Transcript File

1.
Give one example of
an adaptation and
explain why it is an
adaptation.
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3. Give an example
of geographic
isolation.
2.
Define evolution by
natural selection.
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4. How are
convergent and
divergent evolution
different?
 Catalyst (5 minutes)
 Unit 1 tracking/mastery slips (10 minutes)
 Speciation Beach Ball review (If time)
 Evidence of Evolution: Part 1 (20
minutes)
 ThinkTacToe (15 minutes)
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Homework:
 DBA #5: 9/29
 Honors: 9 weeks project due September
26th (THIS FRIDAY)
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Office hours tomorrow
Dojo review tomorrow
Lab Wednesday
Binder quiz this week ;)
6th period prize
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3 standards:
 Flow of Matter
 Population Graphing
 Human impact, succession, and biogeochemical
cycles combined
 Mastery levels/Tracker shading
 Process for grade recovery
What determines which organisms survive
and which do not?
 Do species ever change?
 How do scientists believe all of the species
that exist today were formed?
 What evidence is there to support
evolution?
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Crawlers from The Descent
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Humanoid
Cave-dwelling
Blind
No pigment
Moist skin
Incredible grip/climbing
abilities
 Bat-like ears
 Echolocation
 Carnivorous (raw meat)
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Are the crawlers a valid example of natural
selection?
What are their adaptations?
Are they favorable?
Is it believable?
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Cave dwelling
organisms
(Troglobites)
Instead of
“gaining” favorable
adaptations, they
lose adaptations
they no longer
need.
Divergent evolution
Speciation
Species
Convergent evolution
Geographic isolation
Reproductive isolation
Common ancestor
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SPI 3210.5.3 Recognize the relationships among
environmental change, genetic variation, natural
selection, and the emergence of a new species.
SWBAT identify the various forms of evidence
supporting evolution
 SWBAT explain how homologous structures
demonstrate common ancestry (relatedness) and
support evolutionary theory
 SWBAT identify examples of vestigial structures and
explain how vestigial structures provide evidence
supporting evolution
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Biology
Unit 2
Chapter 15, Section 2
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Evolution by natural selection is considered
the best scientific explanation for the
existence and diversity of life
 Scientific= testable & observable
 Keep in mind that science cannot prove or
explain everything, however
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Scientists use many forms of scientific
evidence in support of evolution
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We will focus on 4 forms of evidence
 Fossils
 Homologous structures
 Vestigial structures
 DNA and amino acid
sequencing
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Definition: Structures with similar composition,
placement and form but different functions
 Examples: Human arm, cat leg, horse leg, dolphin
flipper, and bat wing
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How do homologous structures provide
evidence in support of evolution?
 Homologous structures suggest that
organisms evolved from and share a
common ancestor because of their similar
bone structure and placement.
 They have different functions because each
species adapted to different environments
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What about structures with the same function?
Analogous structures are structures that
evolved in unrelated species, but have the
same function in different organisms
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Example: Bird wings vs. insect wings
They are found in unrelated species that only
use them for similar functions.
 These DO NOT provide evidence of evolution
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Mammals and insects both use their legs to
walk. However, their limbs are made of
different types of tissues and these
organisms are not closely related.
These are analogous structures
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Definition: Structures with little or no
known function in one organism but known
to have a significant function in other
organisms
 Examples: Snake pelvis, Kiwi wings, human
appendix
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How do vestigial structures provide
evidence in support of evolution?
 These structures suggest that a species
evolved because they are known to have
important functions in other organisms, so
they likely did in an ancestor of the species
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You must complete at least 5 THINK boxes.
Regular: You must complete one box in each
column. (i.e. 1 from T, 1 from H, 1 from I, etc.)
You may choose ANY boxes in the column.
(Honors: 3 of your boxes must be from the
“N” or “K” columns.)
On your own sheet of paper, write whatever
column and your answer in COMPLETE
SENTENCES
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Honors 9 weeks projects
Office hours
1. A flock of one species of birds
arrives on a group of sparsely
populated islands. With little or
no competition, different
species of birds evolve from the
original species. Each species is
adapted to a different available
food source. This is an example
of:
a. Divergent evolution
b. Convergent evolution
c. Dynamic equilibrium
d. Graduated equilibrium
2. What is the best evidence to
support the relationship of the
modern whale to the ancestor in
its evolutionary path?
a. The presence of a tail in the
ancestral whale
b. The observation that both
animals have teeth
c. The observation that both
animals live in the water
d. The presence of rudimentary hip
bones in the whale
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Catalyst: 5 minutes
Evidence of Evolution, part 2: 15 minutes
Manipulatives: 25 minutes
Homework:
Evidence for Evolution Homework
Unit 2 Study Guide due Monday
Honors 1st 9 weeks projects due FRIDAY
DBA #5: 9.29
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Mastery grades/Mastery packets
No grade slip?
Unit 2 test on MONDAY
Dojo review today
What determines which organisms survive
and which do not?
 Do species ever change?
 How do scientists believe all of the species
that exist today were formed?
 What evidence is there to support
evolution?


SPI 3210.5.3 Recognize the relationships among
environmental change, genetic variation, natural
selection, and the emergence of a new species.
SWBAT identify the various forms of evidence
supporting evolution
 SWBAT explain how homologous structures
demonstrate common ancestry (relatedness) and
support evolutionary theory
 SWBAT identify examples of vestigial structures and
explain how vestigial structures provide evidence
supporting evolution
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Biology
Unit 2
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http://science.nationalgeographic.com/scienc
e/prehistoric-world/prehistoric-time-line/
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Definition: Preserved
remains or imprints of
organisms that are found
in various levels of the
earth
 Bones, shells, imprints, etc.
 Older fossils are found
deeper in the earth; newer
fossils are found near the
earth’s surface
How does the fossil record provide evidence of
evolution?
 Many fossils are intermediate forms, whose
features show a transition from ancient species to
modern species
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 Features are in between those of ancient and modern
organisms
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This suggests that many species of organisms
have gradually changed over time
 Evolution
MODERN
OLDER
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Definition: Comparison of
all of the genes (genome)
found in different species
of organisms
 Example: Human vs.
chimpanzee DNA
 Comparisons can be of
actual “base pairs” (the
rungs of the DNA ladder) or
“protein sequences”
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DNA is the code for all
living things. Think of it
like blueprints.
The “code” is written in
sequences of base pairs.
These base pairs are
codes for amino acids.
Amino acids make up
proteins-the building
blocks of life.
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The instruction manual is
the blueprint for a Lego
kit.
The instruction manual is
written in an alphabet.
This instruction manual
tells you what Lego
pieces to put together.
These Lego pieces make
structures which make
the whole project.
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How does DNA sequencing provide
evidence of evolution?
 DNA sequencing shows many similarities in
the genome (all of the genes) of different
species
 Species with higher percentages of their DNA
(genome) in common are thought to be more
closely related and to share a common
ancestor
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Which two species
are most closely
related?
Species
DNA Sequence
Species 1
ACT GGT CCA
Species 2
ACT GGC TCA
Species 1 and 3
Species 3
ACT GTT CCA
Species
ACC GGT CTA
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Which two species are most closely related?
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Species 3 and 4
Species
DNA Sequence
Species 1
CCC GTG ATC TTA
Species 2
CTC GGG ATC TCA
Species 3
CCG TGG ATC TCA
Species 4
CCG TTG ATG TCA
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Which of the following is the best definition of
analogous structures?
A. Structures that evolved in unrelated species but
have the same function
B. Structures with little or no known function in one
species but an important function in other species
C. Structures with similar form and placement but
different functions
D. Structures left behind in various layers of the Earth
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Answer: A.
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Which of the following is the best definition of
homologous structures?
A. Structures that evolved in unrelated species but
have the same function
B. Structures with little or no known function in one
species but an important function in other species
C. Structures with similar form and placement but
different functions
D. Structures left behind in various layers of the Earth
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Answer: C.
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Ostriches have wings even though they do
not fly. What type of structures are the
ostrich wings?
Why do scientists suggest ostriches have
wings?
Answer: Vestigial structures; because they
were used (function) in an ancestor species
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The structures below are similar in form but
have different functions in different species.
What type of structure are they?
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Why are they different?
Answer: Homologous structures; the species
adapted to different environments
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The pictures below show fossils of related
species. The fossil on the right was found
deeper in the earth than the one on the left.
Which species is thought to be older?
Which species is thought to have evolved
more recently?
Sort the cards into 4 piles—one for
Homologous Structures, one for Analogous
Structures, one for Vestigial Structures, and
one for Fossils
 Check your piles with Ms. M when complete
 Then begin on your homework
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You need your Active Expression and your
notes.
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Have your homework on your desk.
 Catalyst (15 minutes)
 Evolution Stations (25 minutes)
 Closing (Remainder)
 Homework:
 Study for Unit 2 exam: Study guide
 Honors: 9 weeks project due
September 26th, FRIDAY
 DBA #5: 9/29
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Mastery packets
Honors article
 Define evolution.
 A. The emergence of a new species
from an existing species.
 B. The theorectical viewpoint on
how the Earth was created.
 C. Change in a population over time.
 D. A and C
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Define speciation.
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A. The emergence of a new organism.
B. The emergence of a new population of
organisms in a given area.
C. The emergence of a new species.
D. The emergence of individuals.
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Octopi are able to change color and
texture to blend in with their
environments. What type of
adaptation is this AND what
environmental factor contributes to
this adaptation?
Male peacocks with the most colorful tail
feathers are most likely to finding a mate.
Female peacocks choose mates based on
the color of their tail feathers. In reality, not
all males have bright, large tails, and this
was especially true a few thousand years
ago. Females are not likely to choose those
males as mates. Predict which tail feathers
the majority of the male peacock
population have today using the four
principles of natural selection. (Options:
BRIGHT or DULL)
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Define divergent evolution.
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A. the formation of a new, more similar
species
B. The development of a new population
C. The development of similar adaptations in
unrelated species
D. The development of multiple new species
from a common ancestor.
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Rainbow trout spawn
(reproduce) in the spring.
Brown trout spawn in the
fall. These two types of
organisms are not able to
mate and not the same
species. Is this an
example of geographic or
reproductive isolation?
A forest fire causes the permanent separation of a group of
deer from their native population, causing the small group to
interbreed only with one another. Over time, the group
becomes an entirely different species.
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Is this a result of geographic or reproductive
isolation?
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Ducks and platypuses both
have bills and webbed feet.
However, they are not
related. Is this an example of
convergent or divergent
evolution?
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Darwin studied finches on
the Galapagos Islands.
These birds had evolved
different beaks to eat the
different available food on
different islands.
Convergent or divergent
evolution?
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Give an example of two
homologous structures.
What determines which organisms survive
and which do not?
 Do species ever change?
 How do scientists believe all of the species
that exist today were formed?
 What evidence is there to support
evolution?
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How we rotate
Work
Expectations
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Unit 2 exam on Monday
Unit 2 study guide due on Monday
Honors 9 week projects