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Honors Biology Lab Manual

Unit 6: Mechanisms of Evolution

Name: _______________________________________________

Teacher: _________________________

Period: ________

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Unit 6: Mechanisms of Evolution Activities for Portfolio

**As you complete your portfolio, please highlight labs you are choosing for reflection/grading**

Learning Targets (p 5)

Claim, Evidence, Reasoning Artificial Selection of Dogs (p 6-8)

Artificial Selection Dog Breeding (p 9-11)

Evolution by Natural Selection(p 12-21)

Natural Selection of Butterflies (p 22-28)

Natural Selection of Peppered Moths (p 29-31)

Natural Selection pHet simulation (p 32-33)

Data Analysis: Effects of Natural Selection on Finch Beak Size (p 34-38)

Antibiotic Resistance in Bacteria (p 39-49)

Population Genetics: Fishy Frequencies (p 50-53)

Salamander Speciation (p 54-59)

Pollenpeeper Speciation (p 60-67)

Utopian Islands Speciation (p 67-70)

Unit Reflection (p 71-75)

Article (p 76-77)

Personal Choice (p 78-79)

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Unit 6 Portfolio: Grading Rubric (100 points)

Category 4 3 2 1 0 Score Weight Total Points

Lab 1*

All data, calculations, and pre/post lab questions are complete and accurate.

1-2 data, calculations, or

pre/post lab questions are incomplete or

incorrect.



incorrect.

5 data, calculations, or


incorrect.

> 5 data, calculations, or


incorrect.

3.75 /15

Lab 2*




incorrect.



incorrect.



incorrect.



incorrect.

3.75 /15

Lab 3*




incorrect.



incorrect.



incorrect.



incorrect.

3.75 /15

Reflection A

Labs are thoroughly

connected back to specific, restated learning targets

Labs are connected back

to specific, restated learning

targets

Labs are listed or stated with little

to no explanation of connections

Not included

1.0 /3

Reflection B

Learning from labs is thoroughly

explained with specific content

included

Learning from labs is explained

with some general content

included

Learning from labs is stated

with little to no content included

Not included

1.0 /3

Reflection C

Labs are thoroughly

compared and contrasted using a graphic organizer (Venn, T-Chart…)

Labs are compared and

contrasted using a graphic

organizer (Venn, T-Chart…)

Labs are compared and

contrasted

Not included

1.0 /3

Reflection D

Specific example of issues with any

labs or content thoroughly

explained and how issues were

corrected/learned from

Specific example of issues with any

labs or content stated and how

issues were corrected/learne

d from

Specific example of issues with

any labs or content stated,

but doesn’t include what was

learned

Not included

1.0 /3

Reflection E

Any labs or whole unit are

thoroughly connected to the real world with

specific examples.


connected to the real world with

specific examples.


stated to the real world with some

examples.

Not included

1.0 /3

3

Article ^

Article chosen relates to the

unit, is summarized, a

copy is included in the portfolio, and

3 or more strong

connections to the unit are

made.


unit, is summarized, a copy is included

in the portfolio, 2 strong

connections to the unit are made


unit, is summarized, a copy is included

in the portfolio, 1 strong

connection to the unit is made


unit, is summarized, and

a copy is included in the

portfolio. No connection or

very weak connections to

the unit are made

No article is included,

summarized, and connected

back to unit.

3.75 /15

Personal Choice

Item is original and complete

with a rationale that connects 3 or

more concepts to the unit. A thorough and

accurate explanation of the concepts is

included.


with a rationale that connects 2 concepts to the

unit. An accurate explanation of the

concepts is included.


with a rationale that connects 1

concept. An accurate

explanation of the concept is

included.

Item is original and sloppy or

incomplete. No rationale of the

concepts is included or

item/explanation of concepts is

inaccurate.

No personal choice included or item is not

original (copied from Google,

labs, handouts, etc).

3.75 /15

Lab Completion (not ** labs)

All labs from the unit are complete.

1 lab from the unit is

incomplete.

2 labs from the unit are

incomplete.

3 labs from the unit are

incomplete.

More than 4 labs from the

unit are incomplete.

1.5 /6

Grammar & Spelling

1 or fewer errors in

complete sentences, spelling,

grammar, & punctuation.

2 errors in complete sentences, spelling,


3 errors in complete sentences, spelling,


4 errors in complete

sentences, spelling,


5 or more errors in complete

sentences, spelling,


1.0 /4

Total Score /100

* If you do not mark (*) the 3 labs you wish to be graded and/or highlight them in your table of contents, the first 3

labs in your binder will be graded!*

^If you do not include a copy of your article, your score will be dropped by 1 point in the rubric (ex: you meet the

criteria for a “3” but have no copy of the article so you will earn a “2”)^

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Unit 6 Learning Targets: Mechanisms of Evolution

I can:

1. Construct an explanation based on evidence that the process of evolution by natural selection primarily

results from four factors:

i. The potential for a species to increase in number,

ii. The heritable genetic variation of individuals in species due to mutation and sexual reproduction,

iii. Competition for limited resources, and

iv. The proliferation of those organisms that are better able to survive and reproduce in the

environment.

2. Apply concepts of statistics and probability to support explanations based on evidence that organisms with an

advantageous heritable trait tend to increase in proportion to organisms lacking this trait.

3. Construct an explanation based on evidence for how natural selection leads to adaptation of populations.

4. Evaluate the evidence supporting claims that changes in environmental conditions may result in:

a. Increases in the number of individuals of the same species,

b. The emergence of new species over time, and

c. The extinction of other species.

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Claim, Evidence, Reasoning: Artificial Selection of Dogs

Assignment: You are a dog breeder. You have been contacted by a scientist who wants dogs that could be used to see

and retrieve waterfowl (ducks and geese) from lakes in the area so the birds can be tagged and re-released. The birds

are very skittish (scare easily) and must be retrieved unharmed and with a minimum amount of stress.

Part I:

Claim: Desired features of the new breed

1. For each feature below, circle the desired form you ideally want your dogs to have.

2. For features that you do not think will affect your breed’s ability to perform the given task, circle “any.”

Physical Features Desired Form

Smell above average average below average any

Sight above average average below average any

Hearing above average average below average any

Speed above average average below average any

Endurance above average average below average any

Strength above average average below average any

Coat color black brown white any

Hair length long medium short any

Behavioral Features Desired Form

Trainability high average low any

Disposition vicious compatible meek any

Bark very loud average very quiet any

3. Which two traits do you think are most important for your new breed to inherit? Why?

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Part II:

Evidence: Selecting & mating your breeds

4. Obtain a Dog Breeds handout from your teacher. Analyze the traits of the species available to you for breeding

your dogs. Select two dog breeds with the features most likely to produce a breed with the features you need. You

will have to prioritize the features since no two breeds will likely have the exact combination of traits you desire.

5. Dog breeds chosen to mate: ______________ X ___________________

6. Choose which dog breed will be the mother and which dog breed will be the father. This breeding pair will

produce 3 puppies; puppies may inherit traits from the mother or from the father.

7. For this exercise, we will determine traits inherited by a flip of a coin: Heads = the female's (mother's) feature,

tails = the male's (father's) feature.

8. Since there are three offspring, you will flip a coin three times for each trait to be inherited.

9. Keep track of the results of your coin flips in the table below.

Puppy Traits

Puppy #1 Puppy #2 Puppy #3

Physical Features

Smell

Sight

Hearing

Speed

Endurance

Strength

Coat color

Hair length

Behavioral Features

Trainability

Disposition

Bark

10. On a blank piece of paper, choose one of your puppies to draw (the one that closest matches your claim). Below

the drawing, indicate which features were inherited from each adult. Also, label the significant (desired) features

inherited.

11. After you have completed your drawing, compare your puppy’s picture with the others from your class who

selected the same set of parents.

12. Take notice of the variation of the dogs portrayed and remember that traits are randomly inherited.

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Part III:

Reasoning: does your evidence support your claim?

1. Which of the resulting dogs do you think will best serve the assigned task? Explain.

2. Is there a single individual that is perfect for the task? If you were to conduct the dog breeding for another

generation, which pups would you select to be the parents for the next generation?

3. In your own words, describe the process of artificial selection in 5-6 sentences.

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Artificial Selection: Dog Breeding

1. Go to: http://pbskids.org/dragonflytv/games/game_dogbreeding.html

2. Fill in the chart as you work.

Level

Desired Trait

Number of Attempts Observations/Explanation

1

Black

2

Long Hair

3

Medium

Floppy Ears

4

Brown

Long Hair

5

Black

Long Hair

Straight Ears

6

Brown

Long Hair

Floppy Ears

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http://pbskids.org/dragonflytv/games/game_dogbreeding.html

http://pbskids.org/dragonflytv/games/game_dogbreeding.html

3. Read the following article and answer the questions that follow.

● Article One: http://www.livescience.com/8420-incredible-explosion-dog-breeds.html

a. What claim is made about how we got so many different kinds of dogs?

b. What evidence is provided in each article to support their claim?

4. Read the following article and answer the questions that follow.

● Article Two http://sciencenordic.com/dna-reveals-new-picture-dog-origins

a. What claim is made about how we got so many different kinds of dogs?

b. What evidence is provided in each article to support their claim?

5. Did the articles you read in questions 3 & 4 above have the same claim and evidence? What can you do to

determine if either claim and evidence is reliable?

6. People are breeding dogs based on looks and behavior… go to: http://www.akc.org/dog-breeds/

Choose any 3 breeds, click “history” and tell what characteristics they were breed for and why.

Name of Dog Original Breeding Basis

(Desired behavior/appearance)

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http://sciencenordic.com/dna-reveals-new-picture-dog-origins

http://www.livescience.com/8420-incredible-explosion-dog-breeds.html



http://www.akc.org/dog-breeds/

http://www.akc.org/dog-breeds/

7. Google image “tea cup pups.” Why do you think that most people are now buying “tea cup dogs”? Give 3 different

reasons.

8. Google search to find out some of the problems with tea cup pups. List at least 3 different problems people have

noticed.

9. Sum It Up: These tea cup dogs were not around 20 years ago. Think about the breeding game you played and

what you have read. Give a thorough explanation of how artificial selection gave rise to these dogs.

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Evolution by Natural Selection

Part I. Mice Living in a Desert

These drawings show how a population of mice on a beach changed over time.

1. Describe how the population of mice is different in figure 3 compared to figure 1. Explain what happened to cause

this difference.

An adaptation is any characteristic that increases fitness, which is defined as the ability to survive and reproduce.

2. For the mice in the figure, what characteristic was an adaptation that increased fitness?

3. The term fitness can have two different meanings, depending on what subject you are discussing. Answer the

following questions to show the two different meanings of fitness.

What does the term fitness mean when biologists are discussing evolution?

What does the term physical fitness mean?

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Suppose a population had three female mice with the following characteristics.

Color of Fur White Gray Black

Running speed 5 cm/sec. 6 cm/sec. 8 cm/sec.

# offspring produced by each female 5 15 8

Age at death 3 months 6 months 3 months

4. From an evolutionary point of view, which mouse would be the fittest? How do you know that this mouse would be

the fittest?

A characteristic which is influenced by genes and passed from parents to offspring is called a heritable trait. For

example, fur color is a heritable trait for mice.

A heritable trait that increases fitness is called an adaptive heritable trait. Individuals with an adaptive heritable

trait generally produce more offspring than individuals that do not have this trait. For example, on gray sand, gray

fur color is an adaptive heritable trait which allows mice to survive longer and have more litters of baby mice.

This figure shows what would happen if a population of mice in an area of gray sand began with a pair of white mice,

a pair of gray mice, and a pair of black mice in generation 1. Because the gray mice survive longer and have more

babies, the percent of mice with gray fur increases from 33% of the generation 1 adults to 54% of the generation 2

babies.

5a. Which type of baby mouse would be most likely to survive to become an adult who reproduces?

___ white ___ gray ____ black

5b. For generation 2 adults, would you expect the percent gray to be

___ <54% ____ 54% ___ >54%?

5c. Explain why the percent of adult mice with gray fur would increase from generation 1 to generation 2. Include

differences in survival and reproduction in your explanation. Also, include the terms fitness and adaptive heritable

trait in your answer.

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6a. A population of mostly gray mice living on a patch of gray sand are asleep in their burrows. While the mice are

sleeping, the gray sand is replaced by white sand. (Perhaps the owner of the desert has a plan to attract more

tourists.) Think about what would happen to the population of mice on the white sand. After several generations,

most of the mice would have _____________ fur.

(white/gray/black)

6b. Explain how the change in the color of the sand could result in a change in the most common fur color in this

population of mice.

7. When mice live on gray sand, which color fur is an adaptive heritable trait? Justify your response.

When mice live on white sand, which color fur is an adaptive heritable trait? Justify your response.

Is the same trait adaptive in both environments? Justify your response.

These examples illustrate how, over time, an adaptive heritable trait tends to become more common in a

population . Because the trait is adaptive, individuals with this trait generally produce more offspring. Because the

trait is heritable, offspring generally have the same trait as their parents. Therefore, over time, the adaptive

heritable trait tends to become more common in the population. This process is called natural selection.

8. Explain how these drawings illustrate an example of natural selection. Include the term "adaptive heritable trait" in

your answer.

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Part II. Simulation of Natural Selection

Next, you will play a simulation game to demonstrate how natural selection works. A simulation is a good way to

mimic and simplify the process so we can understand how evolution by natural selection works in real populations.

This simulation involves two populations of pom-poms. One population lives in a Black Forest habitat and the other

population lives in a Red Grassland habitat. The only threat to the pom-pom creatures is the presence of ravenous

hunters (that’s you!).

Each pom-pom is either red or black, and each hunter will have either a fork or spoon as his or her feeding structure.

The differences in pom-pom color and hunter feeding structures are heritable. The offspring of a pom-pom that

survives to reproduce has the same color as its parent. Similarly, the offspring of a hunter that survives to reproduce

has the same feeding structure as his or her parent.

9. Your teacher will scatter an equal number of black and red pom-poms on the Black Forest and on the Red

Grassland. Which color pom-pom do you think will be more likely to be captured and eaten in each habitat?

Black Forest __________ Red Grassland __________

Explain the reasons for your predictions.

10. You will be given a feeding structure (a fork or spoon) and a cup which will serve as your “stomach”. To capture a

pom-pom, you must use only your fork or spoon to lift the pom-pom from the habitat and put it into your cup. Which

feeding structure do you think will allow a hunter to capture more pom-poms in each habitat?

Black Forest (represented by a rough black material such as faux fur) _____________

Red Grassland (represented by a red fleece material) ______________

Explain the reasons for your predictions.

Simulation Procedure

1. Go to your assigned habitat: Black Forest or Red Grassland.

2. Rules for Feeding:

a. Start and stop when your teacher says to.

b. You must pick up each pom-pom with your feeding implement and drop it into your cup. You may not

tilt your cup and scoop pom-poms into your cup.

c. Once a pom-pom is on a classmate's fork or spoon it is off limits.

3. After feeding, count how many pom-poms you have eaten and line up with your classmates who were

feeding on the same habitat, from fewest pom-poms eaten to most pom-poms eaten. Then, follow the

instructions of the Student Helper for your group.

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4. While your teacher is busy helping the surviving pom-poms to reproduce on each habitat, discuss the

following questions with your group:

a. Which feeding structure contributed to greater fitness in your habitat?

b. What characteristics of forks and spoons increased or decreased fitness in your habitat?

5. Next, you will run through the simulation one more time.

11. For each habitat, evaluate the data on the board that shows number of hunters with spoon vs. fork feeding

structures. Were there any changes from generation 1 (the beginning of the simulation) to generation 3 (the end of

the second cycle)? If yes, describe the change or changes and propose possible explanations.

12. Copy the pom-pom data from the table displayed by your teacher into the table below. Then, for each generation

of pom-poms in each habitat, calculate the percent of each color.

Pom-poms in the Black Forest Pom-poms in the Red Grassland

Black Red Total Black Red Total

Generation 1

Number

Percent

100%

100%

Generation 2

Number

Percent

100%

100%

Generation 3

Number

Percent

100%

100%

13. Use the data to complete the following graphs. This will help you to see the trends in the percent of pom-poms of

each color over the three generations in each habitat.

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14a. For each habitat, describe whether one color pom-pom became more common while the other color pom-pom

became less common.

Black Forest:

Red Grassland:

14b. At the beginning of the simulation, the pom-pom populations were half red and half black in both the Black

Forest and the Red Grassland. Explain why the trends in pom-pom colors differed in these two different habitats.

15. Did any individual pom-poms change color or adapt? If not, then why did the colors of the pom-poms in the final

populations differ from the colors of the pom-poms in the original populations?

Notice that natural selection does not refer to individuals changing. Rather, the frequency of adaptive heritable

traits in a population changes as a result of natural selection.

16a. What do you think would happen to the pom-pom population if the black forest experienced a prolonged

drought so all the trees died and the habitat became red grassland? First, make your prediction of what would

happen if the population of pom-poms in the black forest at the beginning of the drought included both red and black

pom-poms.

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16b. Next, think about an alternative scenario. Suppose that natural selection over many generations had eliminated

all the red pom-poms in the black forest habitat so only black pom-poms survived. After that, a prolonged drought

resulted in this habitat turning into a red grassland. Would natural selection for pom-pom color occur? Why or why

not?

16c. Based on this example, explain why evolution by natural selection can only occur if there is variation in a trait.

17a. Suppose that your class repeated the simulation, but this time all the hunters were blindfolded so they could

only find pom-poms by touch. For each habitat, predict the proportion of red and black pom-poms in the population

at the end of the simulation. (Remember that at the beginning of the simulation half the pom-poms were red and half

were black.)

Black Forest:

Red Grassland:

17b. Explain your reasoning.

17c. Based on this example, explain why evolution by natural selection can only occur if the variation in a trait results

in differences in fitness.

18. Next, think about what would happen if your class repeated the simulation with hunters that could see, but

pom-pom color was not heritable. In other words, the color of pom-pom offspring would not be related to the color

of their parents. No matter how many pom-pom parents were red or black, half of the offspring would be red and half

would be black. Based on this example, explain why evolution by natural selection can only occur if the variation in a

trait is heritable.

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This simulation provides a useful basis for understanding many aspects of natural selection. However, it is important

to note that, because a simulation necessarily simplifies the process that it mimics, there will be important differences

between the simulation and the actual biological process. For example:

● In our simulation visual predation was the only factor that influenced mortality and reproduction of the

pom-poms. In contrast, for real biological organisms, mortality is influenced by additional factors (e.g.

infection) and reproductive success is influenced by other factors in addition to survival.

● Also, in our simulation, each offspring had the exact same phenotype as its only parent, but, for most

biological organisms, some of the offspring will have different characteristics than their parents.

Because of these differences between our simulation and reality, natural selection would be slower in real biological

populations. You will see an example of this in the next section.

Part III. Natural Selection in Action – The Peppered Moth

Peppered moths are active at night. During the day peppered moths rest on tree trunks and branches. Some of these

resting moths are eaten by birds.

19a. Researchers have found differences in mortality for the speckled and black forms of the peppered moth in

different types of environment.

Which form of the peppered moth do you think had higher mortality in forests in unpolluted areas where tree trunks

and branches are lighter? ___black ___ speckled

Which form of the peppered moth do you think had higher mortality in forests in areas where air pollution had

resulted in dark tree trunks and branches? ___ black ___ speckled

19b. Explain your reasoning.

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20. An individual peppered moth cannot change from black to speckled or vice versa. The difference between the

black and speckled forms of the peppered moth is a heritable trait; specifically, this difference results from different

alleles of a single gene. The allele for the black form (B) is dominant over the allele for the speckled form (b).

In these Punnett squares, circle the genotypes of all parents and offspring that would have the black phenotype.

Based on these Punnett squares, explain why peppered moths generally have offspring that look like their parents.

21. In the first column of this table, state three necessary conditions for evolution by natural selection to occur. (Hint:

See questions 16c, 17c and 18.) In the second column, explain the evidence that each of these necessary conditions is

satisfied by the black vs. speckled forms of the peppered moth.

Natural selection can only occur if: What is the evidence that the peppered moth example

meets this necessary condition?

Natural selection has occurred in peppered moth populations. The black form of the peppered moth was very rare in

England before 1850. After that date, industrialization resulted in air pollution which darkened tree trunks and

branches. In industrialized areas with dark tree trunks and branches, the frequency of black peppered moths

increased and speckled peppered moths became rare. The trend in southeastern Michigan was similar, although

industrialization began later; no black peppered moths were observed before 1929; by the 1950s more than 90% of

peppered moths were black.

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Beginning in the late 1950s, government

regulation resulted in decreased air pollution.

Consequently, tree trunks and branches became

lighter.

As would be expected, there was a decrease in

the percent of peppered moths that were black.

This decrease is shown for one area in England

(black dots) and one area in Michigan (black

diamonds for 1959-1962 and 1994-1995).

The open circles in the graph represent the

trend predicted by a model of natural selection

which incorporated experimental estimates of

higher mortality rates for black peppered moths

in unpolluted environments.

22. Which trait was an adaptive heritable trait for peppered moths in industrialized areas with dark tree trunks and

branches? ___ black form ___ speckled form

Which trait is an adaptive heritable trait for peppered moths in unpolluted areas with lighter tree trunks and

branches? ___ black form ___ speckled form

23. A student wrote the following explanation of what caused the increase in the black form of the peppered moth

after 1850 and then the decrease in the black form after 1950.

When air pollution resulted in dark tree trunks and branches, the peppered moth needed to be dark

so it would not be seen and eaten by birds. When air pollution was reduced so tree trunks and

branches were lighter, the peppered moth needed to be lighter so it would not be eaten by birds.

Write a scientifically more accurate explanation of what happened to cause the trends in the proportion of black

peppered moths.

24a. Many people think of the process of evolution as "survival of the fittest". How do you think most people

interpret "survival of the fittest"?

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24b. Compare and contrast the common conception of survival of the fittest with the scientific definition of which

organisms are the fittest in terms of natural selection.

25. Use the peppered moth example to illustrate the following generalization: Natural selection acts on individuals,

but only populations evolve.

Natural Selection of Butterflies Lab

Purpose:

This simulation was invented by G. Ledyard Stebbins, a pioneer in the evolution of plants. The purpose of the

simulation is to illustrate the basic principles and some of the general effects of evolution by natural selection.

Introduction:

Natural selection acts at the level of individuals. It is the individual organism that lives or dies, reproduces or fails to

reproduce because of its characteristics. When more individuals with a particular trait survive then the overall

population will change over time — it will be made up of more and more individuals with that successful

characteristic. This change over time in the population is evolution.

For example, let’s imagine that it is a dry year and food is scarce. There is a flock of birds. The birds in the flock that

have the larger, sturdy beaks are the only ones that can eat what are usually hard-to-crack seeds. So those large-beak

birds get more food than the smaller beak birds and they therefore survive more. Since they survive more they also

get to reproduce more — lay more eggs and have more babies. Now more of the birds in the next generation will

inherit the large beak from their parents. So the next generation flock will be made up of more large-beak birds. If this

drought stayed for many years then over time this bird species may end up being made of mostly large-beak birds and

very few small beak birds. We would therefore say that this flock of birds had evolved over time.

Evolution by natural selection, as first proposed by Charles Darwin, includes four conditions:

1. Variation: Variation means that there are differences between the individuals in a population. In this lab, variation

is simulated by different colored paper dots. For the purposes of this lab, these dots are assumed to be different

colored butterflies of the same species — a species that has a range of colors in one population living in an area

together.

2. Inheritance: The variations that exist within the population must be inheritable from parents to offspring. The

characteristics can be passed on in genes. Darwin clearly recognized that this was the case, although he did not know

about genes or DNA. In this lab, inheritance is "true breeding" — that is, offspring inherit the exact color of their

parents, for instance red butterflies only reproduce red butterflies.

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3. Overproduction: As a result of reading a famous essay of his time — Essay on the Principle of Population by

Malthus — Darwin realized that in natural populations more offspring are born than can possibly live to reproduce. In

this simulation, overpopulation is modeled by having only part of each generation's offspring survive to be able to

reproduce. The rest of the individuals are eaten by a predator.

4. Differential Survival and Reproduction: Given the three conditions described above, certain individuals will survive

and reproduce more often than others, and these individuals and their offspring (the ones with the successful traits)

will therefore become more common over time. This, in a nutshell, is evolution by natural selection.

In natural environments, one of the most noticeable forms of natural selection is predation. Predators eat other

organisms, while prey is eaten by them. In our natural selection “game” (actually a simulation), we will study a closely

related phenomenon — the evolution of protective coloration. Many animals, especially insects, are very well

camouflaged against being seen or found by their predators, especially birds. In some cases, the insects mimic some

part of their habitat, such as a leaf. The question under investigation in this game is, how do mimicry and protective

coloration evolve?

Procedure:

In this simulation, beads of different colors represent butterflies. The different colors represent different color

variations within one species of butterfly . We will begin with equal numbers of each color butterfly (each color bead)

at the start of the game. It is assumed that the different colors are inherited genetically.

Step 1: Divide into two-person teams. Each team will begin with a different, colored cloth "environment" (~16” x 16”

square). One person should be designated as the first “Butterfly Predator”. The Butterfly Predator should not be

allowed to see what goes on in Step 2, in order that her/his "predation" remains unbiased. The other team member

sets up the environment of butterflies.

Step 2: The other team member should count out four butterflies (beads) of each color — this is the starting

population for your environment — Generation #1. Record that in the data table. This same person should then

randomly scatter these butterflies on the cloth environment. Since there are five colors, there will be a total of

twenty butterflies in the environment to start with. This is the maximum population of butterflies your environment

can support — it’s the carrying capacity of your environment.

Step 3: The Butterfly Predator should now capture ten butterflies by picking up 10 beads as quickly as possible, one

bead at a time. Also, it is important that the Butterfly Predator break eye contact with the ground after each pick

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(look away from the cloth and then down again before each hunt). Be sure to pick the very first butterfly that you

see!

After all, time is energy (you're hunting, remember!), and so you can't afford to waste either time or energy by being

too picky. Put your "eaten" butterflies (beads) away; they have been removed from the population and do not get to

reproduce.

Step 4: Now collect your surviving butterflies (beads) from the cloth. Be sure to get all of them. There must be 10

surviving butterflies.

Step 5: Each surviving butterfly (bead) now reproduces. For each surviving butterfly, add one bead of the same color

from your reserve — your butterflies have now reproduced! So now you will have 20 butterflies again. This is

Generation #2. Count your butterflies and record the number of each color variant for Generation #2 only in the

Butterfly Predator’s data table.

Notice that there may not necessarily be the same number of each color any more — natural selection has been at

work in your population of individuals!

Step 6: Record your group’s data on the board so that class data for each environment can be collected.

24

Graph:

Graph the calculated percentages for the group or class data. This may be a line, bar or stacked bar graph.

Title: ________________________________________________________________________________________

KEY: ⬜ ⬜ ⬜ ⬜ ⬜

26

Analysis Questions: USE COMPLETE SENTENCES AND FOLLOW OEHS NON-NEGOTIABLES FOR WRITING!!!!

1. Describe the “environment” that you used in this simulation.

2. How many butterflies of each color did you start with in Generation #1? _________________

What was the frequency (percent) of each color at the start of Generation #1? ___________________

3. Did the number of each color stay the same from generation to generation? Explain.

4. Which color was the most fit in this environment? ________________________

a. How did you determine that color to be most fit?

b. How many of this color did you start with in Generation #1? ________________________

c. What was the frequency (percent) of this color at the start of Generation #1? __________________

d. How many of this color did you end up with in Generation #6? __________________

e. What was the frequency (percent) of this color at the start of Generation #6? __________________

f. Suggest a possible explanation of why this color was more fit in this environment.

5. Which color was the least fit in this environment? ________________________________

a. How did you determine that color to be least fit?

b. How many of this color did you start with in Generation #1? ________________________

c. What was the frequency of this color at the start of Generation #1? __________________

d. How many of this color did you end up with in Generation #6? ______________________

e. What was the frequency of this color at the start of Generation #6? __________________

f. Suggest a possible explanation of why this color was less fit in this environment.

27

Conclusion Questions: USE COMPLETE SENTENCES AND FOLLOW OEHS NON-NEGOTIABLES FOR WRITING!!!!

Separate from your specific environment used in this lab, consider the following "thought experiments" in natural

selection— what outcome might you expect under the following conditions described below.

6. If the environment was yellow and if the color differences were less distinct in a given environment (ex. all

butterflies were only shades of reds, oranges, and yellows), would you expect similar results? Explain what you would

expect and why.

7. What if you had a population with all 5 colors again, but the red butterflies made the predator very ill. Would you

expect similar results? Explain what you would expect and why.

8. What assumptions must you make about the predator’s abilities for your prediction to come about in the

question above (question 7)?

9. What if the red butterflies made the predator very ill and it learned to stay away from them, and there also was a

new group of butterflies very similar in color (a close red-orange color). What would happen to the red-orange

butterflies? Explain your answer.

28

10. Over the long term, what trait (ability) could be strongly selected for in the predator population in the situation of

similar color variants proposed above (question 9)?

11. In question 10 you identified a trait (ability) that would strongly benefit the predator population. Does that mean

the population will evolve that trait, since it is a “need” they have?

12. Consider the results in this lab. Did any of the butterflies survive because they chose to be the more fit color?

What did you learn about how natural selection works from this lab (review the 4 factors of evolution in learning

target #1)? (5-6 sentences)

29

Natural Selection Simulation: Peppered Moths

Go to the following website and go through the tutorial to answer the following questions.

http://peppermoths.weebly.com/

Life Cycle of Peppered Moths

1. Why are these moths called “peppered moths”?

2. List 2 predators of the peppered moth.

3. How are peppered moths able to hide themselves from predators?

4. How do the larvae adapt to the branches?

5. How long do peppered moths live?

Impact of Pollution

1. When was the first dark peppered moth found?

2. By the 1900’s were there more dark or light peppered moths?

3. What caused this change in the 1900’s?

4. What was one hypothesis as to why the moths were turning dark?

5. What actually caused the dark peppered moths?

6. Who proposed the idea of natural selection?

7. True or false, natural selection is still at work in the peppered moth?

Kettlewell’s Tests

1. When did Kettlewell conduct his study on the dark peppered moth?

2. Scientists test _________________ by making ________________ based on the theory.

30

http://peppermoths.weebly.com/

3. How many truths did Kettlewell develop if natural selection was at work in the peppered moth?

4. True or false, dark moths were absent before the industrial revolution.

5. How did Kettlewell directly study the moths?

6. What did he find?

Bird’s Eye View

Perform the 2 simulations, one for the dark forest and one for the light forest. Use your mouse to move the bird so

you can catch as many moths as possible.

Peppered Moth Analysis

1. Data table – Record % at the end of the 1 minute.

Percent Dark Moths Percent Light Moths

Lichen (light) Forest

Sooty (dark) Forest

2. Explain how the color of moths increases or decreases their chances of survival depending on the environment.

3. 500 light colored moths and 500 dark colored moths are released into a polluted forest. After 2 days the moths are

recaptured. Make a prediction about the number of each type that would be captured.

4. Explain what happened to the moths, using what you know about fitness and natural selection. (5-6 sentences)

31

5. Examine the table and construct a graph. Plot the years of the study on the X-axis, and the number of moths

captured on the Y axis. You should have 2 lines on your graph - one for light moths, and one for dark moths.

Collection Year # of Light Moths Captured # of Dark Moths Captured

1 537 112

2 484 198

3 392 210

4 246 281

5 225 337

6 193 412

7 147 503

8 84 550

9 78 567

10 66 592

Title: ___________________________________________________________________________________________

KEY: ⬜ ⬜

6. Explain in your own words what the graph shows regarding natural selection.

32

Natural Selection Computer Simulation

http://phet.colorado.edu/simulations/sims.php?sim=Natural_Selection

1. What are some interesting things that you have control over in the simulation?

2. What happens to the bunny population if a friend is never added? Why is this?

3. What happens when you add a friend?

4. What happens to the population if the food is super abundant and there are no predators?

Challenge 1: Find a way to make the bunnies take over with brown fur – you must have an environment and selection

factor (you can’t select “none”)! Fill in the table with your selections.

Mutation Environment Selection Factor Observations

Challenge 2: Find a way to make 200 bunnies when food is a selection factor – you must have a mutation and

environment (you can’t select “none”)! Fill in the table with your selections.


33



Challenge 3: Find a way for the bunnies to take over when the environment is the arctic – you must have a mutation

and selection factor (cannot select “none”)! Fill in the table with your selections.


1. On your own: Simulations are useful for understanding how natural processes work but are not always

representative of the real world. How does this simulation differ from what might happen in a true

ecosystem?

2. On your own: What changes would you make the simulation to make it a better representation of a true

ecosystem?

3. Complete the table below.

Word Definition Examples from simulation

Trait

Adaptation

Mutation

Limiting Factor

Biotic

Abiotic

Natural Selection

4. Explain what happened to the bunnies in the simulation, using what you know about fitness and natural

selection (consider the four factors of natural selection, learning target #1). (5-6 sentences)

34

Data Analysis: Effects of Natural Selection on Finch Beak Size BACKGROUND INFORMATION

Darwin thought that evolution took place over hundreds or thousands of years and was impossible to witness in a

human lifetime. Peter and Rosemary Grant have seen evolution happen over the course of just two years.

The Grants study the evolution of Darwin's finches on the Galapagos Islands. The birds have been named for Darwin,

in part, because he later theorized that the 13 distinct species were all descendants of a common ancestor. Each

species eats a different type of food and has unique characteristics developed through evolution. For example, the

cactus finch has a long beak that reaches into blossoms, the ground finch has a short beak adapted for eating seeds

buried under the soil, and the tree finch has a parrot-shaped beak suited for stripping bark to find insects. See the

diagram below for a comparison of finch beaks and diet.

35

The Grants have focused their research on the medium ground finch, Geospiza fortis,

on the small island of Daphne Major. Daphne Major serves as an ideal site for research

because the finches have few predators or competitors. (The only other finch on the

island is the cactus finch.) The major factor influencing survival of the medium ground

finch is the weather, and thus the availability of food. The medium ground finch has a

stubby beak and eats mostly seeds (see figure to the right) . Medium ground finches

are variable in size and shape, which makes them a good subject for a study of

evolution.

The first event that the Grants saw affect the food supply was a drought that occurred in 1977. For 551 days the

islands received no rain. Plants withered and finches grew hungry. The tiny seeds the medium ground finches were

accustomed to eating grew scarce. Medium ground finches with larger beaks could take advantage of alternate food

sources because they could crack open larger seeds. The smaller-beaked birds couldn't do this, so they died of

starvation.

In 1978 the Grants returned to Daphne Major to document the effect of the drought on the next generation of

medium ground finches. They measured the offspring and compared their beak size to that of the previous

(pre-drought) generations. They found the offsprings' beaks to be 3 to 4% larger than their grandparents'. The Grants

had documented natural selection in action.

While beak size is clearly related to feeding strategies, it is also related to reproduction. Female finches tend to mate

with males that have the same size beaks. These factors together can add to the development of new species.

The Grants return each year to Daphne Major to observe and measure finches. They have been collecting data on the

finches for over 25 years and have witnessed natural selection operating in different ways under different

circumstances.

To learn more about the Grants studies, watch the following video:

http://www.hhmi.org/biointeractive/origin-species-beak-finch

The graph on the next page shows the distribution of beak depths of the finch population before the drought (white

bars) and after the drought (black bars).

36

http://www.hhmi.org/biointeractive/origin-species-beak-finch

Distribution of beak depths in the breeding population of medium ground finches (Geospiza fortis) on

the island of Daphne Major in 1976 (white bars) and of the survivors of the 1977 drought (black bars).

The means of the two populations are indicated by the carets (^).

INTERPRETING THE GRAPH

The white bars represent the number of finches with a particular beak depth in 1976. The black bars indicate the

number of finches with a particular beak depth that survived the drought. The carets below the x-axis indicate the

mean beak depth of the 1976 population, before the drought (left caret), and the mean beak depth of the drought

survivors (right caret). The graph shows that there were fewer drought survivors than the original population and

that, on average, the drought survivors had a greater beak depth (i.e., larger beaks) than the original population.

DISCUSSION QUESTIONS

1. Analyzing the graph:

a. What is shown on the x-axis? Be specific by including units.

b. What is shown on the y-axis?

c. What is the distribution of data for the initial population (white bars)? Include the range of beak

depths and the mean.

d. What is the distribution of data for the drought survivors (black bars)? Include the range of beak

depths and the mean.

37

2. Make observations about the original population and survivors:

a. How does the size of the population differ (number of finches)?

b. How do the beak depth distributions differ?

c. How do the means differ?

3. How has the medium ground finch population changed after the drought?

4. Why do you think the Grants wanted to look at beak depth before and after the drought?

5. Why do you think the mean depth of the finch beaks is higher in the finches that survived the drought?

6. If the finches that survived the drought reproduced, make a prediction about what the distribution of beak

depths of the offspring would look like. How would this compare to the beak depth of the offspring that were

hatched before the drought?

38

7. The figure below shows the distribution of beak depths of fully grown offspring hatched in 1976 and 1978.

Explain how the difference in means of these two graphs (the birds hatched before the drought in 1976 and the birds

hatched in 1978) is a measure of evolutionary change between generations. Your response should reflect the four

factors of natural selection (learning target #1).

39

Natural Selection in Bacteria: Antibiotic Resistance

Antibiotic Resistance: http://outreach.mcb.harvard.edu/animations/resistance7.swf

Go through the tutorial and answer the following questions:

1. Describe how the case study of antibiotic resistance in Mycobacterium tuberculosis is an example of evolution by

natural selection.

2. What environmental factors promote natural selection of antibiotic resistance in bacterial populations?

3. Why are antibiotic resistant bacteria a problem to people in society?

Consider that the process of evolution by natural selection primarily results from four factors:

i. The potential for a species to increase in number,

ii. The heritable genetic variation of individuals in species due to mutation and sexual reproduction,

iii. Competition for limited resources, and

iv. The proliferation of those organisms that are better able to survive and reproduce in the

environment.

4. Explain how antibiotic resistant bacteria meet each of the four factors.

I.

II.

III.

IV.

40

http://outreach.mcb.harvard.edu/animations/resistance7.swf

http://outreach.mcb.harvard.edu/animations/resistance7.swf

Population Genetics Lab: Fishy Frequencies Understanding natural selection can be confusing and difficult. People often think that animals consciously adapt to their environments - that the peppered moth can change its color, the giraffe can permanently stretch its neck, and the polar bear can turn itself white - all so that they can better survive in their environments. In this lab you will use brown and yellow goldfish crackers to help further your understanding of natural selection and the role of genetics and gene frequencies in evolution. Background: Facts about the “Fish”

● These little fish are the natural prey of the terrible fish-eating sharks - YOU! ● Fish come with two phenotypes – brown and yellow

○ brown: this is a recessive trait (bb) ○ yellow: this is a dominant trait (B_)

● In the first simulation, you, the terrible fish-eating shark, will randomly eat whatever color fish you first come in contact with. (There will be no selection.)

● In the second simulation, you will prefer to eat the brown fish (these fish taste yummy and are easy to catch) you will eat ONLY brown fish unless none are available in which case you resort to eating yellow fish in order to stay alive (the yellow fish taste salty, are sneaky and hard to catch).

● New fish are born every “year”; the birth rate equals the death rate. You simulate births by reaching into the pool of “spare fish” and selecting randomly.

● Since the brown trait is recessive, the brown fish are homozygous recessive (bb). Because the yellow trait is dominant, the yellow fish are either homozygous or heterozygous dominant (BB or Bb).

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. This also allows you to figure out the frequency of genotypes from phenotypes. You assume that in the total population of goldfish, you have the following genotypes, BB, Bb, and bb. You also assume that mating is random so that ff could mate with bb, Bb, or BB; or Bb could mate with bb, Bb, or BB, etc. In addition, you assume that for the brown and yellow traits there are only two alleles in the population: B and b. If you counted all the alleles for these traits, the fraction of “b” alleles plus the fraction of “B” alleles would add up to 1.

The Hardy-Weinberg equation states that: p2 + 2pq + q2 = 1 This means that the fraction of pp (or BB) individuals plus the fraction of pq (or Bb) individuals plus the fraction of qq (bb) individuals equals 1. The pq is multiplied by 2 because there are two ways to get that combination. You can get “B” from the male and “b” from the female OR “b” from the male and “B” from female. If you know that you have 16% recessive fish (bb), then your qq or q2 value is .16 and q = the square root of .16 or .4; thus the frequency of your f allele is .4 and since the sum of the b and B alleles must be 1, the frequency of your B allele must be .6 Using Hardy Weinberg, you can assume that in your population you have .36 BB (.6 x .6) and .48 Bb (2 x .4 x .6) as well as the original .16 bb that you counted.

51

Simulation 1: Without Selection…Small Population 1. Get a random population of 10 fish from the “ocean.” 2. Count brown and yellow fish and record in your chart; you can calculate frequencies later. 3. Eat 3 fish, chosen randomly, without looking at the plate of 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 brown and yellow fish. 6. Again eat 3 fish, randomly chosen. 7. Add 3 randomly selected fish, one for each death. 8. Count and record. 9. Repeat steps 6, 7, and 8 two more times.

Simulation 2: With Selection…Small Population 1. Get a random population of 10 fish from the “ocean.” 2. Count brown and yellow fish and record in your chart; you can calculate frequencies later. 3. Eat 3 brown fish; if you do not have 3 brown fish, fill in the missing number by eating yellow 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 brown and yellow fish. 6. Again eat 3 fish, all brown if possible. 7. Add 3 randomly selected fish, one for each death. 8. Count and record. 9. Repeat steps 6, 7, and 8 two more times.

Data:

Table 1: Without Selection…Small Population

Generation Brown Yellow q2 q p p2 2pq

1

2

3

4

5

Table 2: With Selection…Small Population

Generation Brown Yellow q2 q p p2 2pq

1

2

3

4

5

52

Analysis: 1. Construct one graph, using both sets of data (without selection AND with selection). On the “x” axis put generations 1-5 and on the “y” axis put frequency (0-1). Plot both the q and p for both sets of data. Label lines clearly (without selection AND with selection) – don’t forget a title. Title: _______________________________________________________________________________________________

KEY: ⬜ ⬜ ⬜ ⬜

53

2. In either simulation, did your allele frequencies stay approximately the same over time? If yes, which situation? What conditions would have to exist for the frequencies to stay the same over time? 3. Compare your data to another group or to the class. Is your data different? How? Why is it important to collect class data? 4. With selection, what happens to the allele frequencies from generation 1 to generation 5? 5. What process is occurring when there is a change in allele frequencies over a long period of time? 6. What would happen if it were more advantageous to be heterozygous (Bb)? Would there still be homozygous fish? Explain. 7. In simulation 2, what happens to the recessive alleles over successive generations and why? Why don’t the recessive alleles disappear from the population? 8. Explain what would happen if selective pressure changed and the recessive allele was selected FOR? 9. What happens if the sharks only eat very large fish that have already reproduced? What happens if they eat small brown fish, before they have a chance to reproduce? 10. In what ways did these simulations represent real life? How were the simulations different from real life situations?

54

A Step in Speciation: Ensatina Salamanders

Pre Activity Questions

1. What is reproductive isolation? Why is it important to speciation?

2. Define and give example of the following reproductive isolating mechanisms.

Pre-zygotic Mechanisms - isolate two populations without zygotes forming

Temporal isolation –

Behavior isolation –

Habitat isolation –

Mechanical isolation –

Gametic Isolation –

Post-zygotic Mechanisms – isolate two populations when zygotes form

Hybrid Inviability –

Hybrid Infertility –

Hybrid Breakdown –

3. How does geographic isolation lead to speciation? How do you know when two or more populations have become

distinct species?

55

Background

When Darwin wrote On the Origin of Species , he believed that speciation, working through the mechanism of natural

selection, was too gradual to be witnessed and could only be inferred from the fossil record, the distribution of similar

species, and such. In the 1950’s R.C. Stebbins, at the University of California at Berkeley, completed a study on the

salamanders in the genus Ensatina , thought at the time to consist of four species.

Salamanders in the genus Ensatina are plethodontid salamanders that inhabit the terrestrial coniferous forests and

oak woodlands from southern British Columbia in Canada, along the coast, to northern Baja, California. Their range

extends east to the western slopes of the Cascades, Sierra Nevada, and Peninsular mountain ranges. Stebbins

interest in these salamanders arose from observation of patterns existing in separate populations of these

salamanders. Stebbins wondered if there were in fact four species, and if a speciation event was being observed in

these salamanders.

At the time, species had been defined by Ernst Mayr as “groups of actually or potentially interbreeding natural

populations that are reproductively isolated from other such groups”. Difficulties arise when a species has a large

range and appears to be segregated into distinct populations based on their location and the visible variations

existing between populations. In such situations, the separate populations may be considered “subspecies”,

suggesting that they may be on a trajectory leading them to become distinct species. Unlike the binomials given by

Carl Linnaeus, subspecies names contain three words (i.e. Homo sapiens neanderthal ).

In the following activity, you will simulate observes of the populations of the Ensatina salamanders that Stebbins

made in the 1950’s, analyze his and others data, and make conclusions on speciation in these salamanders.

Procedure

1. Watch the video clip: http://www.pbs.org/wgbh/nova/evolution/evolution-action-salamanders.html

2. Imagine that you are working with Stebbins' salamander specimens, some of which are pictured on the

colored sheets provided.

3. In the list below, salamander collections are identified by the letters a-g. These letters correspond to pictures

of salamanders you have been given.

a. Ensatina 1 (15; brown): 32/R, 32/S, 30/T, 31/T

b. Ensatina 2 (203; red): 30/M, 32/O, 34/S, 35/V, 36/W, 35/Z, 38/Y, 40/Z

c. Ensatina 3 (48; blue): 36/Z, 38/a, 39/a, 40/a

d. Ensatina 4 (373; purple): 9/B, 7/E, 6/E, 13/C, 10/C, 7/D, 15/D

e. Ensatina 5 (230; yellow): 2/B, 2/C, 3/C, 4/C

f. Ensatina 6 (120; green): 8/J, 10/J, 11/M, 13/M, 15/M, 15/O, 17/M, 15/P, 20/Q, 24/S, 21/R, 25/T, 26/U

g. Ensatina 7 (271; orange): 17/G, 17/F, 19/H, 19/O, 20/I, 20/J, 21/I

a. The parentheses after each subspecies name contain a number and a color. The number is the total

of individuals Stebbins had available for his study. The color is the one you should use for that

collection when you plot its collection area on the California map.

b. Following the parentheses is a list of grid codes indicating where (on the map grid) the subspecies was

collected. For example, 32/R means that one or more specimens were collected near the intersection

of horizontal Line 32 and vertical Line R.

c. Plot each collection area by filling in the corresponding square on the California map grid. Color in the

square above and to the left of the point where the specified grid coordinates cross. For example, the

square in the upper left-hand corner is 1/A. Use the colors indicated for each subspecies population

(listed above) to make a distribution map of Ensatina complex in California.

56

http://www.pbs.org/wgbh/nova/evolution/evolution-action-salamanders.html

http://www.pbs.org/wgbh/nova/evolution/evolution-action-salamanders.html

4. Cut out the pictures of the salamanders and arrange them on the map in their appropriate locations.

Questions

1. Is the species uniformly distributed? Use your knowledge of the species’ ecological requirements to offer an

explanation of its distribution. What other factors might affect distribution?

2. Consider the physiography of California. Does the species seem more characteristic of mountain areas or of

valley areas? Justify your response.

3. Based on the information above and your knowledge of natural selection, explain why the Ensatina

salamanders appear the way they do (both the coastal and more eastern populations). Be as specific as you

can in applying the principles of natural selection.

4. How many distinct populations can you observe based on the location of the specimens (disregard the colors

for the time being)? Which colored populations appear to be single population? Explain.

5. In a brief paragraph, explain why Stebbins concluded that there is only one species of Ensatina in California.

57

Pollenpeeper Speciation Lab

Introduction:

As natural selection acts upon the variations present in a population, certain phenotypes are favored in terms of

survival and, more importantly, their ability to reproduce. This variance in the rate of reproduction, called differential

reproduction, is the driving force behind the changes observed in populations. This differential reproduction may

ultimately lead to variances between members of a population that are so great that it prevents them from being able

to reproduce with other members of their population. If these organisms can only mate with other organisms like

them (who are drastically different from the rest of the population), they may become so distant as to become a new

species.

There are several modes of speciation:

● Geographic Isolation

○ Allopatric Speciation : a population becomes separated by an actual physical barrier that gets

between members of a population. An example would be the isolation of different tortoises on the

various Galápagos’ Islands, leading to divergence in shells.

○ Peripatric Speciation : a few individuals of a population are isolated, perhaps by some sort of disaster

that kills off all but a few of the isolated population. An example of peripatric speciation is the London

Underground mosquito. As a result of its isolation in the London subways, this small population of

mosquitos became less tolerant of cold and lost the behaviors that made it able to mate with its

normal population.

● Reproductive Isolation

○ Sympatric Speciation : populations are not isolated at all and live in the “same place.” An example of

sympatric speciation would be the Hawthorn Fly, some of which have evolved the preference for

developing their maggots in apples as opposed to their normal host, the Hawthorn.

Purpose: In this lab, you will be observing a simulation of speciation similar to that noted by Charles Darwin in regard

to the finches of the genus Geospiza. You will be tracking the phenotypic changes in populations of a hypothetical

genus of bird, the pollenpeeper (modeled on the divergence of the Hawaiian honeycreeper into 57 different

61

varieties). Your job will be to assess and explain the various selective pressures that must have been influencing the

changes seen in each population over the course of five million years.

Procedure:

1) Access the website: http://www.pbs.org/wgbh/evolution/darwin/origin/

2) Click through to the following screen containing the map of the pollenpeeper habitats

3) Click on the detailed view for the mainland. Here you will see descriptions of the events, habitat parameters (i.e.

food, level of competition), geographic distribution and phenotypic changes in the populations of pollenpeepers at

this location. In the space below, take notes on the major changes observed for this location.

4) Click forward on the timeline at the bottom to move forward from 5 mya to the present. You may also click on the

blue bar just above it for a more detailed explanation of the events at each interval

5) Repeat this process for Norcross, Warwick and Windsor.

Notes:

Mainland Competition Habitat Food Predators

5mya

4mya

3mya

2mya

1mya

Present

62

http://www.pbs.org/wgbh/evolution/darwin/origin/%20

http://www.pbs.org/wgbh/evolution/darwin/origin/%20

Windsor Competition Habitat Food Predators

5mya

4mya

3mya

2mya

1mya

Present

63

Norcross Competition Habitat Food Predators

5mya

4mya

3mya

2mya

1mya

Present

64

Warwick Competition Habitat Food Predators

5mya

4mya

3mya

2mya

1mya

Present

65

Analysis Questions: Use your notes to answer the following questions, citing specific details and dates in support of

your answers.

Mainland Population

#1) What phenotype(s) tended to become most frequent in the mainland over the course of 5 million years?

#2) Which biotic and abiotic selective pressures do you feel are most responsible for these changes? Why?

#3) Which mode of speciation allopatric, peripatric or sympatric best describes the evolution of the phenotype you

noted in question #1? Support your answer.

Windsor Island

#4) What phenotype(s) tended to become most frequent on Windsor Island over the course of 5 million years?

#5) Which biotic and abiotic selective pressures do you feel are most responsible for these changes described in

question #4? Why?

#6) Which mode of speciation allopatric, peripatric or sympatric best describes the evolution of the phenotype you


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Norcross Island

#7) What phenotype(s) tended to become most frequent on Norcross Island over the course of 5 million years? Be

specific re: coastal and inland populations?


question #7? Why?

#9) Which mode of speciation allopatric, peripatric or sympatric best describes the evolution of the phenotypes you


#10) How do the changes in head plumage illustrate the concept of differential reproduction ?

Warwick Archipelago

#11) What phenotype(s) tended to become most frequent on Warwick Archipelago over the course of 5 million

years? Detail the major changes and when they happen.

Coastal

Lowland

Desert

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Forest


question #12? Why? Once again, subdivide your answer to address the changes that happen in the last two million

years.

Coastal

Lowland

Desert

Forest

#13) Which mode of speciation allopatric, peripatric or sympatric best describes the evolution of the phenotypes you


#14) How do the changes observed on Warwick illustrate the theme of continuity within change ?

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Speciation: The Utopian Islands

Imagine yourself traveling back in time 6 million years. At this point in history, volcanoes are spurting up from the floor of the Pacific Ocean, creating many new islands. You are transported to two of these islands, Utopia Major and Utopia Minor. Refer to the map of the islands below.

Follow the instructions below to complete your flow chart.

1. Some of the first inhabitants of Utopia Major are a group of flies, blown over on a strong wind from a nearby continent. They have large eyes, a large pair of clear wings, and can tolerate a temperature range from 60-90° F. Refer to the flow chart. The information about the island fly population is summarized in Box A.

2. Over the next few thousand years, the volcano on Utopia Major erupts many times. It gradually builds up a high ridge, dividing the island into north and south portions. The ridge is a permanent barrier. Fill in boxes B and C, showing the features of the two fly populations, north and south.

3. A mutation occurs in the northern population, producing some flies that can tolerate temperatures up to 105° F. Fill in boxes D and E, showing the features of the two northern fly populations.

4. The strong winds blow some flies from the southern group to the neighboring island, Utopia Minor. Fill in boxes F and G, showing the population left on the south side of Utopia Major and the new population of Utopia Minor.

5. A two-year period of heat waves reaching 102° F strikes the northern side of Utopia Major. Fill in box H with the surviving flies.

6. A mutation occurs in the Utopia Minor flies, creating striped wings on some of the male flies. Show the two northern fly populations in boxes I and J.

7. A mutation on the northern side of Utopia Major occurs, causing some flies to have white eyes. Show the two northern fly populations in boxes K and L.

8. Back on Utopia Minor, a strange behavior is happening. Female flies all seem to prefer the stripe-winged males and never mate with the clear-winged males. Show the surviving population of male flies on Utopia Minor in box M.

9. Back on Utopia Major, a new species of fly-eating birds colonizes the northern section of the island. They never cross to the south side and eat any red-eyed flies they can find. Show the surviving population of the northern flies in box N.

10. The southern flies on Utopia Major have remained unchanged after all these years. Show the modern population of southern flies in box O.

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Analysis Questions

1. Using the key at the bottom of the flow chart to help you, classify the factors that influenced the speciation of

the fly populations in the columns below.

Abiotic Events Mutations Selection Events

a. a. a.

b. b. b.

c. c.

2. How many distinctly different groups of flies now inhibit the Utopian Islands? Do you think they are actively

breeding with each other? Give evidence from your flow chart and map to support your answer.

3. A scientist studying the islands hypothesizes that the surviving groups of flies are now separate species. How

could he test his hypothesis? (Hint: look at your notes and what defines a species).

4. Complete the table below by suggesting an event for each row and how they could impact the flies in the

future, possibly causing new species to form.

Description of Event Immediate Effect on Flies How this can lead to speciation (long term effect)

Abiotic Event:

Mutation:

Selection Event:

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Unit 6 Reflection

A. How does each lab/activity exemplify the learning targets for the unit? Don’t discuss what you learned

in this part, but instead be specific about each learning target that was met. Use the dos and don’ts

suggestions and previous feedback to help you!

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B. What were you able to learn by completing the labs/activities? Again, be specific about each learning

target and how each lab you selected helped you learn that learning target. Use the dos and don’ts

suggestions and previous feedback to help you!

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C. How did the labs/activities compare and contrast to each other? Use a graphic organizer (Venn diagram,

t-chart, etc) to demonstrate your thorough understanding of how the labs compare/contrast. Again, be

specific and use the dos and don’ts suggestions!

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D. In which labs during the unit did you experience trouble? This includes ANY lab in the unit, not just the 3

you selected. Again, be specific and use the dos and don’ts suggestions!

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E. How does this unit of work relate to real life situations? Again, be specific and use the dos and don’ts

suggestions!

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Article Rationale & Summary

Article Title: ____________________________________________________________________________

Author(s): _____________________________________________________________________________

Source: ________________________________________________________________________________

Summary: Summarize the main points of the article in 4-6 sentences.

Rationale for inclusion in this unit: How does the material in the article relate to what was learned/studied in

this unit? Include a detailed description of at least 3 different specific examples. Again, be specific about each

connection and use the dos and don’ts suggestions!

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(Copy of Article)

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Personal Choice

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Rationale for Personal Choice

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