The hypothetical group of students reading this text set is in a high school introductory biology class, grades 9 or 10. This collection would be part of the ecology unit, learning about how animals have and how they affect each other and their environment. This could also be used in a conservation unit, as keystone species are often identified as important to conservation. The selections range from a broad overview as to what keystone species are, to examples of common keystone species, then to keystone species that could be found in our own backyard. The texts should be used together to relate a global phenomenon to local communities. The collection pieces come in three different formats, print, multimedia, and culturally relevant, with one example of each described in detail. During the lesson, I would start with the print text, to give an overview of what keystone species are, and then move into the video for a bit of history. Last, would be the culturally relevant text, so students are able to build on their prior knowledge with the new content.
Print
"Keystone Species." National Geographic. Ed. Jeannie
Evers. N.p., 29 June 2017. Web. Accessed 21 July 2017 at
<https://www.nationalgeographic.org/encyclopedia/keystone-species/>.
This text provides photos like the one below, as well as information in
textual format. This site gives a good overview definition and the official
classifications of keystone species, and briefly touches on a few examples of
keystone species, showing the variety of species in the world.
According to StoryToolz, the average
quantitative measurement for this text is grade 12. For the qualitative
measurements, the text structure is moderately complex. The text flows in an
organized manner, and the graphics are supplementary to understanding, and not
essential. Headings are given for each new topic, and help enhance the text
structure. The language features are very complex, with some words that might
be unfamiliar. Vocabulary terms that many need instructional support include
polyps, anthropogenic, autogenic and allogenic, niche, biodiversity, and tropic
cascade. The purpose is slightly complex, being clear, concrete, and narrowly
focused. The knowledge demands are moderately complex, because there are some
background knowledge demands, and simple abstract ideas.
Overall, while I agree that this is
a more difficult text, I think that it could be given to grades 9 or 10, not
just grade 12. There are many long sentences, and the information is dense, but
the words are familiar. The text is well organized, and has interesting stories
in it, so it is easy to read and follow. It focuses on many animal species that
students should already be familiar with, so there should be limited struggle
in relating to the text and using prior knowledge.
The purpose of this text is to
activate background knowledge of different species, and then to introduce the
topic of keystone species using animals and plants with which the students are
already familiar. Since this text is of medium complexity, it should have a
task also of medium complexity. It covers a wide range of species, so a text
organizer task like a concept map would be a good way to sort out the wide
variety of information. The center of the map would be on keystone species, and
the categories would be the different types mentioned in the article, such as
umbrella species or mutualists. The subcategories would then be examples of
these types of keystone species.
Wagner, S. C. (2010) Keystone Species. Nature Education Knowledge 3(10):51, accessed 20 July 2017 at <http://www.nature.com/scitable/knowledge/library/keystone-species-15786127>
This text gives the history of the term keystone species and the history
behind its discovery. It also lists several keystone species, and their roles
in their ecosystems. The article gives one very detailed example of the grey
wolf in Yellowstone National Park, and how its removal and revival have shaped
the whole area.
Multimedia
Jude Isabella, Adrienne Mason, “How Ecosystems Got a Keystone,” Hakai
Magazine, 6 Nov. 2015, accessed 23 July 2017 at <https://www.hakaimagazine.com/video/how-ecosystems-got-keystone>
Hakai Magazine provides a text in video format describing the discovery of
keystone species. The video is of Bob Paine, and he describes his experiment with
starfish that led him to the creation of the term “keystone species.” The video
includes the thought of ecology at the time, his research methods, and the
effects his research has had on the conservation of ecosystems. It also
provides a graphic of the effect of the removal of the starfish, and the
changes that happen with mussel growth and the loss of other resident species,
as shown in the food web below from nature.com.
StoryToolz gave this text a
quantitative average of 7.5. Qualitatively, the text structure is slightly
complex, as the organization is clear, and the graphics are helpful, but not
essential for understanding. The language features are also slightly complex
and are very conversational, with simple sentences and familiar language. There
are some terms that might not be new, but could benefit from instructional
support before or after the reading. These include experimental versus control,
core samples, Pisaster (the scientific name of the starfish), ecological
community, and observation versus experimentation. The purpose is slightly
complex as it is clear and concrete. The knowledge demands are moderately
complex, because knowledge of research methods would be necessary to fully
understand the video.
Overall, I would agree with the quantitative
measurement and give this text to students in grades 7 to 9. While the words
and story are simple to follow, background knowledge of the research process
and method are helpful in comprehension. The words may be easy to understand,
but the content is more complex.
The purpose of this text would be
to give information about the history of science and the term keystone species,
and to give an example of ecological keystone species research. As this text is
only slightly complex, I would choose a more complex task. I would have
students outline the text into the main parts of a research paper, the
background, methods, results, and discussion. This would familiarize my
students with both the content and the common way scientific results are
presented. This activity would demonstrate how keystone specie research is
conducted by true scientists, and show the students some of the nature of
science.
3 Animals That Keep Their Whole Ecosystem Together. Perf. Olivia
Gordon. SciShow, 30 Jan. 2017. Web, accessed 21 July 2017 at
<https://www.youtube.com/watch?v=JGcIp4YEKrc>.
This video gives a definition of keystone species, and describes in detail
the effects of the loss of these species through three examples, the grey
wolves, elephants, and parrotfish. The
examples include what happened when the grey wolf was removed from Yellowstone
National Park, and how that affected living things and even the rivers. The
video describes how the elephant shapes their ecosystem by knocking down large
trees, allowing young trees to grow, and lowering leaves to smaller animals,
and how even the elephant dung provides homes for species like frogs. The
parrotfish help to keep the coral reefs in balance by consuming organisms that
eat corals.
Culturally Relevant
"Coyotes." Milwaukee County Parks. N.p., n.d. Web,
accessed 23 July 2017 at <http://county.milwaukee.gov/Coyotes9205.htm>.
This article gives information about coyotes, a keystone species, found here
in Milwaukee County parks. It is a very informative page, giving information
about their appearance, habitat, diet, behavior, ecology, and diseases. It then
goes into recently spotted coyotes, what to do if you see one, and successful
ways to live peacefully with them.
Image from Wisconsin DNR 
StoryToolz gave this article a
quantitative score of grade 13. Qualitatively, the text structure is moderately
complex, as the text is organized well and the test features help enhance the
understanding of the content. The language features are very complex, with
dense information and complex sentences. There is also some difficult
vocabulary, such as extirpation, overabundant, inconspicuous, vaccinations,
secretions, reinforcement, languishing, coexistence, and encountering. The
purpose of this text is moderately complex, as it is implied but easy to
identify. The knowledge demands are slightly complex, as the subject matter is
common and there are simple, concrete ideas. Most students should be familiar
with coyotes and with the Milwaukee County parks. Overall, I would give the
text to grades 9 to 11, as although there are some complex words and sentences,
the content is very familiar and relatable.
The purpose of this text would be
to motivate interest in keystone species by demonstrating that they are right
in your neighborhood. While keystone species might seem like things that live
in far and exotic places, they are common and close by. As this text is very
complex, I would give a simpler task. I would have my students build two one
sentence summaries, one on why coyotes are keystone species and one on how the
students can help coyotes in their own area.
Lewis, Patrice. "If the Grid Fails, Will You Die?" World
Net Daily. N.p., 23 May 2014. Web, accessed 25 July 2017 at
<http://www.wnd.com/2014/05/if-the-grid-fails-will-you-die/>.
This article talks about what would happen to our society if the power grid
shut down. Electricity is a keystone to our society, and without it there would
be dramatic changes in the way we live, just like there are changes in the
ecosystem when a keystone specie is lost.
Magle, Seth B., and Lisa M.
Angeloni. "Effects of urbanization on the behaviour of a keystone
species." Behaviour 148.1 (2011): 31-54.
This text is an example of the effects
urbanization has on keystone species. It focuses on the black tailed prairie
dog in Denver, Colorado. The article suggests that when colonies of prairie
dogs become isolated due to urbanization, they first become more alert to their
surroundings, but after time they adjust and become even less alert than when
they were not isolated. Urbanization is having an effect on keystone species,
and knowing the behavioral changes will allow for better conservation and
management.
