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EVOLUTION
 Definition:
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Change over time
EVOLUTION
 Examples
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of evolution:
Cosmology- The origin and continuing
development of the universe
Chemistry- the change in macromolecules;
proteins, CHO, nucleic acids, lipids
Astronomy- dynamic orbits of various celestial
bodies
Geology- plate tectonics, volcanism, erosion,
and sedimentation
Evolution
 Examples,
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cont..
Meteorology- ice ages, global warming
Oceanography- El Nino, southern oscillation,
salinity
Anthropology/ sociology- morality, rites of
passage, caste systems
Politics- socialism, capitalism, totalitarianism
Religion- indulgences, burial of dead,
marriages, devotional offerings
Biology- emergence, modification, extinction
BIOLOGICAL EVOLUTION
 Definition:
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An inheritable change in a species over time,
usually as a result of natural selection
The successive changes in allele composition
and allele frequency in a population as
regulated by mutation, genetic drift, gene flow,
and selection pressure
Species: a group of interbreeding individuals
capable of producing fertile offspring (cannot
be used to define bacterial species)
BIOLOGICAL EVOLUTION
 Population
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vs Gene pool:
Population: a group of individuals of the same
species living in the same place at the same
time and potentially capable of interbreeding.
Gene pool: the total diversity of genes present
in a population at any given time.
Evolution
 Darwin…who
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was he?
Born in Shrewsbury, England
A naturalist
5 year journey on the Beagle exploring natural
history
Spent 20 years gathering evidence to support
his theory of evolution
Published findings in 1859
Evolution
Who and what influenced Darwin’s ideas?
Lamarck: Evolution through acquired
characteristics
Henslow: Established Darwin’s credibility in
the scientific community
Lyell: Wrote Principles of Geology, which
presented the idea that present-day
geological processes can explain the
history of the earth.
Evolution
Malthus: Human populations are able to
increase faster than the food supply. They
do not grow unchecked due to war, famine
and disease. Darwin applied this to
populations kept low due to a struggle for
existence, where only the strong survive.
This idea helped form the theory of Natural
Selection
Evolution
Wallace: Wrote a paper describing evolution
by natural selection, independent and
unknowing of Darwin’s research.
Asked Darwin for help, and Darwin rushed
to have his own paper published first.
Evolution
DARWINS IDEAS:
1. Inherited variation exists within the genes of
every species
2. Some individuals are better suited to survive
and have more offspring
3. Traits that enable organisms to survive and
reproduce spread in that population
4. Evidence from fossils and other sources that
living species evolved from extinct organisms.
Evolution
Evolution