[Coral-List] Darwin was RIGHT in context of the times

Alina Szmant alina at cisme-instruments.com
Wed Oct 28 14:18:57 UTC 2020

Hi All:

I have been too busy to weigh in sooner but have been annoyed and disappointed by message after message that Darwin was WRONG about mid-oceanic atolls forming on top of subsiding volcanoes.  Think back to 1820s and a twenty-something Darwin exploring the expanses of the Pacific ocean. Coral reefs were known to scientists as structures associated with one landform or another.  And there they were,  coming across huge rings of coral reef in the middle of nowhere.  Darwin put 2+2 together to connect the dots between the range of mid-oceanic volanoes with little associated coral, to ones like Tahiti with a narrow fringing reef and shallow backreef lagoon,  to formations such as Bora Bora with a few volcanic rocks sticking up within a huge lagoon surrounded by coral reef, to atolls with no land in sight. In the 1950s, mostly associated with nuclear testing on Bikini and Eniwetak, scientists drilled 1500 m (or ft, can't remember units, but still a long way down) to find volcanic rock below a huge accumulation of coral limestone confirming Darwin's theory of subsidence.  Also found were intervals of subaerial erosion and remineralization that confirmed Daly's glacial control theory 's modification to Darwin's theory. Darwin wasn't trying to explain everything geology about coral reefs: he was motivated by these weird unexplained landless mid-oceanic coral reefs. Remember,  there was no sea level curve back.then. There were no isotope dating methodologies back then.  There was no plate tectonics back then. Just brain matter and creativity.

 In 1968 I took a term-long seminar about atolls at Scripps organized by faculty who had.just been or were getting ready to go, can't recall, on a major atoll expedition. The faculty were people like Menard, Newman and other notables. We reviewed all of the drilling data and other aspects of reef formation and had a grand time thinking about all this and how brilliant Darwin had been to recognize the process of mid-oceanic atoll formation.

 It seems rather petty that 50+ years later scientists are writing papers and using such negative titles for posts as Darwin was WRONG when in fact he was RIGHT in the context of what he was trying to explain.  He wasn't addressing structures such as the 'atolls ' of the Belize Barrier Reef or other types of atoll-like structures that formed due to local subsidence and sea level dynamics. He likely didn't know of their existence.

It is nice to see so.much recent interest in  coral reef geological processes on coral list because coral reef ecologists and environmentalists often forget to take the geological history of a site into consideration. But please have some sense of the scientific process in mind and how knowledge is the accumulation of blocks of new knowledge on top of old knowledge.  The new stuff wouldn't happen if the groundwork hadn't been laid down before them.

I agree with posts that point out how poorly informed too many scientists are these days because they don't dig into the older literature.  I keep seeing posts and claims about the first this and the biggest that by people who haven't bothered to read anything that doesn't pop up in Wikipedia or older than 2000.  As an oldster who grew up academically pushed to read back to the foundational works, this is a bad sign of how intellectual rigor is being lost.


Alina Szmant
CISME Instruments LLC

Sent from my Samsung Galaxy smartphone.

-------- Original message --------
From: Tomas via Coral-List <coral-list at coral.aoml.noaa.gov>
Date: 10/28/20 7:38 AM (GMT-05:00)
To: David Blakeway <fathom5marineresearch at gmail.com>
Cc: Coral Listserver <coral-list at coral.aoml.noaa.gov>
Subject: Re: [Coral-List] Darwin was WRONG about reef formation

Hi everyone,
Great comments by Walter and David regarding the recent atoll review.
Some of my most enjoyable times that I spent learning about coral reefs
was the times when I was reading the early works by some of the great
minds that came before us. Sadly we don’t see many references to these
great works in recent literature especially in reviews. You would be
surprised what you can learn from the past, and indeed some “new
discoveries” in coral reef science were actually discovered in not too
distant past buried in literature few had access to. My favourite
example is the early work by Sluiter (1890) who sunk 15 bore-holes sunk
into a fringing reef in Sumatra and found that the growth of this
fringing reef was initiated on soft substrate which was contrary to the
general assertion that coral reef initiation required a hard rocky or
volcanic basement. In 1931 a paper by Umbgrove (1931) actually mentioned
Sluiter’s 1890 study and commented that:

“The reef has not grown on a rocky volcanic substratum or against the
andesitic coastal lava, but rests entirely on the muddy bottom of the
bay, as is also the case with the reefs in the Bay of Batavia, The
Thousand-Islands, and the Spermonde Archipelago.”

However, the general assertion that hard substrate was required for reef
initiation lasted for decades till Hopley and Partain (1987) who wrote:

  “Reefs have long been regarded as requiring hard substrate for
initiation. However, there is increasing evidence that from North
Queensland reefs that the presence of even a muddy sedimentary structure
with positive relief may greatly enhance or speed up reef flat

Access to the early works has been made much easier so I would urge all
those that are starting their exciting careers in coral reef science to
reach back in time and read some of the great early works. Anyone
interested to get references for some of this early coral reef science
materiel can visit the following links:




  David Blakeway via Coral-List wrote:
> Doug - Their interpretation for the Maldives is that the carbonate
> sequence
> was all produced in shallow water, over the subsiding volcanic plateau.
> Deposition rates varied across the plateau, some areas remaining
> shallow
> and other areas drowning. The areas that remained shallow developed
> into
> flat-topped sea-level banks during a long period of relatively stable
> sea
> level just over 3 million years ago. Atoll morphology subsequently
> developed over the flat-topped banks, and is therefore independent of
> the
> deeply buried volcanic substrate. I think it is a good model, with some
> solid supporting evidence from the Maldives. But the article would be
> so
> much better if it exercised more restraint and balance; e.g. by
> conceding
> that there may be multiple paths to atoll morphology, by acknowledging
> that
> Darwin had already suggested some atolls develop from submerged banks,
> and
> by citing previous work apparently contradictory to their conclusions.
> By the way, Darwin's tentative explanation of the Maldives was to
> slowly
> submerge a large elongate island surrounded by a barrier reef, like New
> Caledonia. The reef "*...after repeated subsidences, would become
> during
> its upward growth separated into distinct portions; and these portions
> would tend to assume an atoll-like structure, from the coral growing
> with
> vigour round their entire circumferences, when freely exposed to an
> open
> sea." *Referring to these sub-atolls, he later says* "...these again,
> during long periods of subsidence, would sometimes become dissevered
> into
> smaller atolls.*" I know it is just logic, but sure seems like magic!
> On Tue, Oct 27, 2020 at 3:22 AM Dennis Hubbard
> <dennis.hubbard at oberlin.edu>
> wrote:
>> Thanks David:
>> Going back to a thread from a couple years back, this is the reason
>> that
>> extensive citing of the literature (and not just the most recent and
>> "hot"
>> articles) is so important.
>> Dennis
>> On Mon, Oct 26, 2020 at 10:57 AM David Blakeway <
>> fathom5marineresearch at gmail.com> wrote:
>>> The Droxler & Jorry article provides a valuable perspective but, as
>>> has
>>> been pointed out by others, it sells Darwin short. The article claims
>>> that
>>> most modern atolls have developed over flat-topped Pliocene banks,
>>> and
>>> therefore that Darwin’s fringing reef to barrier reef to atoll model
>>> is
>>> wrong. However, Darwin already knew his model did not apply to all
>>> atolls.
>>> For example:
>>> “*...if, therefore, corals were to grow up from a bank, with a level
>>> surface some fathoms submerged, having steep sides and being situated
>>> in a
>>> deep sea, a reef not to be distinguished from an atoll, might be
>>> formed..*.”
>>> (Darwin 1842, chapter 5)
>>> Furthermore, the article fails to cite a recent paper that describes
>>> a
>>> fringing reef to barrier reef transition at Tahiti, reconstructed
>>> from 35
>>> logged and dated cores (Blanchon et al. 2014; open access at
>>> https://www.nature.com/articles/srep04997).  Such selective citation
>>> is
>>> especially disappointing in a review article.
>>> An additional problem with the article, from my perspective, is that
>>> it
>>> invokes the antecedent karst hypothesis to explain the atoll rims. A
>>> more
>>> parsimonious explanation, developed by the first scientists to survey
>>> atolls in the early 17th century, is simply that corals and coralline
>>> algae
>>> grow better in the turbulent and well-oxygenated water on the outer
>>> edges
>>> of submerged structures.
>>> The karst hypothesis, in my opinion, is impeding coral reef science
>>> because it views reefs as passive structures – it denies the
>>> reef-building
>>> organisms any agency in creating reef form. We really need some young
>>> ecologists to take reef geomorphology forward!
>>> David Blakeway
>> --
>> Dennis Hubbard - Emeritus Professor: Dept of Geology-Oberlin College
>> Oberlin OH 44074
>> (440) 935-4014
>> * "When you get on the wrong train.... every stop is the wrong stop"*
>>  Benjamin Stein: "*Ludes, A Ballad of the Drug and the Dream*"
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