Paleontology - prelims

• Paleontology


  The study of the life of the past, is like a crime scene investigation - there are clues here and there, and the paleontologist can use these to understand something about an ancient plant or animal, or a whole fauna or flora, the animals or plants that lived together in one place at one time.
• Fossils


  physical remains of organisms or traces of their behavior preserved in the rock record
• Body fossils


  physical remains of organisms preserved in the rock record
• Trace fossils


  traces of behavior of organisms preserved in the rock record
• Origin, Different worlds, climate and biodiversity change, shape of evolution, extinction, dating rocks, biostratigraphy, paleoecology, paleogeography


  Reasons why we should study paleontology
• Sir Francis Bacon


  (1561-1626) He established the Induction method in science

  Argued that it was through patient accumulation that we can explain natural phenomena

  
  

  Science is achieved by skeptical and methodological approach where scientists avoid misleading themselves
• Deduction


  A series of observations point to an inevitable outcome.
• Karl Popper


  (1902-1994) He explained the way science works as the hypothetico-deductive method. He argued that in most of the natural sciences, proof is impossible. What scientists do is to set up hypotheses, statements about what may or may not be the case.
• Thomas Kuhn


  (1922-1996) Science shuttles between so-called times of normal and scientific revolution.

  Science doesn't evolve, it only has a paradigm remaining constant before going to a shift
• Speculation


  the forming of a theory or conjecture without firm evidence
• Hypothesis


  a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
• 1. Reconstruct the skeleton and muscles

  2. Work out the basic biology

  3. Colors and patterns, breeding habits, and noises.


  Levels of certainty in paleontology
• Early Greeks (e.g.) Herodotus and Xenophanes


  Recognized that some fossils were marine organisms and provided evidence for earlier positions of the oceans
• Roman and Medieval times


  Fossils were often interpreted as mystical objects in these times
• Plastic Force "Vis Plastica"


  Most fossils were recognized as looking like the remains of plants or animals, but they were said to have been produced by a...that operated within earth.
• Robert Plot


  Ammonites were formed by 2 salts shooting different ways which by thwarting one another make a helical figure was argued by whom?
• Beriger's Lying Stone


  Fossil specimens brought by collectors from the surrounding area but tumed out to be carved limestone into the outlines of shells, flowers, butterflies, and birds which had been paid by an academic rival.
• Leonardo da Vinci


  He used his observation of modern plants and animals, and of modern rivers and seas to explain the fossil sea shells found high in the Italian mountains. Argued that the sea had once covered these areas.
• Nicolaus Steno


  Demonstrated the true nature of Glossopetrae (glossopteris) by dissecting the head of a huge modern shark which showed that its teeth were identical to the fossils
• Robert Hooke


  Gave a detailed descriptions of fossils using a crude microscope to compare cellular structure of modern and fossil words, and the crystalline layers in the shell of a modern and a fossil mollusk. He also hinted the idea of extinction.
• William Hunter


  American Incognitum was quite different from modern elephants and from mammoths and was clearly an extinct animal, and a meat-eating one at that.
• Georges Cuvier


  Demonstrated the reality of extinction, sometimes called as the father of comparative anatomy where all organisms share common structures. After 1800s, he established the reality of extinction.
• 6000-8000


  Approximate age of the bible
• Progression


  Sequence from simple to complex organisms through time
• Charles Lyell


  Antiprogressionist, fossil record showed no evidence of long-term, one way change, but rather cycles of change.
• Jean-Baptiste Lamarck


  Explained the phenomenon of progressionism by a large scale evolutionary model, "Great Chain of Being" or the Scala Naturae. All organisms and extinct were linked in time by a unidirectional ladder leading from simplest at the bottom to most complex at the top.
• Charles Darwin


  Developed the theory of evolution by natural selection. Emphasized the idea of evolution by common descent, namely that all species today had evolved from other species in the past.
• On the Origin of Species (1859)


  The book that Charles Darwin published 21 years after the idea of natural selection
• 1. Micropaleontology - microscopic

  2. Paleobotany - plant fossils

  3. Palynology - pollen and spores

  4. Invertebrate paleontology - animals w/o backbone

  5. Vertebrate paleontology - animals w/ backbone

  6. Human paleontology - paleoanthropology; hominids

  7. Taphonomy - process of decay and fossilization

  8. Ichnology - tracks and traces

  9. Paleoecology - ancient climate and ecology

  Sub-disciplines of paleontology
• Rock Stratigraphy- stratigraphic context


  Essential framework; used to accurately locate fossil collections in both temporal and spatial frameworks
• Leonardo da Vinci's art - some 200 yrs before Steno


  Portrayed a clear sequence of laterally continuous, horizontal strata displaying the concept of superposition
• Giovanni Arduino


  Recognized 3 basically different rocks suites in the Italian part of the Alpine belt
• Lithostratigraphy


  Classification of bodies of rock based on the observable lithological properties of the strata and their relative stratigraphic positions
• a. Group - Two or more formation

  b. c.

  Formation - Primary unit

  Member - Named lithologic subdivision of a formation

  d.

  Bed - Distinctive layer in a member or formation

  e.

  Flow - Smallest distinctive layer in a volcanic sequence

  Lithostratigraphic Units
• Formation


  A rock unit that can be mapped and recognized across the country, irrespective of thickness, is the basic lithostratigraphic category. May comprise one or several related lithologies.
• Member


  More local lithologic development, usually part of a formation, a succession of contiguous formation, witho some common characteristics is often defined.
• Bed


  Lithologically distinct layer within a member or formation and is the smallest recognizable stratigraphi unit, usually not names, but may be in the case of a marker horizon.
• Fossil assemblages


  Groups of fossils found together in strata.
• William Smith


  A Canal Engineer, realized that different rock unites were characterized by distinctive groups of assemblages of fossils.
• Georges Cuvier and Alexandre

  Brongniart

  Ordered and correlated Tertiary strata in the Paris Basin using a series of terrestrial vertebrate faunas occurring in sequences, separated by supposed biological catastrophes.