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Evidence for Evolution
Story: Where did we come from?
Kansas State Board of
• 1999 this school board adopted new
statewide standards
• Missing was the Theory of Evolution
• In 2000 there was a backlash
• Some lost their jobs
• Theory of Evolution was added once
again to the curriculum
Kansas State Board of
Education - part 2
• In 2004 many ousted members were
• They adopted a different approach
• They mandated the teaching of ‘alternatives
to evolution’
• Other lawmakers in other regions of the US
have also interjected their views into the
teaching of evolution
Why the upheavals
• The root issue is the discussion of human existence
and origins
• Who are we?
• Where did we come from?
• Many religions include a key part about how humans
were designed by an intelligent supernatural being
• In contrast, evolutionary theory argues we
descended from ancient apes
• The courts have consistently upheld the constitution
and outlawed the teaching of religious beliefs at
• The Kansas State School Board argued that
the Theory of Evolution represents a religious
view too!
• One that rejects the actions of a higher power
• The same board voted to allow the teaching
of evolution provided the teachers discussed
‘gaps’ in the theory and offered alternative
explanations for these gaps
• Is this acceptable - both are a matter of faith
• Or is this a dangerous trend in US education?
What is evolution?
• Has two different meaning for biologists
– 1) A process
• Evolution means change - Biological evolution means
change in the characters of a population over
• These changes MUST occur at the genetic level
– Inherited characters (i.e. head lice example) = evolution
– Change in US women's dress size from 8 to 14 over the
past 50 years = no evolution
– Most people accept that this process occurs
• Aristotle was incorrect - he said species had never
What is evolution?
• Has two different meaning for biologists
– 2) A theory - The Theory of Evolution
• It is unfortunate that the word theory has a completely opposite
meaning to the nonscientist verses that formulated by scientists.
• It gives the notion of a ‘best guess’
– DEFINITION - All species present on Earth today are
descendants of a single common ancestor, and all species
represent the product of millions of years of microevolution
via natural selection and other modes of evolutionary
Common Descent
• Nearly every biologist accepts that modern
species evolved from ancient ones
• HOWEVER, recent polls of Americans
show that 50% of them do not believe that
modern species evolved from common
Common Descent is a fact!
• When Darwin published his book, most
Europeans believed that special creation was
fact - that God created all species during the 6
days of genesis
– As stated in the first book of the Bible - Genesis
– It states that little has changes since that time under 10,000 years ago
– The same basic belief is shared by Judaism & Islam
• Special Creation vs Common Descent
• Special creation involves a supernatural entity - this
makes it impossible to test by standard observation
involving the material universe
• The scientific method cannot be applied to a
supernatural entity
• One can test some assertions of special creation
– 10,000 years
– No change in species ever - the static model hypothesis
More than two hypothesis
• Other hypothesis - somewhere between
the two we have been considering exist
also • Transformation hypothesis
– Species can change over time
• Separate hypothesis
– Separate common ancestors which can
give rise to different species
All acceptable
• More polls indicated that American
• have about equal belief in all 4 of these
• as equally reasonable explanations for
the origin of biological diversity
Kansas Board and the citizen
• Most non-scientists believe that the
board was right in 1999
– It was right to outlaw the teaching of
evolution, to balance between the different
• Most non-scientists believe that the
board was right again in 2005
– Trying to be fair in allowing the
consideration of all other hypothesis
All is not equal
• Most scientists do not consider that the
different hypothesis are equal
• They base this view on all the current
testable evidence
• …lets consider this evidence with
respect to a very important debate…
Are humans really related to apes?
• Carl von Linne - (Carolus Linnaeus) Swedish doctor
• Classified all known life forms into biological
diversity based on form
• He proposed a two part name
• He also formulated a classification system
• Linnaeus was himself a believer in the
Creation hypothesis
Evidence from homology
• Similar observable features should
similar anatomical and genetic material
• This is what is being discovered…
• Comparative Anatomy
– The concept of homology
– Similarity of characteristics that has
resulted from common ancestry
• Most plausible explanation is
– Each species inherited the basic structure
from the same common ancestor
– The process that cause evolution led to
their unique modification in each group