On November 24, 1859, Charles Darwin published On the Origin of Species by Means of Natural Selection.

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CHAPTER 22 DESCENT WITH MODIFICATION A
DARWINIAN VIEW OF LIFE

• On November 24, 1859, Charles Darwin published On
  the Origin of Species by Means of Natural
  Selection.
• Two major points
• Todays organisms descended from ancestral
  species.
• ___________________ provided a mechanism for
  evolutionary change in populations.

Came to the conclusion that the Earth was _______
and constantly _______.
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• Darwins views were influenced by
• 1. Fossils in sedimentary rocks.

Fig. 22.2
2. A 5-year voyage around the world
Fig. 22.4
3. ________________ theory of ____________________
earth processes are constant over time
4.Jean Baptiste _________- 1809 publication of a
theory of evolution based on his observations of
fossil chronologies in the Natural History
Museum of Paris.
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The Origin of Species challenged a worldview that
had been accepted for centuries

• The Old Testament account suggests rapid
  creation, not evolution

• The Darwinian view of life has two main
  features.
• (1) The diverse forms of life have arisen by
  descent with modification from ancestral
  species.
• (2) The mechanism of modification has been
  natural selection working over enormous
  tracts of time.

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• This evolutionary tree of the elephant family is
  based on evidence from fossils.

Fig. 22.7
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Natural selection in easily observed

• _________________________ in insects
• _________________ resistance in humans

• 3TC-resistant strains of HIV become 100 of the
  population in just a few weeks.

• In each generation the percentage of resistant
  individuals increases.

• _________________ favors those characteristics in
  a variable population that fit the current, local
  environment.

Natural selection does not prove large-scale
evolution and speciation, only adaptation
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Evolution is inferred
What is the evidence for evolution?

• 1. Homologous ___________________
• For example, the forelimbs of human, cats,
  whales, and bats share the same skeletal
  elements, but different functions

Fig. 22.14
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• 2. _________________ in some creatures
• Example-some snake skeletons have vestiges of the
  pelvis and leg bones
• Fossil whales with vestigal legs and pelvis

3. ______________________
All vertebrates look the same as early embryos,
then changes are observed later.
4. All of life shares the same ________________
5. DNA sequences are more homologous in like
creatures than ________ ones
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6. The _________________ Different organisms
appear at distinct times in the fossil record
..But transition creatures are almost
non-existent

• 7. Isolated places have distinct populations
• There are numerous unique creatures on isolated
  islands- Australia, Galapagos islands,.
• Old World vs New World monkeys

How does one reconcile evolution with Genesis
account?
Many scholars reject evolution theory outright.
Others suggest vast periods of time between 1st
and 2nd days of Genesis creation- . Others
suggest God-directed evolution Theistic
evolution
Michael Behe- suggests that life cannot just
happen, but is irreducibly complex
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• Uri Miller experiment- Mix NH4, methane, water in
  intense heat and electrical current
• Observe simple macromolecules are formed
• Is this evidence for a pre-biotic soup forming
  resulting in an organism?

History suggests that our descendents will look
back at this generation and say they understood
so little