Evolution Study Guide
Quiz dates: TH, 5/28 (B); F, 5/29 (A)
Darwin’s theory suggests that in
a species:
Charles Darwin (1809-1882)
• Voyaged around the
world 1831-1836
• Wrote On the Origin
of Species which
reveals his ideas on
Evolution by means
of Natural Selection
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•
•
•
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Jean Baptiste Lamarck
• 1774-1829
• Law of use/disuse
• Law of acquired
characteristics
Alfred Wallace (1823-1913)
• Studied the way
geography limited or
facilitated the
extension of species
range
• How ecology
influenced the
shaping of
adaptations
• In 1858, shared with
Darwin on the
Theory of Evolution
by means of Natural
Selection
Natural Selection Summarized:
•
There is a tendency
towards overproduction
Variation exists
Variations are inherited
Individuals survive in their
environments with varying
degrees of success
Best adapted, survive and
pass favorable variation on
to next generation
In time, great differences
arise, until a new species
evolved from an old
species
Hardy-Weinberg Equilibrium:
P2 + 2pq + q2=1; p+q=1
Population Genetics:
P2 = homozygous dominant portion of population
The Hardy–Weinberg principle states:
2pq = heterozygous dominant portion of population
 Both allele and genotype
frequencies in a population
remain constant or are in
equilibrium from generation
to generation unless…
 Disturbing influences happen
such as non-random mating,
mutations, selection, limited
population size, random
genetic drift and gene flow.
 Genetic equilibrium is a basic
principle of population
genetics.
q2= homozygous recessive portion of population
p represents the dominant allele
q represents the recessive allele
[Grab your reader’s attention with a great
quote from the document or use this space
to Be
emphasize
a key
point. To place
this text
able to solve
Hardy-Weinberg
problems:
box anywhere on the page, just drag it.]
Remember if the word problem is using the
words individual, genotype or phenotype
focus on the P2 + 2pq + q2=1 portion of the
equation
If problem begins by using the word allele
Start with the p+q=1 part of equation
Natural Selection can affect the
distributions of phenotypes in 3 ways:
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•
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Directional selection
Disruptive selection
Stabilizing selection
Vocabulary to review:
Directional Selection
See review slides on HW site:
When individuals at one end of the curve have
higher fitness than individuals in the middle or
at the other end.
Biological fitness
Coevolution
Adaptive radiation
Vestigial structures
Homologous structures
Disruptive Selection
When individuals at the upper and lower ends of the
curve have higher fitness than individuals near the middle.
Stabilizing Selection
When individuals at the upper and lower ends of the curve
have higher fitness than individuals near the middle.
Convergent evolution