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Warm-up / EOC Prep- only write # 1
1. The process of DNA replication is necessary before a
cell —
A.makes a protein
B. codes for RNA molecules
C. divides into two cells D. modifies lysosome enzymes
2. In order to form recombinant DNA, scientists have
found a way to cut a DNA segment using an enzyme
named EcoRI. This enzyme cuts
DNA wherever the sequence
C-T-T-A-A-G occurs between the A
and the G base. Which of these
would result if EcoRI were used on
the DNA in the diagram to the right?
Agenda
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Warm-up
Notes
Darwin & Natural Selection Worksheet
Natural Selection Fish Lab
Whiteboards
Clean-up
Cool-down
Evolution is the core theme of
biology
“Nothing in biology makes sense except in the
light of evolution”
Theodosius Dobzhansky
Evolution Day 1
Darwin and the Theory of
Evolution
Historical
Background to
Darwin's Theory of
Evolution
• The theory of evolution has developed
through a lot of scientific observation
and experimentation and most scientists
today accept that evolution is the basis
for the diversity of life on Earth.
• Charles Darwin, who
later on developed the
idea of natural selection,
was born in England in
1809. He struggled in
school and his father
wanted him to be a
doctor or a minister.
•In 1831 Charles Darwin left on a 5 year
voyage on board the HMS Beagle to
survey the coast of South America.
•He stopped off in the Galapagos Islands
where the diversity of tortoises and birds
amazed him
•In 1836 he returned to England
• He specifically studied finches, a
type of bird with different sized
beaks on the islands. Each type of
beak was special for eating a
different type of food. The birds
adapted or changed so they could
eat their food. One bird could have
a long beak to get in holes to eat
insects, and another might have a
big beak to crush nuts.
Galapagos
Islands
Darwin’s Finches
Darwin saw variation
(difference) within species
on the different Islands, but
didn’t fully understand what
he saw till he returned to
England
• Another scientist, Jean Baptiste
Lamarck, believed that physical features
increased in size because of use or
decreased in size because of disuse.
His theories suggested that the
organism’s life determined what traits
got passed onto offspring.
• Giraffes
• No Evidence Ex: mice tails
• If a mouse has its tail cut-off, the mouse
will not have tailless offspring
• A heavy influence on Darwin’s theories
was the book Principles of Geology by
Charles Lyell, which explained that the
surface of the Earth changed slowly
over many years.
• Another influence was the work of
Thomas Malthus, who wrote that human
populations can increase faster than the
food supply.
•Geologists Hutton and Lyell
explained that the Earth was old,
and the economist Thomas
Malthus explained population
growth
• Populations breed rapidly, but
populations don’t grow
uncheckedMost organisms
in a population die without
breeding
• In 1859 Darwin published his book, On the
Origin of Species
• Darwin did not want to be criticized for
his ideas. However, he did not want to
lose credit for his ideas either, so when
a competing scientist, Alfred Russel
Wallace was about to come out with a
very similar idea Darwin had his ideas
along with Wallace’s presented at a
scientific meeting.
EVOLUTION
the process by
which modern
organisms have
descended from
ancient organisms.
EVOLUTION
the change over
time (in a gene pool
or set of genes)
FITNESS
the physical traits and
behaviors that enable
organisms to survive
and reproduce in their
environment
COMMON
DESCENT
all species have
common
ancestors
ADAPTATION
process that enables
organisms to become
better suited to their
environments
HOW DOES
ADAPTATION
WORK???
Over time?
In a single generation?
ADAPTATION
•TAKE PLACE OVER
LONG PERIODS OF
TIME!!!
•Only surviving (well
adapted) organisms pass
on their traits.
• The process by which new
species form is called
speciation. Geographic
isolation plays a large role in
speciation. Each environment
is different with different
pressures and challenges.
• Organisms adapt and change in
response to their specific
environment. If these
populations become different
enough they may even form
separate species-which cannot
interbreed.
REVIEW
• Who came up with the theory of natural
selection?
• Charles Darwin
• What was the name of his ship?
• HMS Beagle
• What islands did Darwin visit?
• Galapagos
• Change over time is called…
• Evolution
• What types of birds did he study and
what was different about them?
• Finches-their beaks
• All species have a common ancestor is
known as …
• Common descent
• Species: group of genetically similar
organisms that can interbreed, and
produce FERTILE offspring.
• Population: group of organisms of the
same species living in the same place
at the same time.
• Adaptation: changing of a given species
to become better suited to its
environment
• Natural selection: is process by which
populations change in response to their
environment
• Adaptation occurs as a result of
adaptation
• Complete the Darwin & Natural Selection
worksheet.
• Remember, if it’s FALSE, make it TRUE!
Natural Selection Fish Lab
• RULE # 1- DO NOT EAT THE FISH UNTIL
MS. GORNEY TELLS YOU TO!
• Each table needs
– One bag of fish
– One ocean (a paper plate)
Remember- hunt,
mate, and then
count
– BE NEAT WITH THE FISH! DO NOT DROP
THEM ON THE FLOOR! Pick them up if you do.
• Listen up, this will be graded!
Clean-up
• Dispose of the fish “properly.” Do not
leave ANY on the floor.
• Throw away the paper plates and bags.
• TURN YOUR FISH LAB PAPER WITH
THE QUESTIONS ANSWERED INTO
YOUR PERIOD’STRAY!
• Clean up this room!!
• That means…
• No paper or trash on the floor
• Chairs tucked under the desks
• Desks straight
• THANK YOU!!
Warm-Up / EOC Prep
1. Natural selection states that individuals
A with adaptive traits are more likely to survive
B on the bottom level of a hierarchy have the
greatest reproductive success
C demonstrating altruistic behavior are the ones with
the most mutations
D remain unchanged over a period of time
2. Which of the following best defines common descent?
A All organisms came from the same ancestor.
B All organisms have certain traits in common.
C All organisms descended from organisms that
have traits in common with them.
D All organisms have similar body parts and organs
in common.
Agenda
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Warm-Up
Notes
Evidence of Evolution Worksheet
Evolution Vocabulary Table
Whiteboards
Clean-up
Cool-Down
Evolution-Day 3
Age of the Earth and Evidence for
Evolution
Organic Soup Theory
• No oxygen in the air
• Organic molecules
accumulated
• A spark of lightning created
amino acids which over time
produced organisms
What was the first life like?
• Anaerobic organisms…why?
• Single celled prokaryotes
• Asexual Reproduction
• Heterotrophs…why?
What came next?
• Autotrophs…why?
• Probably used H2S instead
of H2O…why?
• Then they made the switch
to H2O…what happened?
• Sexual Reproduction--how
would this influence
evolution?
THE AGE OF
THE EARTH
How did scientists
figure out how old
the earth is?
2 ways to date the earth:
•Relative Dating—lower
levels of rock are older than
higher levels (not exact)
•Absolute Dating—the
actual age of a sample using
radiometric dating
RELATIVE DATING
RADIOMETRIC
DATING
RADIOMETRIC DATING
RADIOMETRIC DATING
If you start with 1000 atoms
of Uranium 238, how much
will be left after 4.5 billion
years? 500 atoms of U 238
RADIOMETRIC DATING
If you start with 1000 atoms
of Uranium 238, how much
will be left after 18 billion
years? 62.5 atoms of U 238
According to
scientists, the
earth is about
4.5 billion
years old.
THE
FOSSIL
RECORD
Where do we get
fossils from?
How do they
form?
PLACES TO FIND
FOSSILS:
• Ice
• Tar Pits / quicksand / bogs
• Amber / Sap
• Sedimentary Rock—
sediments fall on the living
material and turn it to rock
Fossils in
Amber
Are fossils a
perfect record of
evolution?
Why or why not?
No…
but they are a
convincing
window to the
past
Fossils are an incomplete
record of evolution because:
• Fossil record is incomplete.
Some organisms leave fossils,
but most do not
• Quality is variable. Some
are perfect, some are
not…missing details
FOSSIL RECORD
represents the preserved
collective history of the
earth’s organisms.
The fossil record shows
that changes in
organisms followed
changes on earth.
Example:
Shark teeth in Arizona
EVIDENCE
FOR
EVOLUTION
FROM LIVING
ORGANISMS
Present-Day Evidence
for Evolution
1. DNA Similarity
2. Biogeography
3. Homologous Structures
4. Vestigial Structures
5. Embryos
DNA
Similarity
Evidence for Evolution
DNA Comparisons between
Humans and other Species
Species
Human
Chimpanzee
Percent DNA Binding
100
98
Gibbon
Rhesus monkey
Tarsier
94
88
65
Lemur
Mouse
47
21
Chicken
10
Biogeography
Evidence for Evolution
BIOGEOGRAPHY
The study of patterns of
geographical distribution
of plants and animals
across Earth, and the
changes in those
distributions over time
Should species on these
islands look the same?
Placental Animals and their
Marsupial Counterparts
Placental
Wolf
Flying Squirrel
Marsupial
Tasmanian Wolf
Flying Phalanger
Mouse
Mole
Anteater
Bob Cat
Marsupial Mouse
Marsupial Mole
Numbat
Tasmanian Tiger Cat
Lemur
Spotted Cuscus
Biogeography
suggests that
species evolved
to fit their
environments
Homologous Structures
Evidence for Evolution
HOMOLOGOUS
STRUCTURES
parts in different
organisms that develop
from the same
anscestral body part
HOMOLOGOUS STRUCTURES
Vestigial Structures
Evidence for Evolution
VESTIGIAL
STRUCTURES
structures that have little
or no purpose in the
present, but did in the
past
Examples of
Vestigial
Structures
• Human appendix
• Tonsils
• Small vertebrae in humans
• Leg bones in snakes
EMBRYOS
Evidence for Evolution
EMBRYO
organisms in the
early stages of
development.
EMBRYOS
• Similar body structures
/ parts / organs
• Similar embryonic
development
Embryo Similarity
• What do you
notice about
the first row?
• What happens
as you move
down each
column?
• Clean up this room!!
• That means…
• No paper or trash on the floor
• Chairs tucked under the desks
• Desks straight
• THANK YOU!!
Warm-Up / EOC Prep
1. When Charles Darwin went to the Galapagos Islands
he saw various species of finches with different size
beaks. The finches got their different beaks as a result
of…
A passing on acquired characteristics
B adapting to different types of food in the separate
environments
C adapting to different types of weather
D wanting different beaks
2. In order for an organism to be biologically fit, it must:
A Survive
B Survive and Reproduce
C Be stronger than its competitors
D Be in the right spot at the right time
Agenda
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Warm-Up
Notes
Evolution Flip-flop
BIO BINGO
Clean-up
Evolution Day 2
Natural Selection and Evolution of
Populations
EVOLUTION
BY NATURAL
SELECTION
• Inherited variation exists within the
genes of every population or species.
This variation is the result of random
mutations and sexual reproduction.
• Variations provides the material for
natural selection
• In a particular environment, some
individuals of a population or species
are better suited to survive (survival of
the fittest)-as a result of their variationand they can then have more offspring
• These traits that help certain
individuals survive and
reproduce to spread in a
population over time, and
therefore a change in the
entire population is seenevolution occurs
• Each species has evolved and gathered
adaptations in response to its particular
environment.
• Certain forms of a trait become more
common in a population because more
individuals in the population carry the
alleles for these forms.
• Natural selection causes the frequency
of certain alleles in a population to
increase or decrease over time,
depending on if they are good
(favorable) for survival or bad (not
favorable for survival).
• If the trait is bad and does not help them
survive, the trait will become less
common (organisms will die, produce
less offspring, and therefore not pass on
the genes for the trait).
• What makes a successful variation or trait? One
that makes it more likely for you to:
• Get food
Not get eaten
• Have children
• Thermal conservation
NATURAL
SELECTION
The process in nature
where the most fit
organisms produce
more offspring
Darwin’s Theory of Natural
Selection
• The process of natural selection is
driven by four important points that are
true for all real populations:
1. All populations have genetic variation
2. The environment presents challenges
to successful reproduction (If you don’t
survive, you don’t pass on your genes
to the next generation)
Darwin’s Theory of Natural
Selection
3. Individuals tend to produce more
offspring than the environment can
support-which results in competition
• 4. Individuals that are better suited to
their environment and can cope with the
challenges presented by their
environment tend to leave more
offspring than those individuals that are
less suited to the environment
• Given time, natural selection will produce
different groups of organisms (speciation)
Example:
Giraffes show variation in
the length of their necks.
 Giraffes with longer
necks get better food,
have more babies
(greater fitness)
 Longer necks give birth to
longer necks
(trait is passed on in genes)
Results:
Over time,
average neck
length increases
Under other conditions,
over longer periods of
time, new species form
(e.g. the Okapi)
REVIEW
• The process in nature where the most fit
organisms produce more offspring is
called…
• Natural selection
• What makes a successful variation?
• Helps not get eaten, have babies, thermal
conservation, get food