Download Name Block ______ Unit 8 Evolution Biology 1 I. A Historic Voyage

Name _____________________________________________________
Block ________
Unit 8 Evolution
Biology 1
I. A Historic Voyage
A. Charles Darwin
1. 1831: Traveled on a boat named _________________________________
2. Places Darwin visited:
a. ____________________________ d. ____________________________
b. ____________________________ e. ____________________________
c. ____________________________
f. ____________________________
3. Things Darwin observed:
a. ________________________
b. __________________________
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B. The Galapagos Islands
1. Darwin studied one animal very much: ________________________________
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C. Tortoise Observations (page 371)
1. There are 3 different islands that Darwin visited
a. ___________________
b. _______________________
c. ______________________
2. Draw each tortoise
a.
b.
c.
3. Where does each tortoise find food?
a. ___________________
b. _______________________
c. ______________________
D. Darwin’s Questions
1. Why are the tortoise’s ______________________________?
2. Were the tortoise’s always _______________________?
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II. Darwin’s Theory
A. Living things can have many _________________________
B. There are not enough ______________________ for all living things
1. _____________________
3. ______________________
2. _____________________
4. ______________________
C. Only living things that can obtain resources will _________________
III. Adaptations
A. Something that allows living things to obtain ___________________________
B. Something that allows living things to produce many _________________________
C. Something that allows living things to ______________________________________
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IV. Evolution
A. Living things evolve. Evolve is another word for ______________________
B. Living things evolve _________________________________________________
V. Natural Selection
A. Living things with ___________________________ that help them to live in their
______________________________ will survive better.
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Name _______________________________________________________ Date ___________
THE NATURAL SELECTION OF WOOLYBOOGERS
There is a very rare animal called a woolybooger. There are 5 different species of woolyboogers
and all 5 woolyboogers have different mouths shown below:
Type 1
Type 2
Type 3
Type 4
Type 5
In this lab, you will experiment with how effective each woolybooger is at obtaining food, as
well as how effective their prey are at avoiding capture.
PROCEDURE:
1. Class splits into 5 groups. Each group receives a different “mouth” which represents its set of
genes.
2. Class goes outside to grassy spot where 100 beans of each type (total of 400 beans) are
dispersed.
3. At signal, class will collect beans for 3 minutes, count them, and record data by groups.
4. Record data for ALL GROUPS on the data sheet. The groups with the least beans become
extinct.
5. For each color, the number of beans that remain in the grass will be doubled and added by
dispersal in the area.
Example: 50 green beans collected from 100. This leaves 50, therefore add another 100 making
the new total 150. Do the same with the other colors.
6. Repeat four more times (four more generations).
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DATA SHEET: NATURAL SELECTION OF BEAN HUNTERS
Record the number of beans COLLECTED, of each color, and by each group
1st
Generation
YELLOW
WHITE
BLACK
GREEN
TOTALS
2nd
Generation
YELLOW
WHITE
BLACK
GREEN
TOTALS
3rd
Generation
YELLOW
WHITE
BLACK
GREEN
TOTALS
4th
Generation
YELLOW
WHITE
BLACK
GREEN
TOTALS
5th
Generation
YELLOW
WHITE
BLACK
GREEN
TOTALS
Group1
Group2
Group3
Group4
Group5
Group1
Group2
Group3
Group4
Group5
Group1
Group2
Group3
Group4
Group5
Group1
Group2
Group3
Group4
Group5
Group1
Group2
Group3
Group4
Group5
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TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
QUESTIONS:
1. Which woolybooger became extinct first, and why?
2. Why did we double the number of beans that were left uncollected? (What was it simulating?)
3. Did any bean group become extinct? If so, which one(s)?
4. What is a good trait for a bean in this experience, and why?
5. What is the best suited trait (mouth) in this experience, and why?
6. How does this experiment relate to naturally occurring populations?
7. How might a group of organisms in nature avoid extinction due to competition?
8. Explain why evolution occurs at the POPULATION level and NOT SPECIES.
9. Develop a possible evolutionary advantage a bean group (or all) could have that would allow
them to better survive.
10. Develop a scenario in which the “fittest” bean would no longer have such an advantage.
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VI. Evidence of Evolution
How do we know these animals lived here?
A. Fossils: ____________________________________________________________________
How do we know organisms are related? (Page 384)
B. Homologous Structures:
_____________________________________________________________________________
_____________________________________________________________________________
Turtle
Alligator
Bird
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Mammal
C. Similar Development
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ICE AGE MOVIE QUESTIONS
(15 POINTS)
1. In the movie, what is happening to the Earth? ¿En la película, qué está pasando a la tierra?
____________________________________________________________________________
2. What are 2 animals in this movie that are extinct today? ¿Cuáles son 2 animales en esta
película que están extintos hoy?
____________________________________________________________________________
3. What animals are alive today that resemble them? ¿Qué animales son vivos hoy que se
asemejan a ellos?
______________________________________________________________________
4. Why is Diego travelling with Sid and Manny? ¿Por qué Diego está viajando con Sid y
Manny?_____________________________________________________________________
____________________________________________________________________________
5. What happened to Manny’s family? ¿Qué pasó a la familia de Manny?
_____________________________________________________________________________
_____________________________________________________________________________
6. Write 1 thing that changes about Manny and Diego throughout the movie. Escriba 1 cosa que
cambie sobre Manny y Diego a través de la película.
_____________________________________________________________________________
_____________________________________________________________________________
7. Describe how this movie is relevant to evolution. Describa cómo esta película es relevante a
la evolución.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
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The Evolution of Populations
I. What is a Population?
A. Definition: _____________________________________________________________
_________________________________________________________________________
B. Evolution happens in ___________________________. Evolution DOES NOT happen
in ____________________________.
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II. Why do Populations evolve?
A. Natural Selection _________________________________________________
______________________________________________________________________
______________________________________________________________________
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There are 3 models of Natural Selection, Pages 398-399 in Book. Draw each
model.
Directional Selection
Disruptive Selection
Stabilizing Selection
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Questions
1. In the Directional Selection graph, does beak size get smaller or larger?
________________________________________________________________
2. In the Disruptive Selection graph, what happens to the average?
__________________________________________________________________
3. In the Stabilizing Selection graph, does the number or DIFFERENT birth
masses increase or decrease?
__________________________________________________________________
B. Genetic Drift
1. Definition: _______________________________________________________
______________________________________________________________________
2. In this example:
__________________________________________________________________
__________________________________________________________________
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3. A second example of genetic drift is:
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
4. Comparing Natural Selection and Genetic Drift
a. ___________________________________________________________
__________________________________________________________________
__________________________________________________________________
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b. ___________________________________________________________
__________________________________________________________________
__________________________________________________________________
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C. Mutations
1. Definition: __________________________________________________
__________________________________________________________________
2. Draw an example of a mutation
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D. Migration
1. Definition: _______________________________________________________
__________________________________________________________________
Year
Location
Bird Color
2000
Cuba
Red
2000
Mexico
Yellow
Year
Location
Bird Color
2008
Cuba
Red, Yellow,
Orange
2008
Mexico
Yellow
1. What color birds migrated to Cuba? _________________________________
2. Did evolution happen? How do you know? _____________________________
__________________________________________________________________
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Questions:
1. Does evolution happen to one thing or a population of things?
__________________________________________________________________
2. What is 1 example of Natural Selection?
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
3. What are the 3 models of Natural Selection?
__________________________________________________________________
__________________________________________________________________
4. Which model of Natural Selection shows a population that becomes more like
each other? ________________________________________________________
5. A forest has 10 tall trees and 10 short trees. People come to the forest and cut
down 5 tall trees. Is this an example of Natural Selection or Genetic drift?
_________________________________________________________________
6. There are 100 green bugs in a population. One of the green bugs has a red baby
bug. What type of evolution is this an example of? _________________________
7. There are only green bugs in Mexico and only red bugs in Cuba. A bug from
Mexico flies to Cuba. The next year, there are red and green bugs in Cuba. What
type of evolution is this an example of? __________________________________
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III. How do we know Populations evolve?
A. The Hardy-Weinberg Principle
1. Definition: __________________________________________________
__________________________________________________________________
5 things are needed for a population to stay the same (NOT EVOLVE)
1. Random Mating:
__________________________________________________________________
__________________________________________________________________
2. Very Large Population: _____________________________________________
3. No migration:
__________________________________________________________________
__________________________________________________________________
4. No mutations: ____________________________________________________
5. No Natural Selection:
__________________________________________________________________
__________________________________________________________________
If a population is not in equilibrium, the population must be changing or evolving
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2. A math equation is used to define genetic equilibrium:
Equations: p2 + 2pq + q2 = 1
HD
He HR
(P x P = PP = P2)
p +
D%
R%
(q x q = qq = q2)
(P x q = pq)
Hom. Dominant
q =1
Heterzygous
Hom. Recessive
Example 1: Total population = 200 bugs
If 50 bugs are Hom. Recessive, how many bugs are Hom. Dominant &
heterozygous?
50/200 = .25 (25%) bugs are qq… The square root of .25 gives q… √.25 = .5
q = .5
p + .5 = 1
Solve for p
p = .5
Plug in .5 for the other equation
p2 + 2pq + q2 = 1
pp + 2pq + qq = 1
(.5 x .5) + 2 ( .5 x .5) + ( .5 x .5) = 1
.25 + .50
+ .25 = 1
50 bugs are HD 100 bugs are He
50 bugs are HR
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Example 2: Total population = 400 bugs
If 60 bugs are Hom. Recessive, how many bugs are Hom. Dominant &
heterozygous?
60/400 = .15 (15%) bugs are qq… The square root of (.15) gives q… √.15 = .387
q = .387
p + .387 = 1
Solve for p
p = .613
Plug in .613 for the other equation
p2 + 2pq + q2 = 1
pp + 2pq + qq = 1
(.613 x .613) + 2 ( .613 x .387) + ( .387 x .387) = 1
.38 + .47
38% of 400 = 152
152 are HD
+ .15 = 1
47% of 400 = 188
188 are He
50 bugs are HD 100 bugs are He
15% of 400 = 60
60 are HR
80 bugs are HR
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Practice Problems
Equations
______________________________________________________
1. There are 100 bugs in a population. If green is recessive to red and there are 20
green bugs…
a. How many bugs are Heterozygous? ____________
b. How many bugs are Homozugous Dominant? ____________
2. There are 200 trees in a population. If 15 trees are short, and short is recessive
to tall…
a. How many trees are homozygous dominant? ____________
b. How many trees are heterozygous? ____________
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Something Fishy Going On Here!
Introduction:
Understanding natural selection can be
confusing and difficult. People often
think that animals consciously adapt to
their environments & that the giraffe can permanently stretch its neck, the polar bear can turn itself white - all
so that they can better survive in their environments.
In this lab you will use fish crackers to help further your understanding of natural selection and the role of
genetics and gene frequencies in evolution.
Background: Facts about the 'Fish'
1. These little fish are the natural prey of the terrible fish-eating sharks - YOU!
2. Fish come with two phenotypes: gold and Red:
a. Gold: this is a recessive trait (r); these fish taste yummy and are easy to catch.
b. Red: this is a dominant trait (R); these fish taste salty, are sneaky and hard to catch.
3. You, the terrible fish-eating sharks, much prefer to eat the yummy gold fish; you eat ONLY gold fish unless
none are available in which case you resort to eating Red fish in order to stay alive.
4. New fish are born every 'year'; the birth rate equals the death rate. You simulate births by reaching into the
container of 'spare fish' and selecting randomly.
5. Since the gold trait is recessive, the gold fish are homozygous recessive (rr). Because the Red trait is
dominant, the Red fish are EITHER homozygous or heterozygous dominant (RR or Rr).
Hardy-Weinberg:
G. H. Hardy, an English mathematician, and W.R. Weinberg, a German physician, independently worked out
the effects of random mating in successive generations on the frequencies of alleles in a population. This is
important for biologists because it is the basis of hypothetical stability from which real change can be
measured.
For fish crackers, you assume that in the total population, you have the following genotypes, RR, Rr, and rr.
You also assume that mating is random so that rr could mate with rr, Rr, or RR; or Rr could mate with rr, Rr,
or RR, etc. In addition, you assume that for the gold and brown traits there are only two alleles in the
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population - R and r. If you counted all the alleles for these traits, the fraction of 'r' alleles plus the fraction of
'R' alleles would add up to 1.
The Hardy-Weinberg equation states that: p2 + 2pq + q2 = 1
This means that the fraction of pp (or RR) individuals plus the fraction of pq (or Rr) individuals plus the
fraction of qq (rr) individuals equals 1. The pq is multiplied by 2 because there are two ways to get that
combination. You can get R from the male and r from the female OR r from the male and R from female.
If you know that you have 16% recessive fish (rr), then your qq or q2 value is .16 and q = the square root of
.16 or .4; thus the frequency of your r allele is .4 and since the sum of the r and R alleles must be 1, the
frequency of your R allele must be .6. Using Hardy Weinberg, you can assume that in your population you
have .36 RR (.6 x .6) and .48 Rr (2 x .4 x .6) as well as the original .16 rr that you counted.
Procedure:
1. Get a random population of 10 fish from the 'ocean.'
2. Count gold and red fish and record in your chart; you can calculate frequencies later.
3. Eat 3 gold fish; if you do not have 3 gold fish, fill in the missing number by eating red fish.
4. Add 3 fish from the 'ocean.' (One fish for each one that died.) Be random. Do NOT use artificial selection.
5. Record the number of gold and red fish.
6. Again eat 3 fish, all gold if possible.
7. Add 3 randomly selected fish, one for each death.
8. Count and record.
9. Repeat steps 6, 7, and 8 NINE more times.
10. Fill in the 2 charts on the next page.
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DATA
Generation # Gold
# Red
p2
q2
p
q
2pq
1
2
3
4
5
6
7
8
9
10
Analysis:
1. Make a bar graph of your data. On the 'x' axis put the generations (1, 2, etc.) and on the
'y' axis put frequency (0-1). Plot both the q and p for your data. Use one color for
each allele. What generalizations would you make about your results?
2. Explain which phenotype is NOT favorable to the fish and why?
3. What process is occurring when there is a change in genotypic frequencies over a long
period of time?
4. What happens to the recessive genes over successive generations and why?
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