The Discovery of Time We have made great progress in discovering the history of life on Earth



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The Discovery of Time

  • We have made great progress in discovering the history of life on Earth

  • But before we could discover the history of life, we first had to discover time itself

  • in the 19th Century was a remarkable revelation

  • The history of life was no longer just the history of man

  • All of human history could now be seen in its proper perspective - a tiny island in a vast sea of prehistoric time

  • Many ancient philosophers pondered the history of life

  • Aristotle, Empedocles, Lucretius, other Greek and Roman philosophers were concerned with how life began, how species were formed

  • Early Christians were convinced that the world was only 6,000 years old

  • The Chronographia of Julius Africanus was instrumental in this rather arbitrary choice of the Earth’s beginning

  • Drew on the ancient Jewish tradition of the millennium

  • Messiah would arise to rule the Earth for 1,000 years, culminating in the end of the world

  • Chronographia represented history as a week, in which each day was 1,000 years

  • First six days of history covered from the start of creation to the 2d coming of Christ

  • Followed by the seventh day of Christ’s millennial reign on Earth

  • Figured 5,500 years from creation to the birth of Christ, 500 AD would be the second coming = 6,000 years

  • Archbishop James Ussher arrived at the same figure in a more pedantic fashion

  • Calculated the generation time of the “begats” in the Bible, times average lifespan

  • World was created in 4,004 BC

  • John Lightfoot - scholar at Cambridge, went even further than Usher

  • Announced that man himself had been created on Sunday, October 23d, 4004 B.C., at precisely 9:00 A.M.

  • Way too early in the morning - explains a lot…

  • Few people thought to question this date

  • Later went to great lengths to support it

  • Discovery of time is the history of human efforts to accommodate geological observations to their personal religious beliefs

  • Two basic discoveries were instrumental in

  • Principle of superposition of strata

  • Principle of faunal succession

  • Principle of superposition of strata

  • In a stratigraphic sequence, each layer of rock is younger than the rock it rests upon, and older than the layer of rock that rests upon it

  • Principle of faunal succession

  • Within any layer of rock (stratum), different types of fossils succeed one another in the same relative order

  • These two ideas may seem fairly obvious to the modern mind, but it took decades of observation and argument to establish them

  • At the start of the 17th Century, people were not even aware that fossils were the preserved remains of animals

  • Consider the lowly shark’s tooth…

  • Sharks have a skeleton made of cartilage - doesn’t preserve well, like bone

  • Only fossilized remnant of sharks is their teeth, one of the most commonly found fossils

  • Sharks teeth were widely known in antiquity

  • Thought to be a geological artifact

  • Called glosso petrae or “tongue stones”, due to their vague resemblance to the human tongue

  • Pliny’s Natural History says:

“Glossi petra resembles a man’s tongue, and grows not upon the ground, but in the eclipse of the moon falls from heaven, and is thought by magicians to be very necessary for panderers and those that court fair women.”

  • Another legend attributes them to St. Paul’s visit to the island of Malta (59AD)

  • Shipwrecked, bitten by a viper, St. Paul cursed all the snakes on the island, turned the snakes’ teeth to tongue stones

  • “St. Paul’s tongues” still an island folk remedy

  • Fossils were called “lusus naturae” in the 17th Century, sports of nature

  • Very hard for people to accept the existence of a vanished age

  • Two early pioneers - Nicolas Steno and Robert Hooke

  • Nicolas Steno - one of the first to grasp the length of time required to create the geology of the modern world

  • Noted the resemblance of tongue stones to the teeth of a great white shark whose head he had acquired for dissection

  • Studied the geology of Tuscany, tried to reconcile local geology with the Biblical Flood

  • Described the process by which the remains of ancient organisms could become buried in layers of rock

  • Steno was also one of the first scientists to consider how objects could become embedded in other objects (fossils in rocks)

  • One of the first to realize that layers of rock were formed as horizontal strata, later deformed into other shapes

  • Steno claimed that

  • Each stratum is deposited from fluid upon a solid subjacent surface--hard (solid) fossils may be incorporated into soft (loose) sediment at this stage

  • Each stratum is laterally continuous and approximately horizontal

  • Steno claimed that

  • Superposition (stacking) of strata takes place according to age

  • Any deviation is due to later alteration--earthquake, volcano, etc

  • Wrote Prodromus in 1668

  • Means “introduction”, planned much more detailed work but abandoned it

  • Steno converted to Christianity in 1667, became a bishop

  • Gradually turned away from science

  • Now on the long road to sainthood

  • Would be the first scientist to become a saint

  • Ironic, considering he abandoned science because it conflicted with his religious beliefs!

  • Prodromus implied a great deal of time was required for the long process of laying down several strata of rock

  • Too subtle for the church to notice, book was given the Imprimatur

  • Papal permission to publish, not given to books that cast doubt on issues of faith

  • Robert Hooke - another early pioneer in

  • Hooke was a physicist, inventor - universal joint, wind gauge, balance spring for watches…

  • Discovered the cellular structure of plants while examining thin slices of cork

  • Hooke was the son of a clergyman, educated for the ministry

  • Preferred to spend his time drawing, making complex mechanical toys

  • Set out to prove that “petrifactions” (fossils) were the remains of organisms

  • Hooke pointed out that the same types of fossils are found in different types of rock

  • Unlikely that they grew from the rocks, or different rocks would have different types of fossils

  • If we uncover coins or urns buried in the soil, we don’t attribute them to some “plastic faculty” of the earth

  • Should also accept that sea shells and similar objects found in rocks are real natural objects, not sports or artifacts

  • Ammonites are often found as fossils

  • Ammonites are extinct cephalopods, with coiled shells similar to the chambered Nautilus

  • Why were there no ammonites around today?

  • Maybe ammonites were still around, but only existed in some remote area, undiscovered

  • Maybe they had died out a very long time ago…

  • Hooke wrote in 1705:

“There may have been many…species of creatures in former ages, of which we can find none at present; and that it is not unlikely also but that there may be diverse new kinds now, which have not been from the beginning.”

  • Hooke worked in the 1650’s as an assistant in the Oxford lab of the famous chemist Robert Boyle

  • Part of a young group of scientists enamored with the new idea of experimental science

  • Scientific method was a novelty

  • Frame a hypothesis about how the world works

  • Hypothesis makes testable predictions

  • Run experiments to test these predictions

  • Accept, reject, or modify the hypothesis

  • Hooke later helped to establish the Royal Society of London

  • Became the Society’s Curator of Experiments in 1662

  • Gave a famous series of lectures in geology (1667-1668) to meetings of the Society, published the lectures in 1705

  • Hooke helped to establish many important ideas

  • Earth had no plastic faculty to make fossils

  • Fossils were organic remains

  • Organisms found as fossils had gone extinct

  • Species could change over time

  • Both Hooke and Steno were modern in one sense, primitive in another

  • Both were aware that their observations contradicted church doctrine (modern)

  • Both went to great lengths to explain how observed geological changes could be squeezed to fit church’s limited time frame (primitive)

  • Hooke, like Steno, was a devout Christian, also became more devout with age

  • Unlike Steno, Hooke never turned away from science, though his later lectures have many more references to Biblical events

  • Both Hooke and Steno maintained that the Earth was only ~6,000 years old

  • Conflict between science and religion in the 17th Century was not a war between science and religion as such

  • Rather, a struggle between two different approaches to science, Descartes vs. Newton

  • Descarte’s mechanistic philosophy kept God at arms length

  • God was the prime mover, created laws of the universe, then let nature take its course

  • Newton - laws of science were the divine blueprints of creation, expressions of the will of God, creator was actively involved

  • Battle lines between science and religion over the age of the Earth were hardened by the work of Thomas Burnet

  • Burnet was a geologist hailed in his day as one of the greatest thinkers of all time

  • Ranked with Newton, Descartes, Milton etc.

  • Burnet - Sacred Theory of the Earth (1681)

  • Strict fundamentalist approach to geology

  • Starts by assuming the Earth was created ~ 4,000 BC, dates biblical flood ~ 2400 BC

  • Predicted that the next biblical destruction will be a global wildfire

  • Burnet borrowed idea from Descartes that the Earth started as a burnt out star, cooling from the outside in

  • Shell of solid matter wrapped around a layer of ocean water

  • Original “smooth” Earth surface was Paradise

  • As the crust dried out it fragmented

  • Unleashed ocean waters onto the surface, leading to the Great Deluge

  • Modern Earth was ugly broken shell compared to earliest state

  • Problem confronted by Hooke and others was to explain how the Earth could have been shaped in so dramatic a fashion in a mere 6,000 years

  • Maybe through a series of catastrophes, like the Biblical flood

  • Hooke eventually went to great lengths to reconcile his geology with the Bible

  • Ransacked the Bible for catastrophes that might help explain modern geology

  • Legend of Atlantis was the only thing that came close to explaining the biblical flood

  • John Woodward (1665-1728) typifies the extreme British element in catastrophist geology

  • Natural History of the Earth (1695), heavily influenced by Steno

  • All fossil bearing strata was laid down at the time of the Deluge

  • Great flood churned everything into a great suspension

  • Fossils settled out after the flood according to their specific gravity

  • Modern creationists actually tried to test this in their ICR Technical Monograph Series!

  • Woodward’s theory was very influential

  • Interpreted fossils correctly as remains of once-living animals

  • Could accommodate presence of fossils in the rocks with divine plan

  • Inspired others to use fossil evidence as proof of the Deluge

  • Still bothered by the idea of extinction

  • Adopted the common notion of the day - world was mostly unexplored so who could say weird fossil creatures weren’t out there somewhere…

  • George-Louis LeClerc, later honored as Comte de Buffon, another pioneer in the search for the history of the Earth

  • Buffon (1707-1788) was appointed keeper of the Jardin du Roi under Louis XV

  • Asked to catalog the garden’s extensive natural history collection

  • Became intrigued with the idea of publishing a complete encyclopedia of the natural world

  • Managed to complete 35 of 50 volumes planned - Histoire Naturelle

  • Buffon believed life originated through spontaneous generation

  • Carried out a series of experiments to determine the time it took to cool balls of molten iron of various sizes

  • Buffon theorized that animals were formed from an internal mold

  • Each family of animals (dogs, cats, bears etc…) had diverged from a common ancestor (= modern)

  • The common ancestor had been specially created (= primitive)

  • If species were specially created, they must be perfect, by definition, so how could they change ??

  • Theory of Degeneration - new species were simply a degenerate version of the created species

  • Ancestral types were created, then wandered to different parts of the world

  • They experienced new climates, new conditions in different places

  • Invisible organic particles, peculiar to different places, gradually caused them to degenerate into a new species

  • Buffon’s theory had two very modern ideas:

  • Biogeography (geographical distribution) was important in understanding natural history

  • The environment can influence the basic nature of animals

  • Fifth volume - Epoque de la Nature (1778)

  • Described seven epochs in earth history

  • Planets were formed by a collision between a comet and the Sun

  • Ejected mass from the sun which later separated out into the planets

  • Still could not account for the history of the Earth in terms of overall Biblical time

  • Suggested that Earth’s original “softness” accelerated the pace of geological change

  • Later modified his views, Earth must be (gasp!) tens of thousands of years old

  • Estimated age of the Earth at ~ 100,000 years, origin of life ~ 35,000 years ago

  • Buffon thought that fossils might be organisms that were adapted to much greater heat

  • As Earth cooled, they went extinct

  • 18th Century - period of the Enlightenment

  • Intellectual climate encouraged more radical theories

  • Many of these theories were at odds with strict fundamentalist ideas

  • Buffon strongly criticized both Burnet and Woodward

  • Deluge was meant as a moral lesson, not a lesson in geology




  • Buffon saw no real conflict between science and religion

  • Creator was a rational being, therefore creation itself must be rational, orderly

  • If creation were rational, it could be understood

  • Science was the proper way to deal with proximate causes

  • OK for science to ask what

  • Religion was the proper way to deal with ultimate cause - God’s will

  • Not OK for science to ask why

  • Buffon thought the universe operated through a few simple laws of nature

  • Forces included motion, chemical reaction, heat, vital energy

  • Chemical reactions resulted from the attraction between small particles of matter

  • Life resulted from the attraction of small particles, through heat energy, to form organic compounds

  • Efforts of Steno, Hooke, Buffon etc. ultimately found an answer in the theory of catastrophism

  • Basic idea of catastrophism was that geological forces were not constant or uniform over time

  • These forces operated with greater intensity in the past

  • History of life was punctuated with catastrophes, like the biblical deluge

  • Idea of catastrophism became very popular

  • Provided a way to explain how the complex surface of the Earth could have been shaped in a relatively short period of time

  • Forces of nature operated with catastrophic intensity in Earth’s early history

  • Earth had more fiery energy in its early days, has been steadily losing that energy ever since

  • Modern forces not nearly as intense as prehistoric forces

  • Some catastrophists speculated that the divine plan behind nature was expressed through not one, but a series of special creations

  • As the Earth cooled, changed, the creator periodically wiped out the old creatures, replaced them with new creations more suited to the changed environment

  • Catastrophism provided a dogmatic way to explain the problem of extinction

  • If the creator were a perfect being, then by definition all of his creations would be perfect as well

  • How could a perfect being go extinct?

  • Not merely an attempt to reconcile science and religion

  • Most catastrophists were not religious zealots, out to prove the bible was factual by finding evidence of the great flood

  • Wanted to find a way to reconcile personal beliefs with scientific observations

  • As a scientific theory, catastrophism helped to explain some basic geological facts in a reasonable manner

  • Sharp discontinuities in rock layers, fossil sequences

  • Evidence of geological violence - glacial erratics etc.

  • In contrast with the school of catastrophism was the idea of uniformitarianism

  • Forces of nature were uniform, no different in the past than they are today

  • This implied a much more ancient history for the Earth, a long period of gradual geological change

  • First major supporter of uniformitarianism was the Scottish geologist James Hutton

  • Hutton’s Theory of the Earth was the first work of modern geology

  • Earth’s form could be explained by slow and gradual action of the same geological forces seen at work today

  • No need to invoke biblical catastrophes

  • Implied a very ancient origin for the Earth

  • James Hutton was born in 1726 in Edinburgh

  • Went through several career changes - tried business, lasted only a year as a legal apprentice

  • Went to med school, never established a regular practice

  • Inherited a farm, proved to be a successful farmer

  • First farmer in Scotland to use a two-horse plow

  • As a farmer, working outdoors, he became interested in geology

  • Retired from farming, moved back to Edinburgh, thriving intellectual community

  • Debated his theories with many great contemporaries - Adam Smith (Wealth of Nations), James Watt (steam engine)

  • Published Theory of the Earth in 1788, at the age of 62

  • Hutton claimed Earth’s rocks were formed by heat and compaction

  • The same heat forces rocks upward from the sea, following their deposition in orderly layers on the ocean floor

  • Used geographic descriptions from antiquity to help estimate how much the face of the Earth had changed since then

  • Earth must be extremely old, judging from modern rates of erosion

  • Hutton’s book was ignored

  • Made no attempt to reconcile geology with the biblical flood

  • Contradicted the prevailing theory of Neptunism

  • Hutton sought to explain Earth’s history as a divinely inspired steady state

  • Endless cycle of uplift and erosion was God’s plan to keep the planet habitable forever

  • Hutton’s ideas were popularized by John Playfair in Illustrations of the Huttonian Theory of the Earth (1802)

  • Preserved the basic outline of Hutton’s theory

  • Stripped away the religious overtones

  • Neptunists believed the Earth did not rise from the sea, rather that sea levels had steadily shrunk, gradually exposing land

  • Neptunists tried to estimate the age of the Earth by measuring the annual drop in sea level

  • Hutton’s theory supported the competing theory of vulcanism ( = Plutonism)

  • Volcanic forces due to the Earth’s inner heat were responsible for the emergence of land surface

  • Hutton saw no need to invoke a divine plan behind nature

  • Earth was simply a gigantic machine, powered by heat

  • Earth had undergone natural cycles of creation, destruction, with a uniformity of geological forces over time

  • Hutton never gave an estimate of the age of the Earth

  • His idea of cyclic change opened up the possibility that the Earth could be essentially infinite

  • Hutton’s work was swept up in the conservative backlash to the Enlightenment

  • Very intense debate arose in the late 18th, early 19th Century, over Earth history

  • Horrors of the French Revolution made many people nervous, fearful

  • Authorities felt that the soft moral climate, lack of piety, and “free thinking” had contributed to the French Revolution

  • Became gun shy about any new radical ideas (like Hutton’s), especially those with moral implications

  • Hutton was attacked for being impious, because his work completely ignored biblical geology

  • Hutton was devout, saw the cyclic nature of the Earth as a sign of divine benevolence, an eternity of self-regenerating creation

  • Hutton never denied special creation

  • Rather, he only claimed that we couldn’t determine when it had happened

  • “We find no vestige of a beginning - no prospect of an end”

  • Not the right time for new ideas...

  • Hutton’s work would be rediscovered and rehabilitated 40 years later, by a young geologist named Charles Lyell


Directory: ~bfleury -> historyoflife -> lectures
~bfleury -> In our last lecture, we looked at the ways that trade, travel, technology and agriculture can provide new habitats and new dispersal routes for microbes
lectures -> Dinosaurs 3 Several morphological features suggest dinosaurs relied on visual displays for communication, like modern animals
lectures -> Cells to Organisms 3 Eukaryotic cell was a giant leap forward in the early history of life
lectures -> Id is nothing new latest attempt to put a modern face on some very old ideas is old wine in new bottles…
lectures -> The mystery of life itself… We each spend our own lifetimes trying to answer that question in our own way
lectures -> The Discovery of Time
lectures -> Origin of Life 3 How could a system as complex as a living cell get started?
lectures -> Dinosaur Renaissance Most young boys (and many young girls!) play with dinosaurs


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