The Origin of Life

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The Origin of Life

• Chapter 18

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Overview of Origins

• Basic Worldviews
• Science and Its Limitations
• 5 Ways of Looking at Science and Faith
• Operational vs. Origin Science
• The Origin of Life
• Life from outer space?
• Prebiotic Synthesis?

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Christian Worldview

• The God of the Bible exists and the Bible is
  Gods revelation to humanity its purpose is to
  teach, rebuke, correct, and train us in righteous
  living so that we may become people of God
  prepared for a life of service- Richard Right
  (Biology Through the Eyes of Faith)

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Naturalistic Worldview

• The cosmos is all that is or ever was or ever
  will be- Carl Sagan

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A Common Worldview Among Scientists

• Naïve Positivism- science is the only body of
  knowledge that strictly follows empirical
  processes, and therefore supplies the only real
  human knowledge
• A belief that science holds the key to solving
  all of our problems science is elevated to
  scientism , a religion

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Worldview and the Cosmos

• Nature- is governed by natural laws and these
  operate on the basis of cause and effect to bring
  about all that happens in this natural realm.
  It is autonomous- it has independent status
• Creation- the entire material world and natural
  laws are dependent on Gods Existence

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3 Limitations of Science

• The study of the basic philosophies or ideologies
  of scientists is very difficult because they are
  rarely articulated. They largely consist of
  silent assumptions that are taken so completely
  for granted that they are never mentioned- Ernst
  Mayr
• Presuppositions- the uniformity of nature and the
  orderliness of the world are assumed

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3 Limitations of Science

• Proof- Science cannot provide proof of its
  results

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3 Limitations of Science

• Domain Limitations- science cannot give ultimate
  explanations for the origin and existence of the
  universe
• Science cannot comment on beauty, moral values,
  etc.

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Five Ways of Relating Science and Faith 1

• Difference in Essence- concerned with two
  distinct and separate realms- the natural and the
  supernatural
• Science and theology cannot even in principle
  come into conflict
• 1. Scaling the Secular City A Defense of
  Christianity by J.P. Moreland, Talbot School of
  Theology

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Complementarity View

• Science and theology describe the same phenomena
  at different levels of explanation and with their
  own vocabulary
• theology focuses on the why and who of a
  phenomenon and science focuses on the what and
  how
• evolution

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Weaknesses

• Tendency to blend naturalistic worldview into
  theology
• Miracles provide evidence for God and the
  supernatural (John 1025, 38 1411)
• If such miracles can be accounted for without
  gaps at a natural level, how could they provide
  evidence for the supernatural?

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Theology Foundational for Science

• Theology provides the metaphysical foundation
  for science and helps to ground the latter by
  explaining the necessary preconditions of
  science- J.P. Moreland

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Science Delimitative of Theology

• Science provides the boundaries within which
  theology must work. Theology can only do its
  work only after consulting science.-J.P. Moreland

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Interactive Approaches to the Same Reality

• Science and theology are interacting approaches
  to the same reality. Occasionally they make
  competing, interacting claims about the same
  reality in such a way that theology sometimes
  implies that gaps will exist in scientific
  accounts at those points where God intervened.-
  J.P. Moreland

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History of the Question, Where Does Life Come
From?

• Spontaneous Generation- the idea that new life
  could spontaneously arise on a daily basis
• Francesco Redi (1668)

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1864
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From Pasteur to Darwin

• We tell this story (of Pasteurs experiments) to
  beginning students of biology as though it
  represents a triumph of reason over mysticism.
  In fact, it is very nearly the opposite. The
  reasonable view was to believe in spontaneous
  generation the only alternative, to believe in a
  single, primary act of supernatural creation.
  There is no third position. George Wald
  (Harvard Biochemist)

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From Pasteur to Darwin

• The first theory places the question of the
  origin of life beyond the realm of scientific
  inquiry. It is a statement of faith in the power
  of a Supreme Being not subject to the laws of
  science. The second theory is also an act of
  faith. The act of faith consists in assuming
  that the scientific view of the origin of life is
  correct, without having concrete evidence to
  support that belief. Robert Jastrow (Astronomer)

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The Controversial Nature of Prebiotic Evolution

• A combination of geochemical evidence and
  laboratory experiment shows that such evolution
  is not only plausible, but almost undeniable
• The origin of life appears at the moment to be
  almost a miracle, so many are the conditions
  which would have had to have been satisfactory to
  get it going- Francis Crick

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Operational Science Vs. Origin Science

• Operational Science- controlled conditions,
  repeatability, ability to manipulate
• Makes hypotheses or models of unique events, much
  more speculative

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Two Major Naturalistic Views on the Origin of Life

• Panspermia- life was introduced on earth from
  outer space, perhaps by some higher intelligence
• Prebiotic Soup formed on earth with all major
  chemical components of life

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Naturalistic Proposed Stages in the development
of life

• Stage 1- early earth atmosphere with water, H2,
  CH4, CO2, CO, NH4, and N2 but no O2
• Stage 2-Electrical/UV energy generate amino
  acids, sugars, nucleic acids, and fatty acids
• Stage 3- Monomers polymerize into polymers

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Naturalistic Proposed Stages in the development
of life

• Stage 4-Polymers of nucleic acids, proteins,
  carbohydrates, and lipids form protocells
• Stage 5-True cells formed

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The Miller/Urey Experiment

• 5 amino acids formed, as well as precursors for
  adenine
• Similar experiments used to synthesize all five
  of the nitrogenous bases, and several sugars

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Criticisms of the Miller/Urey Experiment

• Methane and Ammonia were probably not present in
  the early atmosphere
• A reducing atmosphere is required for such
  experiments, while evidence has NOT established
  the absence of oxygen, contrary to the textbook
  claims
• Experimental Interference

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Organic Compounds from Meteors?

• Where did these come from?
• Estimations?

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From Monomers to Polymers

• Short RNA molecules can form in a test tube
• Polypeptides of up to 50 amino acids long can
  form spontaneously under certain conditions

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From Polymers to Cells

• Coacervates form from mixtures of polypeptides,
  nucleic acids, and polysaccharides
• Protenoid Microspheres are similar structures
  made from proteins alone
• Liposomes can form from a mixture of
  phospholipids and proteins

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Comments on These Protobionts

• IF these structures formed, they would contain
  random mixtures of random molecules, NOT
  concentrated mixtures of a particular useful
  enzyme
• Even if they had useful enzymes, they would not
  also contain the information for making those
  enzymes

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Genetic Systems

• Some RNA can self-replicate without proteins
• Some RNA molecules can act as enzymes
• We know that RNA is capable of storing
  information, and it might, perhaps, be able to
  replicate itself. But the hardest question to
  answer is how translation could have evolved.
  How a correlation between nucleotide sequences
  and amino acids sequences could have arisen
  remains a mystery

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History of Life on Earth

• Prokaryotic-Like Fossils are 3.5 billion years
  old- heterotrophs
• Stromatolite fossils are about 3 billion years
  old-autotrophs
• Eukaryotic cells appear about 1.7 billion years
  ago-heterotrophs and autotrophs

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How Photosynthesis Would Change the Earth

• Oxygen would build up in the atmosphere, causing
  the breakdown of the proposed primordial soup
• Cells could use oxygen to extract more energy
  from organic compounds, assuming they had
  mechanisms for dealing with the toxicity of oxygen

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Origins of Eukaryotes?

• Mitochondria and Chloroplasts derived from one
  cell engulfing another?
• No introns in mitochondrial and chloroplastic
  genes, ribosomes are similar to prokaryotic ones