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

Dennis Hubbard dennis.hubbard at oberlin.edu
Thu Oct 29 15:50:20 UTC 2020

Hi Alina:

Thanks from another "oldster". I remember ranting to students about how
amazing it was that Darwin envisioned the three-dimensional nature of
atolls when he could not get any higher than the crows' nest. And remember
that, when faced with the prospect of sailing around the Horn or walking
over the spine of South America, he set out on foot.... so I'm guessing
that, with his chronic seasickness, he never ventured up the mast. He did
not have the benefit of NASA imagery and had to think about the
three-dimensional nature of what he was seeing from the deck of the *Beagle*
without the incredible resources that we all take for granted (just think
about how incredible Google Earth is... and how little you've thought about
that as you hit that tab on your laptop).

One thing that makes all of this even more incredible to me is that, in one
of his classic memoires, Darwin explained that he did not actually come up
with his atoll theory while on the *Beagle*. He had apparently already
formed his ideas by looking at charts and thinking about what they were
telling him about the likely mechanisms at work. Despite his tremendous
contributions to how we think about evolution (if you want to feel real
awe, google "Darwin I think" and open one of the images from his diary),
Darwin preferred to "geologize". The bottom line with respect to this
thread was that he saw the process as one of subsidence as new volcanos
moved away from their hotspot origin. Without the benefit of plate
tectonics, he did not have a mechanism to explain either the movement or
the subsidence. But, he still reasoned correctly about the underlying
processes responsible. The bottom line is that Darwin was NOT wrong; his
understanding of the driving forces was just not complete. That does not
detract from the brilliance of his mind.

He departed from England with one book in his possession  - volume 1 of
Charles Lyell's classic *Principles of Geology*.... and left instructions
to send ahead the following two volumes as they were published. It is an
incredible read that remains incredibly relevant even though it was
published more than 10 years ago.



On Wed, Oct 28, 2020 at 4:05 PM Alina Szmant via Coral-List <
coral-list at coral.aoml.noaa.gov> wrote:

> 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.
> Best,
> 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
> development.”
> 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:
> https://www.researchgate.net/publication/301883384_Tomascik_T_A_J_Mah_A_Nontji_M_K_Moosa_1997_Chapter_Six_Coral_Reef_Origins_The_Theories_In_The_Ecology_of_the_Indonesia_Seas_Part_I_pp_207-232_Singapore_Periplus_Editions_HK_Ltd
> https://www.researchgate.net/publication/327606240_Tomascik_T_A_J_Mah_A_Nontji_M_K_Moosa_1997_References_In_The_Ecology_of_the_Indonesia_Seas_Part_II_pp_1265-1353_Singapore_Periplus_Editions_HK_Ltd
> Cheers,
> Tom
>   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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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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