Download Theory of Evolution Notes

Theory of Evolution
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Evolution: The process of ____________________________________________.
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Specifically, a change in the ____________________ of a ____________ or ________________ in a
population over ____________________.
Charles Darwin
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__________________ of _____________________.
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Proposed a ______________________ for evolution, _________________ _____________________.
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Darwin went on a ______________ _______________ around the world on the ship, the _________
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____________________.
o As the ship’s naturalist, he made observations of organisms in South America and the Galapagos
Islands
Wrote a book, “______________________________________________________.”
Natural Selection
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Natural Selection: Organisms that are best _____________________ to an environment
__________________ and ________________________ more than others.
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Darwin’s Theory of _________________ ___________________ occurs in four steps:
1. ____________________________
2. ____________________________
3. ____________________________
4. ____________________________
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1. Overproduction
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Each species produces ___________________ offspring that can _____________________
2. Variation
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Each _________________________ has a unique ___________________________ of
________________ ___________________.
o Adaptation: an __________________ ___________________ that increases an organism’s
_____________________ of __________________________.
Why is Variation Important?
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Because the environment _________________________.
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The more variation ___________________ a species, the more likely it will
_____________________.
o EX: If everyone is the __________________, they are all ________________________ to
the same environmental __________________ or _____________________.
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The more variation of ________________ of species in a habitat, the more likely at least
some will ____________________________.
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o EX: ________________________ replaced by _____________________________.
3. Competition
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Individuals __________________________ for limited ________________________________:
o Food, water, space, mates
Natural selection occurs through “______________________________________________________.”
o Fitness: the ability to _____________________ and _________________________.
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Not all individuals survive to _________________________________.
4. Selection
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The individuals with the ______________ ______________ / __________________________ will
________________________ and have the opportunity to _______________ _____________ it’s traits
to offspring.
o Natural selection acts on the _________________________ (physical appearance), not the
________________________________ (genetic makeup)
o Ex: When a predator finds its prey, it is due to the prey’s _________________________
______________________________, like color or slow speed, not the alleles (BB, Bb)
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Individuals with traits that are not well suited to their environment either ______________ or leave few
offspring.
Evolution occurs when good traits build up in a population over __________________
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__________________________ and bad traits are _________________________ by the ____________
of the individuals.
Peppered Moth
Descent with Modification
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Descent with Modification – each living species has ______________________, with changes, from
other species __________________ ________________________.
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Common Descent – all living organisms are _________________________ to one another
Evidence for Evolution:
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Fossil Record
Homologous Body Structures
Vestigial Organs
Embryology
Biochemical Evidence
The Fossil Record
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Fossils: a record of the __________________ of ________________ on _________________.
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Archaeopteryx
Missing link between reptiles and birds
Homologous Body Structures
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Homologous Body Structures: __________________ ____________________ in different types of
_____________________ because of _____________________ ancestor.
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Vestigial Organs
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Vestigial Organs: “_______________________” traces of evolution that serve _______
_______________________.
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Embryology
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Embryology: embryos of all vertebrates are very _______________________ early on
Biochemical Evidence
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Biochemistry: ____________ with more similar sequences suggest species are ________________
closely _________________________.
o EX: ______________________ and _______________________________ share more
than _______________ of ________________________ DNA sequences.
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