CHAPTER 10 KEY TERMS
Family Tree
Biological Evolution
Theory of Evolution
Theory of Natural Selection
Mutation Theory
Mutation
Homologous Structures
Mutation-Selection Theory
Survival of the Fittest
Theory of acquired
characteristics
CHAPTER 10
BIOLOGICAL EVOLUTION
EVOLUTION
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THEORY OF EVOLUTION
• The theory that the universe began without God and has changed by
random processes into what we see today
• Biological Evolution
• The change of one kind of organism into another type of organism
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HISTORY
• Jean Baptiste Lamarck
• French biologist in the early 1800s
• First to propose the Theory of Acquired Characteristics
• Theory of Acquired Characteristics
• Physical changes caused by an organism’s environment can be passed on
to offspring
• Problem:
• Traits an organism acquires or loses does not affect the genetic material
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HISTORY
• Charles Darwin
• Naturalist who published “The Origin of Species by Means of Natural
Selection”
• Theory of Natural Selection
• The individuals in a species will compete with each other for the things
necessary for survival (food, shelter…)
• Some individuals can compete more effectively for needs
• These individuals will live and reproduce, passing on their characteristics
• Only those organisms best suited to survive will reproduce
• Survival of the fittest
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HISTORY
• De Vries
• Believed that only mutations could produce the genetic changes needed for
biological evolution
• Mutations only change the information already present
• Mutation alone cannot account for the change from one species to
another
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HISTORY
• Mutation-Selection Theory (sometimes called Neo-Darwinism)
• Combines De Vries’s mutation theory with Darwin’s natural selection theory
• 3 points
• Mutations supply new traits
• Organisms produce more offspring than can survive
• Selection allows only those with best traits to survive
• Problems:
• Mutations cannot explain development of complex structures that work
together
• Partially evolved structures would not work and be eliminated by natural
selection
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RECORD OF EVOLUTION
• According to evolutionists, the lining up of taxonomic groups should
show the path of evolution
• Evolutionary Family Tree
• A line-up of organisms showing the ancestry
of an organism
• The closer two organisms are on the tree, the
more related they are
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RECORD OF EVOLUTION
• Common Ancestor
• Secular scientists believe that all living organisms evolved from a common
ancestor
• Missing Links
• A “between” organism that would show how one organism evolved into
another
• Homologous Structures
• Structures or features that are similar in different types of organisms
• Attributed to common ancestry
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RECORD OF EVOLUTION
• Problems with homologous structures:
• Scientists pick and choose what are and aren’t homologous structures
• Genes for these “homologous structures” are different for different
organisms
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FOSSIL RECORD
• Evolutionary scientists, like Darwin, hoped the fossil record would prove
evolution was true
• They expected the lowest (oldest) layer of fossil record would contain
organisms found on bottom of family trees
• Also hoped to find missing links in fossil record
• Fossil record does not support evolution at all
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FOSSIL RECORD
• The fossil record does not support biological evolution for 3 reasons:
1. No complete and uninterrupted sequence of fossil layers
2. Missing links and common ancestors are not represented
3. Evidence supports idea that layers of fossils were laid down rapidly
• The biblical flood accounts for and explains these reasons
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ULTIMATE QUESTION
• How did it all start?
• Evolutionists believe in the idea of “spontaneous generation”
• Idea that life can come from nonliving materials
• Anything we believe about how life came to be is an act of faith
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