Download Candy Dish Selection: Author

Summer 2006 Workshop
in Biology and Multimedia
for High School Teachers
THEORY OF EVOLUTION
Beth Mick - LESSON PLAN
• DISCUSSION ON WHAT DOES THE WORD
EVOLUTION MEAN?
• LECTURE - PPT
• SPECIATION ANIMATION - 2006 LS-HHMI
•
Breeding Bunnies Activity
www.pbs.org/wgbh/evolution/educators/lessons/lesson4/act1notes.html
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Candy Dish Selection: Author: Carol Tang
http://www.ucmp.berkeley.edu/education/lessons/candy_dish.html
Investigating Natural Selection Activity -
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http://bob.nap.edu/html/evolution98/evol6-c.htm
• CLASS DISCUSSION ON VIRUS EVOLUTION TO
INCLUDE HIV
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
REFERENCES
• Biology: The Dynamics of Life; Glencoe 2004
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http://evolution.berkeley.edu/evolibrary/home.php
http://www.hhmi.org/biointeractive/evolution/index.html
http://www.accessexcellence.org/AE/AEPC/WWC/1995/
http://www.darwinday.org/englishL/life/beagle.html
http://www.pbs.org/wgbh/evolution/index.html
DR. LUE, LIFE SCIENCE-HHMI OUTREACH PPT.
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CHAP 15 – THE THEORY OF
EVOLUTION
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CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CHAP 15 – THE THEORY OF
EVOLUTION
•
•
•
•
•
CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
http://evolution.berkeley.edu/evolibrary/home.php
CHARLES DARWIN – 1809-1882
• ENGLISH
• TRAVELED AROUND THE WORLD ON THE
BEAGLE – FAMOUS IN THE GALAPAGOS
ISLANDS
• OBSERVED MANY SPECIES AND FOSSILS
• WHY DID SOME SPECIES SURVIVE WHILE
OTHERS BECAME EXTINCT?
• NATURAL SELECTION
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
http://evolution.berkeley.edu/evolibrary/home.php
http://evolution.berkeley.edu/evolibrary/home.php
www.darwinday.org/englishL/life/beagle.html
www.darwinday.org/englishL/life/beagle.ht
Used by permission of Darwin Day
Celebration (at DarwinDay.org), 2006
I have called this principle, by which
each slight variation, if useful, is preserved,
by the term Natural Selection.
—Charles Darwin from "The Origin of Species"
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CHAP 15 – THE THEORY OF
EVOLUTION
•
•
•
•
•
CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
EVIDENCE OF EVOLUTION
• STRUCTURAL ADAPTATIONS
resemblance of one organism to
– MIMICRY
another or to natural objects
– CAMOUFLAGE among which it lives that secures
it a selective advantage (as
protection from predation)
Protective coloring or another
feature that conceals an animal and
enables it to blend into its
surroundings.
http://evolution.berkeley.edu/evolibrary/home.php
http://science.howstuffworks.com/animal-camouflage2.htm
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
EVIDENCE OF EVOLUTION
• STRUCTURAL ADAPTATIONS
– MIMICRY
– CAMOUFLAGE
– MILLIONS OF YEARS
• PHYSIOLOGICAL ADAPTATIONS
– CHANGE IN A METABOLIC PROCESS
– WHAT DO YOU HEAR ABOUT IN THE NEWS
ABOUT SOME BACTERIA?
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
http://evolution.berkeley.edu/evolibrary/home.php
WHAT OTHER INDUSTRIES WOULD BE WORRIED ABOUT
RESISTANCE?
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
OTHER EVIDENCE OF EVOLUTION
• FOSSILS
• ANATOMY
– HOMOLOGOUS STRUCTURES
A state of similarity in
structure and
anatomical position but
not necessarily in
function between
different organisms
indicating a common
ancestry or
evolutionary origin
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
OTHER EVIDENCE OF EVOLUTION
• FOSSILS
• ANATOMY
– HOMOLOGOUS STRUCTURES
– ANALOGOUS STRUCTURES -it performs the same function
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
OTHER EVIDENCE OF EVOLUTION
• FOSSILS
• ANATOMY
– HOMOLOGOUS STRUCTURES
– ANALOGOUS STRUCTURES
– VESTIGIAL STRUCTURE refers to an organ or part (for example, the
human appendix) which is greatly reduced
– EMBRYOS
from the original ancestral form and is no
longer functional or is of reduced or altered
function.
WHAT IS ANOTHER EXAMPLE
OF VESTIGIAL STRUCTURES?
http://evolution.berkeley.edu/evolibrary/home.php
Vestigial structures provide a clue to the
evolutionary history of a species because
they are remnants of structures found in the
ancestral species.
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
OTHER EVIDENCE OF EVOLUTION
• FOSSILS
• ANATOMY
– HOMOLOGOUS STRUCTURES
– ANALOGOUS STRUCTURES
– VESTIGIAL STRUCTURE
– EMBRYOS
• BIOCHEMISTRY
– WHAT 2 THINGS?
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CHAP 15 – THE THEORY OF
EVOLUTION
•
•
•
•
•
CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
MECHANISMS FOR EVOLUTION
• DO POPULATIONS OR INDIVIDUALS EVOLVE?
• WHAT IS A GENE POOL the total number of genes of every
individual in an interbreeding population.
• HOW CAN THE GENE POOL CHANGE?
– MUTATION
– GENETIC DRIFT
– GENE FLOW
• WOULD THESE THINGS EFFECT A LARGE POPULATION
OR A SMALL POPULATION MORE?
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
ALL IMAGES: http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
Gene Pool
•Large
•high genetic diversity
•increased chances of biological fitness, and survival.
•Small
•low genetic diversity
•reduced chances of acquiring biological fitness, and increased possibility
of extinction
•Increases when mutation occurs and survives
•Decreases when the population size is significantly reduced
•e.g. famine, genetic disease, etc.
•Consequences when gene pool is small
•low fertility
•increased probability of acquiring genetic diseases and deformities
•Gives an idea of the number of genes, the variety of genes and the type of
genes existing in a population. It can be used to help determine gene
frequencies or the ratio between different types of genes in a population.
CHAP 15 – THE THEORY OF
EVOLUTION
•
•
•
•
•
CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
WHAT IS NATURAL SELECTION?
There is variation in traits.
For example, some beetles are green and
some are brown.
There is differential reproduction.
Since the environment can't support
unlimited population growth, not all individuals get to reproduce to their full
potential. In this example, green beetles tend to get eaten by birds and survive to
reproduce less often than brown beetles do.
There is heredity.
The surviving brown beetles have
brown baby beetles because this trait has a genetic basis.
End result:
The more advantageous trait, brown coloration, which allows the
beetle to have more offspring, becomes more common in the population. If this
process continues, eventually, all individuals in the population will be brown.
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CHAP 15 – THE THEORY OF
EVOLUTION
•
•
•
•
•
CHARLES DARWIN
EVIDENCE FOR EVOLUTION
MECHANISMS FOR EVOLUTION
NATURAL SELECTION
SPECIATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
WHAT IS SPECIATION?
• GEOGRAPHIC ISOLATION
• REPRODUCTIVE ISOLATION
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
WHAT IS SPECIATION?
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GEOGRAPHIC ISOLATION
REPRODUCTIVE ISOLATION
GRADUALISM
PUNCTUATED EQUILIBRIUM
The view that speciation
proceeds by
imperceptibly small,
cumulative steps over
long periods of time
rather than by abrupt,
major changes.
The theory that speciation occurs in
spurts of major genetic alterations
that punctuate long periods of little
change.
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
WHAT IS SPECIATION?
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GEOGRAPHIC ISOLATION
REPRODUCTIVE ISOLATION
GRADUALISM
PUNCTUATED EQUILIBRIUM
DIVERGENT EVOLUTION
– ADAPTIVE RADIATION
• CONVERGENT EVOLUTION
Organisms NOT closely related,
independently evolve similar traits
as a result of having to adapt to
similar environments or ecological
niches.
Evolution of a
number of
divergent species
from a common
ancestor, each
species becoming
adapted to occupy
a different
environment.
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
ADAPTIVE RADIATION – AN EXAMPLE
OF DIVERGENT EVOLUTION
http://www.vanderbilt.edu/AnS/english/Clayton/Galapago_finches.gif
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.
CONVERGENT EVOLUTION – WHAT IS AN
EXAMPLE?
http://evolution.berkeley.edu/evolibrary/home.php
Life Sciences-HHMI Outreach. Copyright 2006 President and Fellows of Harvard College.