Mark Gaffney explores the ‘extralimital anomaly’ of mollusc shells in the Americas, a hitherto under-researched area of science that supports Charles Hapgood’s theory of crustal displacement.
I first encountered empirical evidence supporting Charles Hapgood’s theory of crustal displacement while reading Charles Darwin’s 1846 book about the geology of South America.i Evidently, the well known French naturalist, Alcide d’Orbigny, had shared this important evidence with Darwin during the preparation of his book. d’Orbigny, a disciple of George Cuvier, preceded Darwin to South America, and subsequently published a detailed account that Darwin called “a most important work.” ii It’s unclear whether the two men ever met, but they corresponded over a period of years. Darwin cites d’Orbigny numerous times in both of his books about South America, and in a footnote writes that d’Orbigny’s research placed him “on a list of American travellers second only to Humboldt.”iii
Darwin included the data in a table along with a detailed discussion.iv I was stunned when I saw this material. It was also clear at a glance that Darwin did not understand what had passed into his hands. The evidence was not limited to a few scraps or observations pertaining to mollusks, but amounted to an entire data-set. True, shellfish are not sexy like saber-toothed tigers and woolly mammoths. But the study of mollusks nonetheless was on a solid scientific footing by the 1830s. This may have been due, in part, to the universal popularity of beach combing and collecting among amateur enthusiasts and trained scientists alike. We humans have always been fascinated with sea shells and love to collect them, whether they find the specimens on a beach, or in a sedimentary deposit on a mountain top.
It is noteworthy that Darwin’s associate, Charles Lyell, drew heavily upon this science in the course of identifying the different epochs of the Tertiary. Lyell applied a statistical method of his own design, which enabled him to distinguish the relative percentage of surviving versus extinct mollusk populations.v The early editions of his Principles of Geology (Volume Three) actually included a 65-page appendix with tables listing innumerable mollusk species. The innovation became known as statistical palaeontology, and although the approach has since gone out of fashion—modern editions of the principles are heavily abridged and do not include the tables—present-day science still owes a substantial debt to the early work on mollusk taxonomy and palaeontology accomplished by Lyell, d’Orbigny, and many others.vi
My excitement mounted as I studied the table in Darwin’s book and eagerly devoured his discussion. The basic facts are easy to summarise. Mollusks tend to live in communities—the standard technical jargon is “faunal assemblages”—and fossil beds of these communities are occasionally found in a pristine state of preservation. Such finds are rare because ocean surf is a powerful destroyer of seashells. Fortunately, due to the Andean uplift that Darwin also describes in his books, a number of these old faunal beds were discovered in pristine condition. On several occasions, Darwin himself found former beaches which had been raised up as much as a thousand feet above the present-day shore.
I have included a facsimile of the original table with all of the relevant data. It summarises the joint collaborative efforts of d’Orbigny and another well-known collector, Hugh Cuming, who had gathered specimens of 79 different species from the late Pleistocene at two principal sites on the Chilean coast: Coquimbo (30 degrees S latitude) and Navidad (34 degrees S latitude). Although many of the specimens were of extinct species, the collection included 12 living genera which are listed in the table. The two columns at the right indicate the latitude at which the specimens were collected, and the southernmost latitude at which the genera may still be found.vii
My jaw dropped as I studied the table. Notice the conspicuous disparity between the latitude at which the fossil specimens were gathered, compared with the latitude at which they are presently found. Nearly all of the extant genera had relocated far up the coast.
Mollusks are extremely fussy about where they live, and water temperature is the most important factor defining their habitat. Shellfish require a narrow temperature range, outside of which they simply are not found. Each species has slightly different requirements. When I crunched the numbers, based on the data compiled in the table, I calculated that the average habitat displacement to the north was 24.4 degrees of latitude. Given 68.7 miles per degree of latitude in the equatorial zone, this means the mollusks on average had migrated northward about 1,683 miles to warmer equatorial waters. Some had relocated as far north as Ecuador.
Before I proceed, I should mention that mollusks have very limited mobility. Unlike fish, they cannot swim. However, when they reproduce, they pass through a tiny larval stage, and these larvae are able to hitch a ride on ocean currents over considerable distances. Evidently this is how the various species relocated more than a thousand miles up the coast of South America, at the end of the Pleistocene.
The mass migration greatly intrigued Darwin, for he writes:
“the first impression….is that the climate [where the fossils were collected] must formerly have been warmer than it now is.”viii
Having raised the key question, Darwin then unaccountably begins to hedge, citing cases and evidence which, looking back today with the benefit of 20-20 hindsight, seem weak and unconvincing. For example, Darwin mentions the exceptional case of Voluta at the bottom of the list, which apparently did manage to adapt to the same altered, i.e., cooler, water temperatures that drove the other warm water loving species north toward the equator. At present, Voluta is only found south of 43 degrees which is approximately the latitude of the town of Chonchi on the island of Chiloe, one of the large islands in the archipelago of southern Chile. In his account, Darwin shows great reluctance to formulate an opinion about what it all could mean. In a rambling discussion on the next page, he refers to his colleague, Mr. Lyell, who was always known to counsel caution when confronted with anomalous data, to which Lyell often attributed local factors. We will encounter the same tendency again, very shortly.
How then do we account for the fact that warm-water loving mollusks were formerly found at southern latitudes of the Pacific coast, a region that today is significantly cooler? Did the temperature of the nearby Humboldt ocean current change at the end of the Pleistocene? Insofar as I have been able to determine, there is no evidence for this. The ability of the exceptional genera Voluta to adapt to cooler temperatures only clarifies the rule.
Indeed, the average 1,683 mile migration of eleven genera of mollusks northward stands in silent witness to an extraordinary event. And this should also have been obvious in the 1840s. A paradigm-busting data set had fallen into Darwin’s lap, pointing toward a mind-boggling conclusion: that the crust of the Earth had shifted, at the close of the Pleistocene, by approximately the same distance the mollusks had migrated. But Darwin was unable to make this leap of imagination, however logical, because doing so would have required him to think outside the box. The great man who very nearly explained evolution could not shake himself free from the scientific model that held him fast. Darwin remained a prisoner of his own beliefs and, as we are about to learn, in this he was far from alone.
The extralimital anomaly
On a hunch, I did a Google search and within minutes was staring at several scientific studies of mollusk assemblages on the west coast of North America. As I read, I was blown away. The first paper that I examined, published in 1966 by W.O. Addicott, a scientist working for the US Geological Survey, describes a
“heretofore unrecognized late Pleistocene molluscan province characterized by northern mollusks and foraminifers (i.e., linear and spiral shelled mollusks) that are no longer living off the central California coast.”ix
The paper goes on to describe virtually the same phenomenon reported by Darwin in 1846, except that in this case the northward migration of mollusks was from warm water to cold (instead of from cold water to warm) and had occurred not in South America but on the west coast of the United States. By this point, as you might well imagine, I was completely engrossed.
Undisturbed fossil beds at several locations in central California, one at Santa Cruz and two at Point Año Nuevo a few miles up the coast, documented the southernmost outpost of a community of at least 80 species of late Pleistocene mollusks, many of them still living, that are no longer found in the area but presently inhabit the cooler waters of Puget Sound and the B.C. coast as far north as Alaska.x The data presented by Addicott indicates that these surviving late Pleistocene mollusks had migrated from the vicinity of Santa Cruz northward by a minimum of 11 degrees of latitude, a distance of 755 miles.xi
Today, water temperatures in Puget Sound are 4 degrees centigrade cooler than the coastal waters at the latitude of Santa Cruz. Evidently the cool water loving mollusks had moved north in search of their preferred habitat, after the coastal waters of central California warmed up. The obvious question that Darwin failed to pursue is: what caused this warming? Surely the answer is: the same event that caused the cooling of the coastal waters of Chile.
Writing in 1966, Addicott apparently had no knowledge of the South American case reported by Darwin in 1846, because he credits discovery of the so called “extralimital anomaly” to a US-based scientist, Ralph Arnold, who reported it in 1908.xii Nor have things improved in this respect. A 2014 monograph on the issue published by three scientists, Daniel R. Muhs, Lindsey T. Groves and R. Randall Schumann, makes no mention of Darwin.xiii Nor do the three scientists display any awareness that the phenomenon under discussion is not exclusive to North America.
In their paper, the scientists thoroughly review various local and regional factors proposed by other experts to explain why sea water temperatures along the central California coast warmed up since the late Pleistocene. The possible factors they cite for this include the upwelling of cold water, effects of winds and currents, changes in the geography of the coast over time, as well as the reworking (i.e., alteration) of fossil beds. To their credit, the authors reject all of these, concluding that
“although many mechanisms have been proposed….no single explanation seems to be applicable to all localities where thermally anomalous faunas have been observed.”xiv
Muhs, Groves and Schumann were correct in 2014 to dismiss all of the proposed local or regional explanations. Because surely a temperature-driven anomaly that effects two continents and stretches across two hemispheres of the Earth cannot properly be described as local or regional. The same event that cooled the coastal waters of Chile probably also caused warming of the coastal waters of central California. Both cases appear to be linked and also synchronised. When faced with a global mystery, does a local or regional solution suffice? Probably not. No, one should tailor the search and the solution to the scale of the phenomenon. In this case, the data surely indicates the need to think globally.
The extralimital anomaly therefore does not date to fieldwork by American scientists in the early years of the twentieth century, but to 1846, the year Darwin published his book on the geology of South America. Notice, this would make the anomaly a whopping 170 years old, and this is probably a conservative estimate. More likely, South American collectors knew about the mysterious northward migration of mollusks in the 1830s, and possibly as early as the 1820s. We know that d’Orbigny arrived in Chile in 1826. Notice, this would make the anomaly more than 190 years old!
How many other scientific fields can lay claim to such an extended legacy of failure? Probably few to none. But perhaps the deeper issue is how and why trained experts can have misfired so badly. The extralimital anomaly has not only eluded scientific explanation up to the present day, but in the course of doing so has also managed to stay completely off the radar. At present, insofar as I can tell, outside the tiny field of malacology (the study of mollusks) the anomaly remains virtually unknown, a regrettable fact which I attribute to over-specialisation.
The unfortunate modern-day reality is that our universities train science students to think more and more about less and less. As a result, students by and large never gain the invaluable experience of thinking outside the box; and very few of them go on to develop a holistic approach or an interdisciplinary career. Yet, if there was ever a problem that called for an interdisciplinary approach, it is this one. Sadly, when I contacted the three authors of the 2014 paper to alert them about the larger ramifications, I encountered only silence. I never heard back, not so much as a peep. Not one of the scientists extended me the simple courtesy of a brief acknowledgment. Did they dismiss me as a crank, or a conspiracy nut?
I would be guessing about their motives and their state of mind if I commented further, so I will refrain. Nonetheless, it does appear that the leading authorities in the field are prisoners of their scientific training and beliefs. In this, things have not changed since the time of Darwin. The present generation of experts who write papers about the extralimital anomaly have yet to learn about its actual history and its true scope. As I write in 2019, the matter remains anomalous, as ever.
i Charles Darwin, Geological Observations on South America, originally published 1846, in the Classic Reprint Series: On the Structure and Distribution of Coral Reefs; also, Geological Observations on the Volcanic Island and Parts of South America Visited During the Voyage of the Beagle (Forgotten Books, 2012), pp. 406-412.
iii Charles Darwin, The Voyage of the Beagle (New York, Random House, 2001), p. 84.
iv Geological Observations on South America, pp. 406-412.
v For an excellent discussion see Stephen Jay Gould, Time’s Arrow, Time’s Cycle (Cambridge Mass & London, Harvard University Press, 1987).
vi M.J.S. Rudwick, “Charles Lyell’s dream of statistical paleontology,” Paleontology, 21, 1978, p. 225-244.
vii Geological Observations on South America, p. 406-412.
ix W.O. Addicott, “Late Pleistocene Marine Paleoecology and Zoogeography in Central California”, Geological Survey Professional Paper 523-C, US Government Printing Office, 1966.
x Ibid., p. C-9.
xi Ibid., p. C-10.
xii Ralph Arnold, “Descriptions of new Cretaceous and Tertiary fossils from the Santa Cruz Mountains, California”, US Natl. Musc. Proc., Vol 34, 1908, no. 1617, p. 345-390.
xiii Daniel R. Muhs, Lindsey T. Groves and R. Randall Schumann, “Interpreting the paleozoogeography and sea level history of thermally anomalous marine terrace faunas: a case study from the Last Interglacial Complex of San Clemente Island, California”, Monographs of the Western North American Scientist, Vol. 7, 8th California Islands Symposium, Article 6, 2014.