Catastrophism vs. Uniformitarianism

1. Catastrophism vs. Uniformitarianism Paroxysms vs. Same old, same old

2. Some of the Major Players in the Debate Catastrophism Kirwan, de Luc ( ~ 1800) -- required strict concordance with biblical flood Cuvier (~ 1810s-1820s) -- Paris Basin: periodic inundations of the sea; fossils Elie de Beaumont (~ 1820s -1840s) -- mountain building thru catastrophic uplift Buckland (~ 1820s-1830s) -- influential teacher of Lyell and Murchison Collector of fossils, theologian. Early on, believed in the biblical flood. Uniformitarianism Lyell (~1830s-1850s) -- Principles of Geology (1830-33) was one of the most influential geologic books of all time. Darwin (voyage of the Beagle, 1835) -- took a copy of freshly published vol. 1 of Principles with him on the Beagle. He observed an earthquake in Chile; calculated that the Andes could be raised in ~ 1 Ma.

3. Uniformitarianism vs Catastrophism Uniformitarianism -- actualism -- "the present is the key to the past“ (Geike) Refers partly to a method -- study of present-day processes as a means of interpreting past events -- assumes constancy of physical laws Refers also to a geologic theory(Are there “laws” in geology, as in chemistry and physics?) -- geologic processes are natural (not supernatural), slow, operate unchanged over long time periods at about the same rate, and deal with the same materials -- no directionality in geologic time (e.g., earth is not cooling – Kelvin took exception) -- Lyell early on rejected the notion of organic change (evolution); later accepted notion of evolution, but not the process of natural selection Catastrophism -- recent geological history strongly decoupled from the past --- geologic history is marked by long periods of quiescence interrupted by catastrophic upheavals of the land and/or inundations by the sea --- the last catastrophe was often (but not always) linked with the Biblical flood. Diluvialism. --- “…creative power transcending the operation of known laws of nature” (Whewell) --- evidence: apparent sudden disappearance of fossils, frozen mammoths, glacial erratics…

4. James Hutton (1726-1797), Scottish “Gentleman Geologist” “The present is the key to the past.” Geike (1905). The Founders of Geology, p. 299. “Hutton’s unconformity at Siccar Point, where almost-vertical Silurian layers are overlain by almost horizontal layers deposited about 100 million years later.” James Hutton James Hutton in the field. Contemporary sketch.

5. Some of Hutton’s Ideas Later Led to Principle of Uniformity -- His paper before Royal Society of Edinburgh (1785), which led to his publication of the same name, i.e., Theory of the Earth; or an Investigation of the Laws Observable in the Composition, Dissolution and Restoration of Land upon the Globe. -- Earth is a system of several parts (solid body, aqueous body, elastic fluid); not disorder and confusion. -- Soil is the product of the destruction of solid rock, part of the cycle of weathering, erosion, deposition. -- Fossils indicate marine deposition of the enclosing rocks. -- There must be a mechanism by which to raise the floor of the ocean and reveal what had been deposited. -- Unconformities document the cyclicity of such deposition and uplift. -- Supposing that the forces of nature have always operated as they do now, we can estimate elapsed time. -- Therefore, to understand that which occurred without our observation, we should turn to present processes. -- It is unnecessary to call upon supernatural causes for the geologic features we see. -- Yet, there is the appearance of “a fabric, erected in wisdom, to obtain a purpose worthy of the power…” -- “…in nature, we find no deficiency in respect of time, nor any limitation with regard to power.” -- Comparison of recent maps of coastlines with maps from Greek and Roman times shows no change. -- All evidence points to the immensity of geologic time, but without evidence of a specific beginning time. Hutton’s ideas that were not accepted later: 1) fusion of sediments to explain lithification, 2) “cataclysmic rate” for the uplifts that produced the rocks we see, and 3) that the same species of organisms have existed throughout all time [Hutton actually had not studied fossils enough to make this (incorrect) generalization].

6. Georges Cuvier (1769-1832), French Paleontologist -- Cuvier was actually an anatomist by training. -- History of life on earth was recorded in fossils within rock strata. -- Described the succession of fossils in Paris Basin. -- Realized each rock unit had a unique assemblage of fossils. -- The older the rocks, the fewer the species like those found today. How did Cuvier arrive at a catastrophist view of earth history? -- He realized that extinction had been common in past eras. -- One species would disappear and another arise in the strata. -- If species do NOT transmute, then catastrophes occur: boundaries. -- He perceived floods, droughts, etc. between strata. -- “New” species required successive creations; biologic; higher levels. -- This dynamism is called catastrophism. Megatherium, a giant ground sloth. Described by Cuvier. Stratigraphy of the Paris Basin

7. William Buckland (1784-1856), British Geologist and Paleontologist -- Captivating teacher; quite a character. Clergyman. -- First Professor of Geology at Oxford University. -- He began the earliest scientific study of dinosaurs (many samples from Mary Anning) -- Emphasized field work, unlike predecessors. -- Believed study of geology revealed divine purpose. -- Emphasized how well adapted animals were to their surroundings; Darwin would interpret differently. --Believed ”convulsions” or ”revolutions” inferred from fossil and stratigraphic record indicated directionality. -- Believed in the biblical flood and its global extent. Looked for supporting evidence. -- Was excited to defend this idea when local miners reported a large cave in Yorkshire that had a huge assortment of bones. He initially attributed these bones to the biblical flood. -- Buckland both identified the bones (lions, rhinos, elephants, hyenas, hippos) and reasoned that a pack of hyenas had used the cave as their lair and dinner table. Well regarded for this. -- Buckland’s personality and contribution of NEW kinds of data won the day for catastrophists.

8. Buckland’s idiosyncrasies: -- His unusual attire. -- The pets at home. -- The special dinners for guests. -- His pronouncements when visiting local tourist spots. Buckland’s renown: -- “Chief architect of the catastrophist synthesis” (Gillispie, 1959, p. 98) -- He considered geology “the efficient Auxiliary and Handmaid of Religion” (1837, p. 441) William Buckland, 1823 Buckland fossil table at the Lyme Regis Museum. What are these fossils that have been so carefully mounted, sectioned, and polished?

9. The Intellectual Situation of Geology in the 1820’s -- Geology was an exciting science: newspapers, discussions. Excitement of catastrophes (earthquakes, tsunamis, volcanic eruptions). -- Great interest in fossils, not only by professionals such as Buckland, Conybeare, Sedgwick, and Murchison. -- British geologists almost universally embraced catastrophism. -- They believed that the earth was older than previous geologists, except Hutton, had thought. -- It appeared that Biblical statements and geological evidence in fact were in agreement on the latest catastrophe, i.e., the Mosaic Flood. -- “The flood itself was not a speculative matter.” (Gillispie, 1959, p. 91) -- Viewed geologic history in two periods: Antediluvial and Post-Diluvial. This is the notion of the diluvialists. -- By 1830, many had re-directed Hutton’s support of plutonism into a defense of catastrophism. -- M. King Hubbert (1967, in Cloud, 1970) claimed a “period of confusion” [c.f. Kuhn] in geology between time of Hutton’s (1788) and Lyell’s (~ 1830) writings.

10. Two Main Lines of Evidence for Catastrophism -- Large-scale mechanical violence: vulcanism, building of huge mountain chains. Inferred that sizes of forces must have been uncommonly large; different from today’s. Erosion and denudation: apparently huge torrential rains and accompanying floods. -- Complete changes in the observable fauna (of great interest to Buckland). Noted there was an order of succession to fauna found stratigraphically. Claimed this order followed that of their creation: fish, amphibians, reptiles, mammals. “If there is any circumstance thoroughly established in geology, it is, that the crust of our globe has been subjected to a great and sudden revolution, the epoch of which cannot be dated much further back than five or six thousand years ago...” Cuvier’s Essay on the Theory of the Earth. (From Gillispie, 1959, p.101)

11. Sir Charles Lyell (1797-1875), Scottish Geologist Pillars of the temple at Pozzuoli (Italy), from the frontispiece in Lyell’s Principles of Geology (1832). Evidence that former sea levels differ from today’s. Corrosion bands on each pillar indicate submersion. After the temple was built, there was downwarp and later uplift associated with volcanic activity. Sir Charles Lyell, born in Scotland to a wealthy family. In the 1840s, Lyell traveled to the US and Canada. Lyell’s Principles of Geology came 42 years after Hutton’s Theory of the Earth.

12. Development of the Principle of Uniformitarianism -- “If Buckland feared that without cataclysms there was no God, Lyell was as fundamentally apprehensive lest, without uniformity, there be no science.” (Gillispie, 1959, p. 121) -- Revealing subtitle of Lyell’s famous book – Principles of Geology: Being an Attempt to Explain the Former Changes of the Earth’s Surface, by Reference to Causes Now in Operation. Some of the uniformitarianist arguments: -- Evidence of gradual (not rapid) downcutting of rivers was seen – Not sensible to call on one flood to account for all types of sediments (geologists had been conceptually lumping ALL types of organic and mineral detritus together) – Violence of floods that scoured the landscape and moved huge boulders was not consistent with the biblical account of the flood, in which waters rose and sank rather placidly – Scrope pointed out that volcanic deposits bore no close ties with any flood(s); old deposits could be explained by current rates of volcanic eruption

13. Lyell’s Development of the Concept of Uniformitarianism -- Man naturally has come to recognize a “regular course of events” rather than special causes -- “The philosopher at last becomes convinced of the undeviating uniformity of secondary causes” -- “…confidence which we feel in regard to the permanency of the laws of nature.” -- “…enable us to reason from analogy, by the strict rules of induction,…events of former ages” -- Beginning and ending to earth history: followed Hutton – no evidence of either. -- Rates of processes in past vs. present: Successive “periods of disturbance and repose” in every region “…uniform as regards the whole earth.” Shifts in the most intensely affected region. -- Principle of Uniformity with respect to animal and plant life: Rejected Lamarck’s theory of gradual development or transmutation Favored permanency of species Antiquity of Man compared to biblical account; more recent origin of man than other species Had trouble reconciling Principle of Uniformity with his idea of recent origin of man -- Eliminated reliance on biblical chronology to understand/order geologic history Lyell did not deny change during geologic history; he simply said that those changes occurred uniformly over time.

14. Various Statements of the “Principle” of Uniformitarianism Quoted from Hubbert (1967) Uniformity and simplicity: GSA Special Paper 89, pp. 3-33. -- The present is the key to the past. -- Former changes of earth’s surface may be explained by reference to causes now operating. -- The history of the earth may be deciphered in terms of present observations, on the assumption that physical and chemical laws are invariant. -- Not only are physical laws uniform, that is, invariant with time, but the events of the geologic past have proceeded at an approximately uniform rate, and have involved the same processes as those which occur at the present. Acceptance of the above ruled out: Idea that earth had been very hot when first formed and had cooled over geologic time Changes in climate Progression of the fossil record from simple to complex. If full range of species had always existed, then mammal fossils should be found in the Cambrian; we just haven’t looked in the right place. Directionality, “progress” Restriction of acceptable processes to those operating in the present rules out catastrophes on methodological grounds.

15. Some Final Thoughts on Catastroph-Uniform. Debate Why did it take so long to reject catastrophism? -- The study of the earth unfortunately lent itself to interpretations of miracles (supernatural), catastrophes, etc. – Previous lack of appreciation for the huge amount of TIME available to cause the changes whose relics were now observed. So, people called on deviations from current processes. – Unfortunately, what we now see is on land, but most of the globe is under water. We get to see the most changed, preserved features and fossils. Gradualism more apparent in marine sequences. Segue to future debates -- Reflection on upcoming Darwinian debate. Lyell COULD have pulled together the notions of progress and uniformity (as illustrated in geology) to support “transmutation of species” and thereby replace the catastrophist notion of “successive creations” of species. In other words, he could have eliminated the catastrophist view in biology just as in geology. -- Ideas did change. When Buckland wrote his 2-volume work for the Bridgewater Treatise, he never mentioned the deluge. Catastrophism had lost its most popular catastrophe.

16. Drawbacks to Uniformitarianism • "Strict uniformitarianism may often be a guarantee against pseudo-scientific phantasies and loose conjectures, but it makes one easily forget that the principle of uniformity is not a law, not a rule established after comparison of facts, but a methodological principle, preceding the observation of facts . . . It is the logical principle of parsimony of causes and of economy of scientific notions. By explaining past changes by analogy with present phenomena, a limit is set to conjecture, for there is only one way in which two things are equal, but there are an infinity of ways in which they could be supposed different." Hooykaas, R. (1963). The Principle of Uniformity in Geology, Biology, and Theology (2nd impression). London: E.J. Brill, p. 38.

17. Uniformitarianism Made Catastrophes an Anathema • “We postulate… that the largest… Missoula Flood resulted from a cataclysmic failure of the impounding ice dam of glacial Lake Missoula. This large release may have been the result of a complete rupture of the ice dam.” (Jim O'Connor and Victor Baker, Geological Society of America Bulletin, 104 (3) p. 267). • “An interesting part of the Missoula Flood story is that even though a great deal of the earth’s surface in the northwestern part of the United States was shaped by this flood, for many years after the evidence was first reported geologists refused to believe it had ever happened. Why? The question of where the water had come from entered in, but mostly they refused to believe because uniformitarianism blinded them to the evidence.” (Thomas Heinze) • "Bretz knew that the very idea of catastrophic flooding would threaten and anger the geological community. And here's why: among geologists in the 1920s, catastrophic explanations for geological events (other than volcanoes or earthquakes) were considered wrong minded to the point of heresy." p. 42. • "Nearly 50 years had passed since Bretz first proposed the idea of catastorphic flooding, and now in 1971 his arguments had become a standard of geological thinking." p. 71 (Allen, E. A., et. al, 1986, Cataclysms on the Columbia, Timber Press, Portland, OR.)

18. Catastrophism vs. Uniformitarianism Lyell

19. Contemporary sketch Joseph Black and James Hutton, labeled as “philosophers” (from Rudwick, 2005). The term “scientist”, rather than naturalist or natural philosopher, was yet to arise. Other good references (see also the footnotes to Hallam’s chapter): Gillispie, C.C. (1959) Genesis and Geology: A Study in the Relations of Scientific Thought, Natural Theology, and Social Opinion in Great Britain (1790-1850). New York: Harper & Row. Hubbert, M.K. (1967) Critique of the principle of uniformity. In C.C. Albritton, ed. Uniformity and Simplicity (GSA Special Paper 89), pp. 3-33.