago Pago, American Samoa 96799  USA
> “Don't think of it as the warmest month of August in California in the
> last century. Think of it as one of the coolest months of August in
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> <https://nature.us17.list-manage.com/track/click?u=2c6057c528fdc6f73fa196d9d&id=38d5d14948&e=190a62d266>
> The toxic effects of air pollution are so bad that moving from fossil
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> <https://nature.us17.list-manage.com/track/click?u=2c6057c528fdc6f73fa196d9d&id=c9f70ba54f&e=190a62d266> —
> even if climate change didn’t exist.  In the US alone, decarbonization
> would save 1.4 MILLION lives in the US alone.  And save $700 Billion a
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> https://www.vox.com/energy-and-environment/2020/8/12/21361498/climate-change-air-pollution-us-india-china-deaths
> "Already, more people die  <http://www.nws.noaa.gov/om/hazstats.shtml>from
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> ."
> https://www.npr.org/2018/07/09/624643780/phoenix-tries-to-reverse-its-silent-storm-of-heat-deaths

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