Evolution

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Evolution
vs.
Intelligent Design
By Rian Pfund and Amy Wu
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To Jumpstart Your Brains This Morning
Discussion
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The Basics

• The view of evolution as change is accepted by
  all scientists. The question is not, has there
  been change, but what has caused the change?
• Darwin Evolution, Neo-Darwinian Synthesis,
  Chemical Evolution, Theistic Evolution,
  Intelligent Design
• Biological evolution ... is change in the
  properties of populations of organisms that
  transcend the lifetime of a single individual.
  Biological evolution may be slight or
  substantial - Douglas J. Futuyma in Evolutionary
  Biology

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A Brief History of the Evolutionary Theory

• Aristotle All life-forms are arranged on a
  ladder of increasing complexity. The species are
  permanent and do not evolve.
• Georges Cuvier (d. 1832) Believed catastrophes
  caused changes in the organisms on earth,
  strongly opposed evolution.
• James Hutton Theory of gradualism (1795), earth
  was molded by slow, gradual change.

• Charles Lyell Similar to Huttons beliefs, also
  believed earth was much older than 6,000 years,
  as thought by early theologians.
• Jean-Baptiste Lamarck Also developed a (now
  discredited) theory of evolution in 1809, based
  on the idea of inheritance of acquired
  characteristics.
• Alfred Wallace Naturalist, published an essay on
  natural selection right before Darwin, titled "On
  the Tendency of Varieties to Depart Indefinitely
  from the Original Type."
• Ernst Mayr Leading modern evolutionist

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Last but Not Least
Charles Darwin

• 1809-1882
• Left England at age 22 (1831-1836) on the HMS
  Beagle to visit the Galapogos Islands, South
  America, Africa, and Australia.
• Finished developing his Theory of Natural
  Selection to explain how populations evolve in
  the early 1840s, but did not publish them.
• Spurred by Wallaces paper, he published On the
  Origins of the Species in 1859.
• Immediate impact on religious thought.

I have called this principle, by which each
slight variation, if useful, is preserved, by the
term Natural Selection. - Darwin
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Principles of Natural Selection

• Populations tend to grow exponentially
  (overpopulate), to exceed their resources.
• Overpopulation results in competition and a
  struggle for existence.
• There is variation and an unequal ability of
  individuals to survive and reproduce in all
  populations. Darwin could not explain the origin
  of variation. Gregor Mendels theory of genetics
  (1865) could have explained them, but the theory
  was not yet understood.
• The fittest individuals survive and pass on their
  traits to offspring.
• Evolution occurs as advantageous traits
  accumulate in the population.

http//evolution.berkeley.edu/evosite/misconceps/i
mages/misconceptions_beavers.gif
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How the Giraffe Got Its Long Neck
Lamarcks Theory

• Long neck developed because giraffes eat the
  leaves of tall acacia trees. The giraffes
  stretched their necks and passed the acquired
  trait of an elongated neck to their offspring.
  This was a widely accepted theory in the early
  19th century.

Darwins Theory

• Early giraffes had short necks, although neck
  length varied from individual to individual. As
  the population of animals competing for the same
  food (leaves) increased, the taller giraffes had
  a better chance of survival. Over time, the
  proportion of long necks increased until giraffes
  were all long-necked.

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Types of Selection
Altering the frequency of inherited traits in a
population
Stabilizing
Sexual
Eliminates extremes and favors more common
intermediate forms. Weeds out mutants.
Directional
Based on variation in secondary sexual
characteristics for competing for and attracting
mates (horns, strength, size, color, etc.).
When one phenotype replaces another in the gene
pool, caused by changing environmental
conditions. Includes industrial melanism (i.e.
peppered moths), antibiotic resistance
(bacteria), and insecticide resistance (insects)
Diversifying
Increases extreme types at the expense of
intermediate forms. Can cause balanced
polymorphism, which can lead to two new species.
Artificial
Humans breed plants and animals seeking those
with desired traits as breeding stock.
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Sources of Variation

• Much variation is hidden in every gene pool, and
  can be expressed by selective pressures. The
  following are such sources
• Balanced Polymorphism 2 phenotypically
  distinct forms of a trait in a single population.
• Mutation provides new alleles to the gene pool
• Sexual Reproduction Shuffling of alleles during
  meiosis and fertilization
• Outbreeding tendency of species not to inbreed
• Heterozygote Superiority hybrid has greater
  survival rate
• Frequency-Dependent Selection decreased more
  common phenotypes
• Evolutionary Neutral Traits some variation have
  no selective value, scientists do not understand
  where they evolved from

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Evolution of Man
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Patterns of Evolution

• Divergent Evolution isolated population
• Convergent Evolution unrelated species occupy
  same environment
• Parallel Evolution two related species
• Coevolution predator/prey relationships
• Adaptive Radiation numerous species from common
  ancestor

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Modern Theory of Macroevolution

• Gradualism
• Organisms descend from a common ancestor
  gradually.
• Large changes occur through many small ones,
  thus fossils should exists at every stage of
  evolution. HOWEVER, transitional forms are
  rarely found.
• Punctuated Equilibrium
• Developed by Stephen Gould, Miles Eldridge, and
  Erst Mayr.
• Proposes that new species appear suddenly after
  long periods of stasis.
• New species changes most as it sprouts from
  parent species, then changes little from then on.
• "rapidly evolving peripherally isolated
  populations may be the place of origin of many
  evolutionary novelties. Their isolation and
  comparatively small size may explain phenomena of
  rapid evolution and lack of documentation in the
  fossil record, hitherto puzzling to the
  palaeontologist" Ernst Mayr

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ID An Overview

• Chance and natural laws are not enough to create
  life
• Some other mind or form of intelligence had
  manipulated power and energy to create life
• Thus life was created by a combination of laws,
  chance, and design
• ID does not look to explain who created life, or
  why they created it.
• ID does not deny evolution took place. It simply
  states that the Darwinian theory of evolution is
  not sufficient to account for the diversity of
  life

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Another Creation Theory?

• No! Creation science seeks to validate a literal
  interpretation of creation, as explained in the
  book of Genesis in the Bible.
• It is unconstitutional to teach this in schools,
  because it promotes certain religious beliefs.
• ID does not arise from any religious text
• Does not seek validation of any religious
  scriptures

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How do we detect design?

• Walking down a country road and see a stone.
• You would conclude it is formed by natural
  processes
• You see a watch
• You would assume it was formed by an intelligent
  source
• Unlike the stone the watch is made up of multiple
  tiny interlocking parts all working together for
  one purpose to tell time.
• Unfortunately just knowing is not a
  step-by-step scientific process.

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Design test!!!

• William Dembski has come up with a
  design-detection filter.
• First there are only three explanatory causes for
  an event pattern or object
• Chance
• Natural laws (necessity)
• Design
• Biological evolution states that only natural
  laws and chance created life
• Intelligent design states all three played a part
  in lifes origin.

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The Four Step Test

• 1) Does the pattern in question have a purpose,
  which is independent from the elements that make
  up the pattern?
• 2) Can the pattern be explained by a law or
  regularity?
• A salt crystal is formed because positively
  charged sodium ions are attracted to negatively
  charged chlorine ions
• A rivers course is directed by gravity and the
  presence of matter (rocks, trees, etc.)
• 3) Did the pattern occur by chance?
• The chance of spelling design by randomly
  pulling 26 scrabble tiles out of a bag is 1 in
  108.5
• Statistically speaking, an event having a 1 in
  10150 of occurring is virtually impossible
• 4) If not then the pattern must have been
  designed
• This means it was conceived by an intelligent
  mind, and brought into existence for a purpose,
  by manipulating energy.

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Examples!

• In the movie Contact, researchers find a pattern
  of beeps and pauses beating out the first twenty
  five prime numbers from 2 to 101. Upon hearing
  this they cry Eureka! We made contact! How did
  they know?
• 1) Does the pattern have a message, which
  different from the elements which comprise it
• 2) Is the sequence the result of any physical
  laws?
• 3) Could this be produced by chance?
• The probability of this pattern occurring is 1 in
  10338, vastly smaller than 10150.
• 4) Then it was created by an intelligent mind

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Looking at DNA

• Do biological events fit the design-detection
  filter? Lets look at DNA!
• 1) Does DNA have a purpose?
• Yes, it provides instructions for making proteins
  and molecules.
• 2) Is the sequence determined by physical laws?
• No, there is no law which determines the sequence
  of the DNA, although there are laws which account
  for the DNA being held together.
• 3) Could this happen by chance?
• The first cell would have needed 300 genes to
  function. The probability of constructing one
  gene, which codes for a 100 amino acid chain is 1
  in 10190
• 4) Then is must have been designed

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Evidence!

• Irreducible complexity
• Biochemist Michael Behe
• This describes a system in which all the parts
  are interdependent, and the removal of one part
  would cause the entire organism to cease
  functioning.
• Example Bacterial Flagellum
• Need at least forty interlocking movable proteins
  to function properly
• Removal of any one of these would cause the
  flagellum to cease functioning
• Contradicts evolution, which is a process of slow
  modifications over time.
• All proteins had to be present together at the
  same time for the flagellum to function, and
  therefore could not have slowly changed and

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More Evidence!

• Fossil evidence (Evolutionary gaps)
• Fossil evidence shows that life appeared on earth
  almost immediately after the temperature became
  habitable for life.
• There was no gradual evolution, as the Darwinian
  theory suggests.
• Another gap in the fossils took place during the
  Cambrian explosion, when over 40 unique new
  forms of life spontaneously appeared.

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Oh look! Even more evidence!

• Probability
• The probability of the construction of DNA, (not
  to mention all the other functioning
  biomechanisms) is virtually impossible
• Scientists postulate that the probability of life
  coming into existance is 1 in 1040000.

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Discussion

• Now that you know more about the two theories,
  discuss

Where did we come from?

• Does Darwinism or Intelligent Design seem more
  likely?

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References

• Allen, Christopher. Life With Alacrity. 16
  Aug. 2004. http//www.lifewithalacrity.com/.
• Campbell, Neil A. Biology. California
  Benjamin/Cummings Publishing Co. Inc., 1993.
• Mayr, Ernst. Speciational Evolution or
  Punctuated Equilibrium. 1992. http//www.stephe
  njaygould.org/library/mayr_punctuated.html.
• Moran, Laurence. What is Evolution. 22 Jan.
  1993, http//www.talkorigins.org/faqs/evolution-
  definition.html.
• Nagel, Thomas. Concrete Poetry. 20 Feb. 2004.
  http//jdc concrete.com/HISTORY.HTM.
• The Origin of Life and Evolution of the Cosmos.
  2004. http//www.originoflife.org.uk/.
• Picture of Charles Darwin, http//www.bio.miami.e
  du/dana/160/darwin.jpg.
• Population Genetics. 28 Apr. 2005.
  http//sps.k12.ar.us/massengale/population_genet
  ics_notesbi.htm.
• William S. Harris, PhD and John H. Calvert, JD
  Intelligent Design The Scientific Alternative
  to Evolution (National Catholic Bioethics
  Quarterly, Autumn 2003) http//www.intelligentdes
  ignnetwork.org/NCBQ3_3HarrisCalvert.pdf