Fossils: Pictures of the Past

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Fossils Pictures of the Past

• A tale of discoveries and hoaxes

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Figured Stones

• For centuries, people had noticed images of
  plants and animal remains in stones and wondered
  at them.
• In China, people sometimes found dragon bones
  (fossils bones of ancient animals) which were
  used to make medicine.
• Tongue stones (fossil sharks teeth) were known
  in Italy as curiosities.

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Fossil

• The term fossil in 16th and 17th century Europe
  referred to just about anything dug from the
  earth crystals, interesting mineral concretions,
  metal ores, and the figured stones that today
  are called fossils.

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Early European theories

• The rise of the Enlightenment brought new ideas
  about figured stones
• Did they grow from seeds or eggs trapped in
  rocks?
• Were they remains of victims of the Biblical
  flood?
• Were they organic at all?

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Early theorists

• Robert Hooke, John Ray, and Leonardo DaVinci all
  wrote about fossils, believing fossils to be the
  remains of once-living things.
• Others, such as Athanasius Kircher (17th century)
  attributed fossils such as tongue stones to a
  lapidifying virtue through the whole body of the
  geocosm.

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Leonardo da Vinci (1452-1519)

• In addition to his work as an artist, da Vinci
  was also a philosopher (scientist), inventor,
  and writer.
• Several of da Vincis observations on geology and
  fossils were remarkably modern.

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Horizontal Strata

• da Vinci observed horizontal rock strata and
  correlated layers on opposite sides of river
  valleys in and around the Alps.
• He correctly surmised that the layers had been
  laid down at the same time and that the rivers
  had sawn through them.

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River deposition

• da Vinci observed and recorded that rivers
  deposit large, angular rocks near their sources
  high in the mountains.
• Rocks that are transported by the rivers are worn
  down and rounded. Further downstream, deposited
  rocks grow smaller and smaller as the heaver
  rocks drop out of slower currents, until at the
  mouth of a river, there are only particles of
  silt, sand, or clay.

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Fossils and strata

• da Vinci observed clam fossils on mountaintops in
  the Alps, and was perhaps the first to propose
  that the rocks had once been sea floor.
• He also proposed that where layers bearing
  different fossils had been laid down at different
  times.

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Fossils as organic remains

• da Vinci observed that in living clams, the
  shells remain closed by a strong muscle, while in
  dead clams, the muscle relaxes and quickly
  decays, allowing the shells to fall open and
  disarticulate.
• From this observation, he proposed that clam
  fossils with closed shells were the remains of
  clams that had been trapped alive in silt.

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Steno (Niels Stensen, 1638-1686)

• Danish anatomist, studied medicine in the
  Netherlands and France.
• Came to Florence at the request of the Duke of
  Tuscany to run a hospital and continue his
  research.

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Steno and the Shark

• 1666 Fishermen in Livorno, Italy, caught a giant
  shark. The local duke had it shipped to Steno for
  study.
• Steno noticed similarities between the sharks
  teeth and tongue stones that were well known at
  the time.

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Stenos leap

• Like some others of his time, Steno thought that
  sharks teeth could be organic remains.
• However, Steno took it one step further, saying
  that the fossils that looked like sharks teeth
  really were sharks teeth, and were the remains
  of once-living sharks.

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Corpuscle Theory of Matter

• Steno used the Corpuscle Theory of Matter to
  explain the transformation of sharks teeth into
  tongue stones.
• Naturalists of the day hypothesized that matter
  was made of corpuscles (essentially molecules).
  Steno suggested that the corpuscles of the teeth
  had been gradually replaced by corpuscles of
  stone as the teeth sat in the rocks.

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But how did they get there?

• The obvious question, then, was how did sharks
  teeth end up in rocks on dry land?
• Stenos Principle of Original Horizontality
  Rocks once existed in a fluid state. Rock strata
  are formed when particles in a flud such as water
  fell to the bottom of the body of water, leaving
  horizontal layers. Later disturbances may alter
  the horizontality.

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Law of Superposition

• Steno reasoned that if rocks were deposited in
  layers, animal and plant remains could be trapped
  in those layers. Later disturbances could push
  rock layers above the waters surface.
• The oldest fossils should be found in the lowest
  layers. Younger fossils would be found in younger
  layers.

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Johann Beringer (d. 1740)

• Dr. Johann Bartholomew Adam Beringer, professor
  of Medicine in Würtzburg, lectured widely on
  fossils.
• Some, he stated, could be the remains of
  once-living organisms. Most, he thought, were the
  handiwork of God.
• Beringers arrogance may have been the impetus
  for one of the best-known fossil hoaxes in
  history.

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The Figured Stones of Würtzburg

• In 1726, Beringer published Lithographia
  Wirceburgensis, a catalog of fossils he and his
  assistants had unearthed near his home.
• God, the founder of Nature, would fill our minds
  with His praises and perfections radiating from
  these wondrous effects, so that, when forgetful
  men grow silent, these mute stones might speak
  with the eloquence of their figures.

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The Figured Stones of Würtzburg
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Figured stones?

• Some critics who examined the stones were quick
  to point out that they bore the marks of a
  chisel.
• Beringers response ...the figures..are so
  exactly fitted to the dimensions of the stones,
  that one would swear that they are the work of a
  very meticulous sculptor... and seem to bear
  unmistakable indications of the sculptors
  knife... One would swear that he discerned in
  many of them the strokes of a knife gone awry,
  and superfluous gouges in several directions.
  Beringer believed the sculptor was God, and the
  stones showed that God was practicing His skills.

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More stones

• Some figured stones even bore Hebrew letters,
  spelling out the name of God.
• Beringer took these as possible signs that the
  stones were the work of the Creator, but also
  suggested they could be sports of nature formed
  by the plastic power of the earth, or that some
  that resembled living things might grow from
  trapped seeds or eggs.

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But whose hand?

• Two of Beringers detractors, Ignatz Roderick and
  Georg von Eckart, admitted to carving and
  planting the stones themselves.
• Beringer at first accused the men of professional
  jealousy, but a public trial revealed that the
  men had committed the hoax.
• Beringer offered to buy back copies of his book
  that had been sold. However, after his death, his
  publisher brought out a second edition for the
  curious and those with a sense of humor.

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Discussion

• Consider the century in which Beringer lived, and
  views of fossils at the time. Why was he so quick
  to believe the stones were real, and willing to
  support a supernatural explanation for the
  stones?
• In Beringers work, he proposed a classification
  scheme, asked questions, posed multiple
  hypotheses about the origin of the stones, and
  invited discussion. In this, how did the quality
  of his work compare to that of Steno and da Vinci?