Scientists, Wolves and the United States Government – Grade 10
Ohio Standards
Connection:
Life Sciences
Benchmark H
Describe a foundation of
biological evolution as the
change in gene frequency
of a population over time.
Explain the historical and
current scientific
developments, mechanisms
and processes of biological
evolution.
Indicator 21
Explain that natural
selection provides the
following mechanism for
evolution; undirected
variation in inherited
characteristics exist within
every species. These
characteristics may give
individuals an advantage or
disadvantage compared to
others in surviving and
reproducing. The
advantaged offspring are
more likely to survive and
reproduce. Therefore, the
proportion of individuals
that have advantageous
characteristics will
increase. When an
environment changes, the
survival value of some
inherited characteristics
may change.
Related Standard
Scientific Ways of
Knowing
Benchmark A
Explain that scientific
knowledge must be based
on evidence, be predictive,
logical, subject to
modification and limited to
the natural world.
Lesson Summary:
This lesson helps students see that scientists can examine
the same data and see different results. Students will use a
simulated electrophoresis gel to examine the DNA
fingerprints of the coyote, gray wolf and red wolf to
critically analyze the evolutionary history of these
organisms. Students will take on the role of scientist to
determine if the red wolf is a hybrid or a true species, and
interpret the conservation status of the red wolf using the
United States Endangered Species Act. Their efforts will
mirror those of scientists, as the equivocal data will not
solve the evolutionary relationship, or solve the endangered
status of the red wolf. Students will consider the
relationships of the coyote, red wolf and gray wolf using a
model of allopatric speciation to help them understand the
process of speciation. Finally, students will study how
speciation may occur without geographic isolation by
investigating sympatric speciation in the corn root worm.
Just as with the red wolf problem, students will try to
determine if the new strain of root worm should be
considered a species or a hybrid.
In this lesson, students will learn that there is often
conflicting data and no conclusions can be made until other
data are available. This exercise has no right answer,
except to understand that scientists always seek more
information and may disagree on the interpretation of that
data.
Estimated Duration: Three to five hours
Commentary:
This lesson helps students understand what it is like to
critically analyze evolutionary theory as they test the
evolutionary relationships of organisms and consider
models of evolutionary change. The data in this lesson will
lead to a variety of interpretations by the students. It is this
spirited discourse, or agreement to disagree, which
characterizes scientific endeavor. Using real-life examples,
students will get to think about the process of evolutionary
change and the kinds of data that can be gathered to test
their ideas. Cooperative learning groups are an integral part
of this lesson and an active exchange of ideas is
encouraged.
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Scientists, Wolves and the United States Government – Grade 10
Indicator 2
Describe that scientists
may disagree about
explanations of
phenomena, about
interpretation of data or
about the value of rival
theories, but they do agree
that questioning, response
to criticism and open
communication are integral
to the process of science.
Indicator 3
Recognize that science is a
systematic method of
continuing investigation,
based on observation,
hypothesis testing,
measurement,
experimentation, and
theory building, which
leads to more adequate
explanations of natural
phenomena.
Pre-Assessment:
 Scientists often re-examine data to determine if a group of
organisms falls within the scientific and legal definition of
a species. The red wolf is an excellent organism to study
to see how scientists may look at the same data and come
to different conclusions about its evolutionary history.
Read the following account, or print and pass out for
students to read.
The Endangered Species Act (ESA), passed by the United
States Congress, mandates that the government protect species
that are in danger of extinction. In 1970, there were fewer
than 100 red wolves in existence making them candidates for
protection. In 1851, John James Aududon named a small
reddish wolf Canis rufus. The United States also is home to
two other wild members of the genus Canis, the gray wolf,
Canis lupus, and the coyote, Canis latrans. The red wolf falls
between these two organisms in size. It is larger than a coyote
but smaller than a gray wolf. This has led scientists to wonder
about the identity of the red wolf. Is the red wolf a “true”
species or something else? Has the red wolf been around a
long time or is it a recent organism?

Pose the following questions to students and have them
write their answers on a sheet of paper.
1. What is a species?
2. What characteristics of an organism would scientists
examine to see if that animal was a hybrid or a unique
species?
3. How might scientists argue that the red wolf is not a
species?
Scoring Guidelines:
Acceptable answers include, but are not limited to, the
following responses.
1. A species is a group of actually or potentially
interbreeding organisms that is not capable of successfully
interbreeding with other interbreeding groups of
organisms.
2. Scientists could examine DNA, polymorphic body parts,
behaviors or breeding experiments to determine if the red
wolf is a species. For the red wolf to be a true species, it
must:
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Scientists, Wolves and the United States Government – Grade 10




Be part of an interbreeding population in nature;
Be able to produce fertile offspring;
Have DNA which is similar to other members of the proposed species;
Not be able to interbreed with similar species.
3. The student may illustrate one or more of the following points:
 If the red wolf contains some DNA similar to wolves and coyotes, it could be a
hybrid;
 Since the coyote has become more numerous and the red wolf more scarce, some red
wolves may have mated with coyotes;
 Wolves and coyotes may have been together in the distant past and produced the red
wolf then and not recently;
 Red wolves have a unique DNA not found in wolves or coyotes;
 Red wolves were found in areas where coyotes and gray wolves were not found;
 Red wolves were part of an interbreeding population.
Post-Assessment:
Pose the following questions to students and have them answer the questions on a sheet of
paper.
1. What characteristics of an organism would scientists examine to see if that animal was a
hybrid or a unique species?
2. Why do different scientists have different hypotheses of how the red wolf evolved?
3. Describe how allopatric speciation works.
4. Why don't scientists all agree that geographical isolation is required for the formation of
new species through natural selection or genetic drift?
5. Describe how scientists continue to investigate and critically analyze aspects of
evolutionary theory.
Scoring Guidelines:
Acceptable answers include, but are not limited to, the following responses.
1. Student shows one or more of the following points:
 The organism must be part of an interbreeding population in nature;
 It must be able to produce fertile offspring;
 It must have DNA, which is similar to other members of the proposed species and
different from other similar species;
 There should be some mechanism that prevents it from interbreeding with similar
species;
 The scientist could study a range of heritable body part shapes, such as number or
shape of teeth.
2. The data are equivocal. The genetic data may support a hybrid origin of the red wolf, the
red wolf may be an ancestor of the gray wolf and coyote, or the red wolf may be a sister
species to the gray wolf.
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3. Allopatric speciation requires a geographic barrier to dispersal between populations of an
organism. Genetic isolation over time leads to the accumulation of genetic mutations,
which may or may not cause reproductive isolation.
4. Speciation may occur without geographic isolation of populations. Temporal isolation, as
is observed in the corn root worm, may suffice to isolate populations. This isolation may,
in turn, facilitate genetic divergence.
5. The student explains one or more of the following points:
 Scientists can look at the same data and, based upon their own background, form an
opinion about an event.
 Scientists critically analyze the data. Sometimes they are able to reach a consensus.
There are times when scientists interpret the data differently and that is acceptable.
(Some scientists believe that Alzheimer's Disease may be triggered by a pathogen,
while others do not). Scientists keep studying problems, in this case, the evolution of
the red wolf.
Instructional Procedures:
Engage
1. Conduct the pre-assessment. Ideally, you will have photographs or species accounts of
the red wolf, gray wolf and coyote available to help pique student interest.
2. Discuss answers to the pre-assessment. Lead a class discussion clarifying the definitions
of species and hybrid. It is important to help students understand that the biological
species definition is based on the premise that a species can not breed with any other
species to produce offspring that are fit. Hybrids, on the other hand, can produce
offspring, but these offspring are typically not as viable and/or fit as the parent species
that produced them. Ideally, students will have encountered these concepts before this
lesson.
3. On the board or on an overhead, list characteristics of organisms which students think
would be helpful for determining if an organism is a species or a hybrid. Make sure that
DNA is in the list. Also list student ideas about why the red wolf may not be considered a
species.
Explore
4. Introduce the United States Endangered Species Act, ESA, to the class. It is important to
help students understand that this act protects species, but not hybrids, unless the hybrids
constitute a self-sustaining species.
Instructional Tip:
For background information about the ESA, go to the Web site for the United States Fish and
Wildlife Service and navigate to the link entitled ESA.
5. If students do not have background in DNA fingerprinting, introduce them to the basics
so that they understand how to interpret a banding pattern on an electrophoresis gel.
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Scientists, Wolves and the United States Government – Grade 10
Instructional Tip:
For background information about DNA fingerprinting, go to the Web site for the National
Biological Information Infrastructure and navigate to Biological Disciplines link, then
Genetic Biodiversity. Additional Information on DNA fingerprinting may be found at The
Queensland (Australia) Government Web site, under the topic of Beef Genetics.
6. Divide students into groups of two to four individuals. Be sure to follow standard
guidelines for cooperative learning. Students should record comments made by members
of the group.
7. Print copies of Attachment A, DNA Fingerprints, and cut the fingerprints for gray wolf,
coyote and red wolf into separate strips of paper. Give half of the students in a group the
simulated DNA fingerprint of Canus lupus, the gray wolf. Give the other half of the
group the simulated DNA fingerprint of the coyote, Canis latrans. Instruct students to
examine the DNA fingerprint they have and then compare and contrast the two. Make
sure that students line up the fingerprints using the alignment line.
8. Give each group the simulated DNA fingerprint of the red wolf Canus rufus. Have
students compare and contrast the fingerprint of the red wolf with that of the coyote and
gray wolf. Make sure that students use the alignment line on Attachment A, DNA
Fingerprints. Students can use Attachment B, Worksheet, to record their observations and
conclusions. The attachment includes some questions that may guide students.
9. Have each group come to a consensus about the genetic relationship of the red wolf to the
gray wolf and coyote. The fingerprint in Attachment A, DNA Fingerprints does not
clearly delineate relationships among these three organisms, so student groups may arrive
at a variety of interpretations. See Attachment C, DNA Fingerprint Analysis, for an
interpretation of the banding pattern. See Attachment D, Worksheet Answers, to help
guide student work on their worksheets.
10. Instruct each group to come to a consensus about the legal status of Canus rufus or the
red wolf. The possibilities are:
 Canus rufus is a true species and should be protected.
 Canus rufus is a hybrid between the gray wolf and the coyote and should not be
protected.
 If Canus rufus is a hybrid which of the following applies?
 Canus rufus is a hybrid that evolved fairly recently (some data suggests the last 200
years) and should not be protected.
 Canus rufus is a hybrid that evolved a long time ago (some data suggests 700,000
years ago) and should be protected.
 Canus rufus is the ancestor of both gray wolves and coyotes and should be protected.
 Canus rufus is the ancestor of coyotes and some extinct wolf and should be protected.
 There simply is not enough information available to make a sound judgment about
Canus rufus.
11. After each group reaches some form of closure, have each group report to the class on its
conclusion. Record each group’s conclusion on the board and determine if there is a class
consensus. Point out that this topic is currently debated among biologists. Some are
convinced by looking at the data that the red wolf is a hybrid and no more money should
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Scientists, Wolves and the United States Government – Grade 10
be spent on preserving it. Another group is convinced by looking at the same data that the
red wolf is the ancestor of coyotes and possibly other wolves and should be protected.
Others are researching the Eastern Canadian wolf and feel it also is a red wolf, and that
the red wolf is the ancestor of the southern U.S. red wolf and the Eastern Canadian wolf.
12. Point out that most research creates more questions and scientists rarely learn all the
answers.
Explain
13. Tell the students that they are going to learn more about speciation and hybridization.
14. Have each group of students consider (or find) two very similar organisms that they think
represent different species.
Instructional Tip:
You may want to have students take a brief field trip outside where they may collect different
leaves (oak and maple, or white oak versus black oak). Students might use field guides
(available in libraries) to pick two similar species of flower, insect or bird. Students in
agricultural areas could cite the differences between wheat and oats. Hunters, birdwatchers
and other outdoor enthusiasts could cite differences between fish species or game such as
gray versus red squirrels, or Canadian goose versus snow goose.
15. Ask groups of students to answer the following questions on a sheet of paper.
a. How can you tell they are different species?
b. How do you suppose they can tell they are different species?
c. If two species do not recognize each other as different species, how do they remain
different species?
16. Discuss answers to questions as a class. Use the following guidelines for discussion.
a. Students will typically recognize different species by appearance. They may also
recognize species by behaviors such as calls, flight patterns or diet.
b. Students will cite the same characteristics as they did for their answers to the first
question. Answers may include more communication/ behavioral characteristics ("the
animals tell each other that they are different").
c. Students may already know about pre- and post-mating isolating mechanisms. These
are mechanisms that prevent species or incipient species from mating with one
another. Pre-mating mechanisms prevent mating and include physical barriers to
reproduction, behavioral mechanisms that prevent communication between potential
mates, and temporal mechanisms which find different species mating at different
times. Post-mating mechanisms occur after mating and preclude fertilization, prevent
development of hybrid organisms, or prohibit successful reproduction by surviving
hybrids. For example, a number of organisms that are assigned to different genera
have successfully mated and produced offspring. Examples are king snakes
(Lampropeltis) with gopher snakes (Pituophis), Corn snakes (Elaphe) with king
snakes, and lions with tigers. However, these hybrids have lowered fertility and/or are
sterile.
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Scientists, Wolves and the United States Government – Grade 10
Instructional Tip:
Refer to the Web site for the National Biological Information Infrastructure to help students
learn about speciation and hybridization. Follow the link to Biological Disciplines, choose
the link to Genetic Biodiversity, and then the link entitled Introduction to Genetic Diversity.
17. Provide students with Attachment E, Allopatric Speciation Model, and discuss how this
model represents the commonly-accepted theory for the formation of new species. It
suggests that individuals in a single population of interbreeding organisms must become
isolated into two or more separate populations over a long period of time. These separate
populations then experience the effects of evolutionary processes (natural selection,
genetic drift, gene flow, mutation), which results in the accumulation of genetic
differences. These genetic differences sometimes result in the development of new
species (pre- and post-mating isolating mechanisms).
18. During your explanation of allopatric speciation, ask students to share their ideas about
things that could serve as geographic barriers to breeding between populations. For
example, plants or animals may be isolated by rivers, canyons, continents drifting away,
highways, volcanic islands or habitat. The squirrels on the north and south rims of the
Grand Canyon are an example. There are mice found in Kentucky that are not found in
Ohio; the Ohio River blocks them.
19. Have student groups draw models similar to Attachment E, Allopatric Speciation Model,
to explain the species and/or hybrid relationships that they posed for the red wolf to the
gray wolf and coyote. Attachments F, G, H and I show the Allopatric Speciation Model
adapted to four plausible explanations for the relationship among these organisms.
Instructional Tip:
Show students that a hybrid would be represented as a circle between two species with
arrows between the species and the hybrid population. See Attachments F and G.
Expand/Elaborate
20. Discuss group representations of the allopatric species model to help dispel
misconceptions about speciation and hybridization.
21. Suggest to students that since they understand allopatric speciation, they can now
consider a more conceptually difficult case of speciation. This case will be about the corn
root worm, which is a common pest in Ohio. A visit from a county extension agent or a
conversation about Ohio's agricultural economy, could prove stimulating to students.
22. Provide students with Attachment J, Corn Rootworm Adaptation, and present the
information or allow students to read on their own.
23. Divide students into cooperative groups and have them come to consensus answers to the
following questions:
a. Is the population of the corn rootworm, which is adapted to crop rotation, a new
species?
b. How can you tell if it is a new species?
c. If the resistant population of corn root worm is a new species, how was this speciation
different than the allopatric speciation that you have just studied?
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Scientists, Wolves and the United States Government – Grade 10
Instructional Tip:
For a fact sheet about corn root worm and its adaptation to crop rotation in Ohio, refer to the
Ohio State University's OhioLine Web site. Link to Fact Sheets, followed by Entomology
Series, and then Corn Rootworm Management.
24. Lead a class discussion of the questions and the answers that the students have
developed.
Possible answers:
a. We cannot tell with the given information if it is a new species. If they do not breed
with the rest of the corn root worms, then it is a new species.
b. If it breeds with the regular corn root worm, then it is a species. We may be able to
tell by assessing genetic fingerprints like we did with the wolf data. The corn root
worm population may be an example of speciation in progress, so we may see some
slow differentiation between populations accompanied by reduced interbreeding.
c. If we are observing speciation, it is not by geographic isolation. Isolation is instead
mediated by temporal isolation of populations. This is similar to the isolation and
genetic divergence that we see occurring among populations of periodic cicadas.
25. Point out that the students have just considered another aspect of evolutionary theory that
scientists critically analyze; sympatric speciation. This type of speciation can apparently
occur without the geographic isolation that we see in allopatric speciation.
Differentiated Instructional Support:
Instruction is differentiated according to learner needs to help all learners either meet the
intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the
specified indicator(s).
 For the red wolf exercise, students could be given the chart with a straw section or some
raised item on the simulated DNA chart to provide tactile representation.
Extensions:
 Have students with Internet access search the Web for information about the status of the
red wolf and the controversy about whether it is a species and should be protected, or a
hybrid and allowed to go extinct.
 While studying the red wolf problem, allow groups to represent various interest groups
such as:
a. Individuals who want the red wolves protected and reintroduced into the wild;
b. Individuals who do not want to spend any money on red wolves;
c. Individuals who do not want the wolves released into the wild but think they should
be protected;
d. The United States Fish and Wildlife Service that must hold public hearings on this
matter and follow the Endangered Species Act.
 A public hearing could be held with the different groups expressing their feelings about
the red wolf with or without data to back them up.
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Scientists, Wolves and the United States Government – Grade 10

Other areas where scientists are still unsure of the evolutionary relationships or how
specific organisms evolved (evolutionary theory) could be examined such as:
a. Domestication of domestic animals;
b. Birds and dinosaurs;
c. Flight in insects;
d. Colonial organisms or what constitutes an organism;
e. Algae and fungi relationships in lichens;
f. Apple maggot fly.
Homework Options and Home Connections:
Have students conduct an Internet search for research projects that scientists are currently
conducting. Ideally, students will search for types of evolutionary research that are currently
being done. Have the students identify the area of evolutionary theory that is being critically
analyzed by the work.
Materials and Resources:
The inclusion of a specific resource in any lesson formulated by the Ohio Department of
Education should not be interpreted as an endorsement of that particular resource, or any of
its contents, by the Ohio Department of Education. The Ohio Department of Education does
not endorse any particular resource. The Web addresses listed are for a given site’s main
page, therefore, it may be necessary to search within that site to find the specific information
required for a given lesson. Please note that information published on the Internet changes
over time, therefore the links provided may no longer contain the specific information related
to a given lesson. Teachers are advised to preview all sites before using them with students.
For the teacher: Attachments.
For the students: Attachments.
Vocabulary:
 allopatric speciation
 diapause
 divergence
 dna fingerprint
 eclose
 electrophoresis
 gene flow
 genetic drift
 hybrid
 natural selection
 reproductive isolation
 species
 sympatric speciation
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
temporal isolation
Technology Connections:
 For background information about the Endangered Species Act, go to the Web site for the
United States Fish and Wildlife Service at www.fws.gov and navigate to the link entitled
ESA.
 For background information about DNA fingerprinting, go to the Web site for the
National Biological Information Infrastructure at www.nbii.gov and navigate to
Biological Disciplines link, and then Genetic Biodiversity. Additional Information on
DNA fingerprinting may be found at The Queensland (Australia) Government Web site
at www.dpi.qld.gov. under the topic of Beef Genetics.
 Refer to the Web site for the National Biological Information Infrastructure at
www.nbii.gov to help students learn about speciation and hybridization. Follow the link
to Biological Disciplines, and then choose the link to Genetic Biodiversity.
 For a fact sheet about corn root worm and its adaptation to crop rotation in Ohio, refer to
the Ohio State University's OhioLine Web site at http://ohioline.osu.edu and link to Fact
Sheets.
Research Connections:
Marzano, R. et al. Classroom Instruction that Works: Research-Based Strategies for
Increasing Student Achievement. Alexandria: Association for Supervision and Curriculum
Development, 2001.
Identifying similarities and differences enhances students’ understanding of and ability to
use knowledge. This process includes comparing, classifying, creating metaphors and
creating analogies. This process may involve the following:
 Asking students to independently identify similarities and differences;
 Representing similarities and differences in graphic or symbolic form.
Nonlinguistic representations or imagery mode help students think about and recall
knowledge. This includes the following:
 Creating graphic representations (organizers);
 Generating mental pictures;
 Drawing pictures and pictographs.
Cooperative learning grouping has a powerful effect on student learning. This type of
grouping includes the following elements:
 Positive interdependence;
 Face-to-face promotive interaction;
 Individual and group accountability;
 Interpersonal and small group skills;
 Group processing.
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Cues, questions and advanced organizers help students retrieve what they already know
about a topic. Activating prior knowledge is critical to learning new concepts.
General Tips:
 This lesson should come after students understand biological classification, and how
classifications reflect evolutionary relationships.
 The purpose of this lesson is to show that scientists don’t always agree and most often
more research is done.
Attachments:
Attachment A, DNA Fingerprint
Attachment B, Worksheet
Attachment C, DNA Fingerprint Analysis
Attachment D, Worksheet Answers
Attachment E, Allopatric Speciation Model
Attachment F, Allopatric Speciation with Red Wolf as Modern Hybrid
Attachment G, Allopatric Speciation with Red Wolf as Historic Hybrid, with no Modern
Hybridization Occurring
Attachment H, Allopatric Speciation, With Red Wolf and Gray Wolf from a Common
Ancestor
Attachment I, Allopatric Speciation, With Red Wolf as Ancestor of Gray Wolf and Coyote
Attachment J, Corn Rootworm Adaptation
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Attachment A
DNA Fingerprint
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Attachment B
Worksheet
Name _____________________________
Data worksheet for gray wolf/Canis lupus;coyote/Canis latrans; red wolf/Canis rufus.
1. What similarities are found between gray wolves and coyotes?
2. Explain why this may or may not be reasonable.
3. What similarities or differences did you find between the red wolf, coyote and gray wolf?
4. In determining the legal status, what factors led you to either protect or not protect the red
wolf?
5. What data would be important in making a final determination about whether the red wolf
is a species or a hybrid?
6. Describe why different scientists may disagree about the evolutionary history of the red
wolf.
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Attachment C
DNA Fingerprint Analysis
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Attachment D
Worksheet Answers
1. DNA at sites 1, 4, 7 and 8 are exactly the same. (Sites can be underlined and numbered.)
2.
Both organisms are closely related members of the Canus genus, so one would expect
the DNA to be similar.
3.
Sites 2, 10 and 13 were only found in red wolves, and sites 1, 4, 7 and 8 were the same
in all three. Site 6 was the same in the coyote and red wolf. Site 3 was the same in the
red and gray wolf.
4.
Answers may vary but should relate to the data.
5.
DNA from ancestor fossils, or old DNA from positively identified specimens, should be
examined. If the data is inconclusive, protect the red wolf until more data is available.
6. Scientists can look at the same data and have different interpretations. Scientists are
always looking for more data. When data supports one hypothesis, more research is
completed to confirm the results. If all research continues to support the hypothesis, the
hypothesis becomes a theory. Scientist continually analyze data to ensure the theory
holds true under various conditions.
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Attachment E
Allopatric Speciation Model
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Attachment F
Allopatric Speciation with Red Wolf as Modern Hybrid
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Attachment G
Allopatric Speciation with Red Wolf as Historic Hybrid
with no Modern Hybridization Occurring
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Attachment H
Allopatric Speciation With Red Wolf and
Gray Wolf from a Common Ancestor
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Attachment I
Allopatric Speciation With Red Wolf as Ancestor of Gray Wolf and Coyote
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Attachment J
Corn Rootworm Adaptation
Every major agricultural crop eventually becomes vulnerable to some kind of organism(s)
that we consider “pests” although biologically it might be more appropriate to consider them
competitors. In Ohio, corn contributes almost $1 billion in annual revenues. Not surprisingly,
corn pests/competitors must be taken seriously.
Many agricultural pests display a natural history trait such as over-wintering in the soil as a
pupa and emerging the next growing season into another corn crop planted in the same field.
One environmentally safe and economic weapon in Ohio corn growers' arsenal to fight such
pests is crop rotation: Corn is grown in a field one year and a different crop, often soybeans
(another billion dollar crop in Ohio), is grown in the same field the next year. Emerging corn
pests can’t eat soybeans just as soybean pests emerging in alternate years can’t eat corn
plants. Further, most corn and soy pests don’t fly far, if at all, making crop rotation even
more effective.
Alas, like any other method designed to combat crop pests/competitors, such efforts always
result in the development of resistance in the target pest. As far as farmers are concerned,
pest resistance is inevitable. If they weren’t competing with us for our food and livelihood,
we might call some instances of resistance brilliant; farmers consider them devious.
Corn root worm, a common and sometimes serious problem for Ohio corn growers, has
developed a number or resistance traits despite farmers’ attempts to control them. Perhaps the
most surprising is the development of a strain of rootworms that take two years to eclose
(emerge) as adults from the soil. This means they stay underground (extend their diapause
phase) as soybeans are grown in the field above them only to emerge the next year when corn
is grown in the field once again. This is an example of natural selection. The environment
(crop rotation) has selected for a population of root worm that stays underground until its
favored food is rotated into the field the next year. The insects have developed resistance to
crop rotation.
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