This is a place – the importance of conducting local research

Below we have reproduced an article by Kathryn M. Flinn from Belt Magazine. The original post can be found here.

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Like many teenagers, I could not wait to leave the place where I grew up, in western Pennsylvania. There, my family often took a walk on a nearby Rails-to-Trails path that I liked to call the Trail of Ecological Destruction. This former railroad bed lined with invasive shrubs crosses creeks turned orange by acid mine drainage, passes the sewage treatment plant and the recycling center, and ends at a coal-fired power plant that releases more sulfur dioxide than any other power plant in the nation. I wanted to hike the Appalachian Trail, not this devastated landscape.

But, after years of working as an ecologist, I have come to realize that grim terrain like this holds endless ecological interest. I recently took a position as a biology professor near Cleveland, and I’m fully confident that ecological research in the immediate region can sustain a career’s worth of curiosity. But I choose to do local ecology for another compelling reason — I have found that the local, lived-in landscape actually works best as a tool for helping people discover and value the environment. I do local ecology not because it’s cheap, not because it’s convenient, but because it has unique educational value.

Any college worth its salt has a Study Abroad office. Just once, I would like to direct a student to the Study Our Home office.

Yet studying ecology in the Rust Belt clearly has a public relations problem. Students, parents, administrators, and funders often fail to understand the appeal of local ecology. Even some ecologists, with their focus on biological diversity, tend to ignore the local in favor of places seen as globally significant or simply exotic. In fact, it is surprisingly easy to earn a biology degree without once interacting with organisms in a local habitat.

Any college worth its salt has a Study Abroad office. Just once, I would like to direct a student to the Study Our Home office. After all, the word “ecology” means the study of home. We have biology courses where students spend half a semester studying the natural history of Ecuador and half a semester photographing blue-footed boobies. What might happen if students spent an equal amount of time immersing themselves in their own landscapes?

To begin to focus attention on the local landscape, I realized that I need to be able to recognize, articulate, and communicate the specific lessons of local ecology. What can students learn locally better than anywhere else? What exactly am I teaching when I teach ecology in urban wastelands, wetland restorations, the humblest of parks, or wherever is nearest to hand?

By teaching ecology in a CVS parking lot, I send the same message: This is a place worth noticing, a place of ecological interest.

One late spring, I had planned a pollination ecology lab, but no native plants were flowering yet. So I took my students to a CVS parking lot, where a hedge of ornamental quince bushes had a pink riot of flowers mobbed by bees. After some urging, they set to work with their field notebooks, hand lenses, and butterfly nets. What is the difference if I teach pollination ecology in a rainforest in Costa Rica or in a CVS parking lot? Students learn the same observation skills and pollination ecology techniques. The same ecological principles pertain. The difference is that, to get to the rainforest, students have endured a six-hour flight and likely a harrowing bus ride. They have paid thousands of dollars and donned their technical polyester zip-off pants. All of this has communicated to them that what they are about to see is worth paying attention to. By teaching ecology in a CVS parking lot, I send the same message: This is a place worth noticing, a place of ecological interest.

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The first lesson local ecology teaches is: Pay attention. Once I had a 100-year-old holly tree in my urban front yard, but not until I did an assignment I had given my students did I learn about holly leaf miners. Apparently there are several species of insects whose whole life consists of making traces in holly leaves, and there are several scientists who have spent their careers figuring out this interaction. I went outside. Sure enough, my holly tree had them. Sharing the street with holly leaf miners made it look slightly different.

Last fall my students discovered a spectacularly armored wheel bug in an abandoned orchard behind a baseball field. They had no idea that something like a wheel bug could exist. Do they respect this place more, given the possibility of wheel bugs?

“Most of us are still related to our native fields as the navigator to undiscovered islands in the sea,” Thoreau wrote late in life. “We can any afternoon discover a new fruit there, which will surprise us by its beauty or sweetness. So long as I saw in my walks one or two kinds of berries whose names I did not know, the proportion of the unknown seemed indefinitely, if not infinitely, great.” In fact, no one has the least idea what is going on under our noses. Geneticist Christopher Mason and his colleagues recently reported that almost half of the DNA they found in the New York City subway system was from organisms unknown to science. The New York Times quoted Mason as saying, “People don’t look at a subway pole and think, ‘It’s teeming with life.’ After this study, they may. But I want them to think of it the same way you’d look at a rain forest, and be almost in awe and wonder, effectively, that there are all these species present.”

Is it any wonder children don’t spend enough time experiencing nature in their backyards when parents hardly credit their backyards with offering an authentic experience of the natural world?

The second lesson: There is plenty left to discover, and you can start right here. Also, what you discover might change your mind.

Deep and inchoate ideas about how people interact with nature have a surprisingly strong influence on the teaching and learning of ecology. In his book Thoreau’s Country, David Foster pointed out that when Thoreau built his cabin, the landscape around Walden Pond was extensively farmed, fenced and populated. Diana Saverin recently noted in the Atlanticthat while Annie Dillard wrote Pilgrim at Tinker Creek, she was a suburban housewife. Few people remember that Edward Abbey spent his formative years in western Pennsylvania, near the town of Home. These facts need to be emphasized because many implicitly assume that only an individual alone in the wilderness can experience nature. Is it any wonder children don’t spend enough time experiencing nature in their backyards when parents hardly credit their backyards with offering an authentic experience of the natural world?

I might walk to work on the streets of Berea, Ohio, and daydream about building a cabin in Alaska or backpacking on the Pacific Crest Trail. Of course, there’s nothing wrong with valuing wilderness or visiting Alaska. But this thinking can demean my surroundings. There are probably plants in the sidewalk cracks I can’t identify yet.

If everywhere is nature, why not turn the question around? What is the difference if I teach pollination ecology in the Costa Rican rainforest instead of the CVS parking lot? The difference, I think, is that we live here. Students buy ramen noodles at this CVS. They are complicit in the processes that led to the paving, the planting of ornamental quince bushes, and the importing of European honeybees. Whatever happens here, to the asphalt and the quinces and the bees, they need to know about it, because they have to live with it. As Thoreau exhorts in Wild Fruits, his belatedly discovered final manuscript:

Do not think, then, that the fruits of New England are mean and insignificant while those of some foreign land are noble and memorable. Our own, whatever they may be, are far more important to us than any others can be. They educate us and fit us to live here in New England. Better for us is the wild strawberry than the pine-apple, the wild apple than the orange, the chestnut and pignut than the cocoa-nut and almond, and not on account of their flavor merely, but the part they play in our education.

The landscapes where we live are the ones we are most responsible for, and they teach us about the consequences of our actions.

Thoreau does not call wild strawberries “just as interesting” as pineapples. He does not say we could learn “just as much” from our local fruits. He calls them “far more important to us” — specifically for their educational value. Local fruits and local places teach us about our roles in nature — not just as naturalists or scientists, but as parts of ecosystems. The landscapes where we live are the ones we are most responsible for, and they teach us about the consequences of our actions.

My own sense of responsibility for the landscape where I grew up burgeoned when I learned how my ancestors had participated in shaping it. In the 1790s, my great-great-great-great grandfather John McCullough bought 250 acres of forested land near Burnside, Pennsylvania, and spent the rest of his life clearing and farming it with his wife and twelve children. In 1880, his granddaughter Mollie married a logger, who also built things out of wood, especially wagons. Mollie’s brother owned a sawmill, ran a lumber company, and opened a coal mine. Through the first decades of the 1900s, her daughter and son-in-law worked for a coal company. By the 1970s, my father was growing 20 million trees a year on farmland John McCullough and his neighbors had cleared. I grew up with young forests and orange creeks because my own family had created them. By teaching local ecology, I give students a similar sense: This is the place where we live, that we have shaped and continue to shape. This is the place where our children will live.

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Ecologist Josh Donlan and other advocates of rewilding — especially reintroducing large carnivores — start from the premise that “earth is now nowhere pristine.” They argue that because our actions affect every ecosystem on earth, we should claim this responsibility, and manage ecosystems intentionally. Surely there are no better case studies in how human actions shape landscapes than the landscapes where we live. Certainly, educators need to help students make global connections — when they drive across campus instead of walking, they might contribute infinitesimally to a change in the mist regime of an epiphytic orchid in a rainforest canopy in Costa Rica. Interactions with our local landscapes are simply more immediate and concrete. When I take students in western Pennsylvania to compare invertebrate communities in streams with and without acid mine drainage, they understand the results within the context of their lives. They come from old company towns. Their uncles sell mining equipment. Their neighbors work for the power plant. They mountain bike on slag piles. And they like to fish. Doing local ecology provides a direct impetus to take ownership of our home landscapes, to accept our responsibility as stewards.

This third lesson is perhaps the greatest social benefit of local ecology. It is well to cultivate adults who can pay attention and continue to learn from nature. “Those who dwell, as scientists or laymen, among the beauties and mysteries of the earth, are never alone or weary of life,” wrote Rachel Carson, who developed her sense of wonder in an industrial city near Pittsburgh. But as a society we also need citizens who take responsibility for the ways they interact with nature. This may be best learned through the intimate and practical interactions we can only have with the landscapes in which we live.

Kathryn M. Flinn is an ecologist originally from Indiana, Pennsylvania.  In August, she will move to Baldwin Wallace University in Berea, Ohio. Her website, https://kathrynflinn.wordpress.com/, has more information about her teaching and research.

Springing forward

Scientist Shaun collecting phenology data in the climate change experiment. He is recording the date that the first flowers emerge for dame’s rocket.

Sean Mooney, a high school researcher, collecting phenology data in the climate change experiment. He is recording the date that the first flowers emerge for dame’s rocket.

The Reading Level 1 activities are as follows:

The Reading Level 3 activities are as follows:

Éste Data Nugget también está disponible en Español:

Every day we add more greenhouse gases to our air when we burn fossil fuels like oil, coal, and natural gas. Greenhouse gasses trap the sun’s heat, so as we add more the Earth is heating up! What does climate change mean for the species on our planet? The timing of life cycle events for plants and animals, like flowering and migration, is largely determined by cues organisms take from the environment. The timing of these events is called phenology. Scientists studying phenology are interested in how climate change will influence different species. For example, with warming temperatures and more unpredictable transitions between seasons, what can we expect to happen to the migration timings of birds, mating seasons for animals, or flowering times of plants?

Scientists collecting phenology data in the climate change experiment. They are recording the date that the first flowers emerge for dame’s rocket.

Scientists collecting phenology data in the climate change experiment.

Plants are the foundation for almost all life on Earth. Through photosynthesis, plants produce the oxygen (O2) that we breathe, food for their own growth and development, food for animals and microbes, and crops that provide food and materials for human society. Because plants are so important to life, we need to find out how climate change could affect them. One good place to start is by looking at flowering plants, guided by the question, how will increased temperatures affect the phenology of flowering? One possible answer to this question is that the date that flowers first emerge for a species is driven by temperature. If this relationship is real, we would expect flowers to emerge earlier each year as temperatures increase due to climate change. But if flowers come out earlier and earlier each year, this could greatly impact plant reproduction and could cause problems for pollinators who count on plants flowering at the same time the pollinators need the pollen for food.

Shaun, Mark, Elizabeth, and Jen are scientists in Michigan who wanted to know if higher temperatures would lead to earlier flowering dates for plants. They chose to look at flowers of dame’s rocket, a leafy plant that is related to the plants we use to make mustard! Mark planted dame’s rocket in eight plots of land. Plots were randomly assigned to one of two treatments. Half of the plots were left to experience normal temperatures (normal), while the other four received a heating treatment to simulate climate change (heated). Air temperatures in heated plots increased by 3°C, which mimics climate change projections for what Michigan will experience by the end of the century. Mark, Elizabeth, and Jen measured the date that each plant produced its first flower, and the survival of each plant. The scientists predicted that dame’s rocket growing in the heated plots would flower earlier than those in the normal plots.

 Featured scientists: Shaun Davis from Thornapple Kellogg Middle School and Mark Hammond, Elizabeth Schultheis, and Jen Lau from Michigan State University

Flesch–Kincaid Reading Grade Level = The Reading Level 3 activity has a score of 9.2; the Level 1 has a 6.4.

Flowers of Hesperis matronalis (dame’s rocket), a species of mustard that was introduced to the U.S. from Eurasia.

Flowers of Hesperis matronalis (dame’s rocket), a species of mustard that was introduced to the U.S. from Eurasia.

Additional teacher resources related to this Data Nugget include:

  • If you would like your students to interact with the raw data, we have attached the original data here. The file also includes weather data over the course of the experiment if students want to ask and explore independent questions.

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Data Nuggets’ First Publication Out in the American Biology Teacher

We just had our first Data Nugget publication accepted to the American Biology Teacher in their January 2015 issue. We hope this paper will introduce Data Nuggets to a broader audience of teachers. Click here for a PDF!

Schultheis, E. H., and M. K. Kjelvik. 2015. Data Nuggets: Bringing Real Data into the Classroom to Unearth Students’ Quantitative & Inquiry Skills. The American Biology Teacher 77(1):19-29.

NIMBioS Working Group: Expanding Data Nuggets by Developing and Assessing this Integrative Resource to Increase Quantitative Literacy

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On January 7-9th at NIMBioS headquarters in Knoxville, TN, the Data Nuggets working group brought together a diverse team of leaders in curriculum reform (K-12 and undergraduate), education resource assessment, education researchers, mathematicians, biologists, and a high school teacher. This working group served as a mechanism to bring NIMBioS resources and leaders in science education research and reform together in an effort to develop a national resource focused on integrating mathematics and science, particularly in the fields of ecology and evolutionary biology. The group has three objectives:

  • Identify skills necessary for progression towards quantitative literacy and discuss the role of Data Nuggets in acquiring these skills
  • Assess the efficacy of Data Nuggets as an educational tool
  • Build a library of resources for use alongside Data Nuggets in undergraduate classrooms

The group discussed common difficulties experienced by students when performing tasks that merge science content with quantitative skills, and how Data Nuggets can alleviate these difficulties. Based on these discussions, our next steps are to identify specific quantitative skills we want students to develop by using Data Nuggets. These learning outcomes will inform the development of a preliminary assessment tool that we will use to examine student gains after using Data Nuggets. Additionally, we hope to extend Data Nuggets to the undergraduate classroom and will be piloting Data Nuggets in introductory biology and math courses. We will organize professional development sessions for faculty to learn about and create Data Nuggets.

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Meeting 1 participants (L to R): Louise Mead, Melissa Kjelvik, Molly Stuhlsatz, Laurel Hartley, Julie Morris, Paul Strode, Kristin Jenkins, Elizabeth Schultheis, Jeremy Wojdak, Ariel Cintron-Arias, Robert Mayes, Gordon Uno.

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Blog Post on the Molecular Ecologist

Data Nuggets were featured on the Molecular Ecologist blog. Article is reproduced below, and can be found on their blog here.

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Increase your broader impacts with Data Nuggets

This week we have a special guest post by Elizabeth Schultheis, a PhD candidate at Michigan State University and the Kellogg Biological Station, to describe her Data Nuggets project. Data Nuggets is a great way to invest in the scientific community of the future by making research accessible to K-12 educators and students in new and exciting ways.

Broader impacts can be hard. 

We’ve all had that moment while writing an NSF grant proposal where we have to discuss the broader impacts of our research and demonstrate that our work contributes to society. The NSF makes it clear that they highly value projects with significant broader impacts; grants that do not explicitly address them will be returned without review, and some reviewers give them equal weight to the intellectual merit of a project when making funding decisions. Additionally, it is no longer enough to train undergraduates when performing our research, or TA a course where we discuss our research. The NSF is looking for creative answers to their call for projects that both improve our understanding of science and benefit society.

 But they don’t have to be.

Data Nuggets were designed to help scientists improve their communication skills and share the story of their research with a broad audience. When creating a Data Nugget you increase your broader impacts by:

  • Improving STEM education at all levels, including K-12 and undergraduate classrooms
  • Increasing your public outreach by disseminating your research findings to a broad audience and putting your data into a format that nonscientists can understand
  • Making science relatable by sharing your journey of exploration and discovery with students, increasing the passion for science and retention in STEM fields
  • Providing a snippet of data from your research, allowing students to analyze and interpret messy, real data as opposed to the polished data in textbooks that is not a realistic outcome of experimentation
  • Showing students that scientists are not all old men in lab coats, but can be done in a variety of settings by anyone with a passion for the natural world

What are Data Nuggets?

Data Nuggets are worksheets that bring data collected by scientists into the classroom, giving students the chance to work with real data – and all its complexities. By working with real data, students practice interpreting quantitative information and making claims based on evidence. The standard format of each Nugget provides a brief background to a researcher and their study system along with a small, manageable dataset. Students are challenged to answer a scientific question, use the dataset to support their claim, and construct graphs to facilitate data interpretation. Because of their simplicity and flexibility, Data Nuggets can be used throughout the school year as students build confidence in their science and quantitative skills.

Making your own Data Nugget

So what do you need to do to make a Data Nugget from your own research? Basically, you need to tell a story about your research and the process that lead you to your ideas and questions. This story should be written in a very accessible format, leaving out jargon or unnecessary complicated subjects. With this story you share a small dataset from your work, and a short description of your interpretation of these findings to help teachers discuss this topic with students in class.

We have detailed instructions available on our website to guide you through the steps of making a Data Nugget. Use our template to guide you through each simple step. We also have presentation slides and some cool resources in case you’re feeling stuck and need some inspiration. We are so excited to help you create a Data Nugget of your own; please contact Liz (eschultheis@gmail.com) or Melissa (kjelvikm@gmail.com) if you have any questions!

Future of Data Nuggets

Our next step for Data Nuggets is to formally assess improvements in student learning and attitudes about science when using these worksheets as part of their curriculum. We hope that soon scientists who create Data Nuggets will not only be able to say they have created a resource that is used in classrooms across the country, but that they are part of a project that improves students’ scientific understanding and comfort using quantitative data to answer questions.

For updates on Data Nuggets, like us on Facebook and follow us on Twitter! Our first journal publication is coming out in the American Biology Teacher in their January 2015 issue.

Shooting the poop

The activities are as follows:butterfly

Imagine walking through a forest in the middle of summer. You can hear birds chirping, a slight breeze rustling the leaves, and a faint pinging noise like rain. However, what you hear is not rain – it is the sound of millions of forest insects pooping!

If we look closer to see who is making all this frass (insect poop) you’ll notice there are tons of caterpillars amongst the leaves. You might see caterpillars eating plants and hiding from predators. Some caterpillars might camouflage themselves, while others build shelters from leaves to avoid being seen. Others are brightly colored to warn predators that they have chemicals that make them taste awful.

The silver-spotted skipper is a caterpillar that lives in the forest. They have a variety of defense strategies against enemies, including building leaf shelters for protection. For these insects, the sight and smell of poop might alert predators that there is a tasty meal nearby. Usually caterpillars keep moving and leave their frass behind, but this species builds shelters and isn’t able to keep moving because they need their shelters for protection.

Martha is a behavioral biologist who studies these insects. While raising silver-spotted skipper caterpillars in the lab, Martha noticed that they were making a pinging noise in their containers. Upon further observation, she discovered that they “shoot their poop”, sometimes launching their frass over 1.5m! Martha wanted to figure out why these caterpillars might have this very strange behavior. Perhaps launching their frass is a way to avoid being found by predators.

To evaluate whether the smell of frass helps predators find and locate silver-spotted skippers, Martha conducted an experiment with a wasp predator that eats these caterpillars. She allowed two silver-spotted skippers to build shelters on a leaf and then carefully removed the caterpillars. She then inserted 6 frass pellets into one of the shelters, and 6 beads designed to look like frass but with no smell (control treatment) into the other shelter. She placed the leaf with the two shelters in a cage containing an actively foraging wasp colony (n = 10 wasps). She recorded how many times the wasps visited each shelter (control beads or frass) and how much time the wasps spent exploring each shelter. She expected wasps would spend more time exploring the shelters with the frass than they would the control shelters.

Featured scientist: Martha Weiss from Georgetown University. Written by Kylee Grenis.

Flesch–Kincaid Reading Grade Level = 9.6

Additional teacher resources related to this Data Nugget include:

YouTube videos of the silver-spotted skipper (Epargyreus clarus) “shooting its poop” (aka. ballistic defecation). These videos would be great to show in class after students have read the Research Background section to help engage them with the system.

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Student guide for reading a scientific paper

Graduate student Kylee Grenis from the University of Denver has developed a guide for students to help them read the primary literature. A PDF of her guide How to read a scientific paper can be found on our Resources page!
 

How to Read a Scientific Paper

As your scientific career begins to blossom, you will need to incorporate an understanding of the scientific literature into your lab report. Academic sources are considered to be reputable because they go through an extensive peer-review process to determine whether there is scientific merit and proper methodology to support the claims of the study. Wikipedia does not have this extensive process, which is why it is not acceptable to cite this source in your lab reports.

A scientific paper is ranked in importance based on the number of times it is cited, meaning how many other papers reference it within their own text. Papers that are cited hundreds of times are considered to be foundational papers in the field. Papers that are cited only once or twice will tend to be very specific or were published recently. You may need to rely on both foundational papers and more recent works to write a lab report.

Understanding Articles

It can be really intimidating to read primary literature. Scientists like to use a lot of jargon that is specific to their field and bring up theories you may not be familiar with. But, once you slow down and take the time to really dig into the article, you can find a lot of useful information and inspiration as well as additional relevant papers to read. When you really concentrate on an article, it should take you at least an hour to read. Think of each journal article as a textbook chapter. Even though an article may be only 12 pages long, it will have a lot of information to sort through.

When I read a journal article, I keep a notebook close by to write down my thoughts, define terms, and record key findings. This way I have a record of papers I’ve read and I can quickly go back and find out what that paper was about. Here is my methodology for reading a journal article.

Going Through a Scientific Paper

Abstract

Articles include an abstract for a reason. Abstracts give a quick overview of the paper’s topic, methods, and findings. However, it is not a great idea to solely read abstracts in place of the entire paper. You’ll find more information, and gain a better understanding of how scientists think and convey their findings, by reading the entire paper. Besides, if you never practice reading articles, it will never get easier.

  • Question 1: While reading the abstract, see if you can determine what the author’s hypothesis/hypotheses are.
  • Question 2: Identify the general findings. These are important to keep in mind as you delve into the paper.

Introduction

The introduction of the paper should have an overview of the general principles, hypotheses, or theories, tested in the study. It should also explain why they are using the particular organism or system of study. Lastly, it should include the hypotheses tested.

In addition to introducing key concepts to frame the rest of the paper, the introduction will have lots of terminology used throughout the article. If there are any terms you do not understand, look them up now as you will probably see them again. It will save you lots of strife and increase your vocabulary.

The introduction is also a great place to find additional sources. Because introductions introduce key theories and study systems, they can be great resources for finding both more general and more specific information.

  • Question 3: While reading the introduction, identify general theory explanations, study systems, hypotheses and/or predictions.
  • Question 4: Define any terms you do not already know.
  • Question 5: Highlight two additional sources you would look up for more information.

Methods

The methods section should cover locations, dates, details of experimental design, and statistical analyses used. Scientific studies generally fall into two camps: observational or manipulative studies. Observational studies do not manipulate any variables; they rely on existing natural variation to find relationships between variables. Experimental studies use controlled manipulations to determine relationships between the independent and dependent variables. The methods section will also outline statistical analyses used to determine these relationships. Do not be scared by the statistics! Just realize that these are tests the author uses to find whether the relationship between the independent and dependent variable is statistically real or if it is a function of random chance.

  • Question 6: Highlight where and when the experiment was conducted.
  • Question 7: Determine the type of study. Is it observational or manipulative? Does this determine the experimental design used?

Results

The results section is what you have been waiting for! This section shows the results of the study through the statistical analyses. Note that there are no interpretations of the data. The results section should simply report the data. The author will describe the results of the statistical analyses by reporting the test statistic (a number calculated from the data to determine the p-value; it varies between statistical tests), the number of independent data points (degrees of freedom or df), and the p-value (significance value). P-values of less than 0.05 are considered to be significant.

Additionally, take a look at the figures. The figures will be a graphical representation of the data. You may already be familiar with a few types of common graphs. A scatter plot will show the relationship between a continuous independent variable and a continuous dependent variable; continuous variables have variable limits, like the temperature outside. Scatter plots with a best-fit line are common with regression statistical analyses.

Another graph you are probably familiar with is the bar graph. Bar graphs show the relationship between a categorical independent variable and a continuous dependent variable; categorical variables are those where data points are grouped. For example, different treatment groups, like fertilized or non-fertilized, would be categorical while plant measurements, like number of leaves or plant height, would be continuous. Statistical tests that commonly use bar graphs to report data are the t-test and ANalyses Of VAriance (ANOVA).

  • Question 8: Determine the statistical tests reported in the results. Does this match with those from the methods section?
  • Question 9: Look at the figures. Determine the independent and dependent variables. Are they continuous or categorical? How can you tell?
  • Question 10: Find each figure citation (e.g. Fig. 1) in the text of the results section. Does the text match what the figure shows?

Discussion

The discussion section will interpret the results of the data and place them in the greater context of the research done in this field. You can think of the discussion section as a joining of the introduction section and the results section. The discussion should mention whether the results support or do not support the hypotheses. If the data does support the hypotheses, the authors should delve into why this is important, how it relates to other studies, and the implications of the findings. Note that the authors will refer back to figures and tables from the results section to support their claims. If the data does not support the hypotheses, the authors will delve into why this is important, how it relates to other studies, and the implications of the findings. Even if the data do not support the original hypotheses, it is still important and interesting!

  • Question 11: Determine whether the hypothesis was supported or refuted.
  • Question 12: Look at the references back to the results section. Do the figures support the claims and interpretations of the authors?
  • Question 13: Think all the way back to the abstract. After reading the entire article, does the abstract give an accurate picture of the entire study?

Think About It

Once you have a pretty clear idea about the main points of the article, look at other papers that cite the article. You can scan the new article to find the original article citation and double-check your interpretation.

  • Think About It Tip 1: Did the citing authors reach the same conclusions you did? If not, what did they find most important?
  • Think About It Tip 2: Do you agree with their interpretation?
  • Think About It Tip 3: Think about your own study. How will this article help you support your hypotheses or your results?

Sexy smells

Danielle holding a male junco. Notice the white tail feathers.

Danielle holding a male junco. Notice the white tail feathers.

The activities are as follows:

Animals collect information about each other and the rest of the world using multiple senses, including sight, sound, and smell. They use this information to decide what to eat, where to live, and who to pick as a mate. Choosing a mate is an important decision that requires a lot of information, such as how healthy a potential partner is, and information about their genes. Mate quality can affect how many offspring an animal has and if their genes will get passed on to the next generation.

Danielle removing preen oil from a junco.

Danielle removing preen oil from a junco.

Many male birds have brightly colored feathers that are attractive to females. For example, the peacock has bright and elaborate tail feathers that are thought to communicate a male’s quality to the females. Besides using their sense of sight to see feathers, female birds may use their other senses to gather information about potential mates as well. Danielle is a biologist and she wanted to figure out if birds use vision and their other senses, such as smell, to determine the quality of potential mates.

Danielle decided to research how dark-eyed juncos communicate through their sense of sight and smell. Dark-eyed juncos are a type of sparrow. They are not colorful birds like peacocks, but they do have bright white feathers in their tails. Male dark-eyed juncos have more tail-white than females. Danielle thought is possible that females use the amount of white in a male’s tail to determine whether he is a high quality mate. Danielle was also interested in several chemical compounds found in junco preen oil, which birds spread on their feathers. This preen oil contains compounds that give birds their odor. Danielle found that males and females have different odors! Just as males have more white in their tail feathers, they also produce more of a chemical called 2-pentadecanone. Danielle wanted to test whether this chemical functioned as a signal to females of mate quality.

A preen gland where birds produce preen oil.

A preen gland where birds produce preen oil.

To test her two potential hypotheses, Danielle captured male juncos at Mountain Lake Biological Station in Virginia. She measured the amount of tail-white by estimating the proportion of each tail feather that was white, and adding up the values from each feather. She also took preen oil samples and measured the percent of each sample that was made up of 2-pentadecanone. She followed these birds for one breeding season to find out how many offspring they had. If females pick mates based on visual ornaments, then she predicted males with more tail-white would have more offspring. If females pick mates based on smell, then she predicted males with more 2-pentadecanone would have more offspring.

Featured scientist: Danielle Whittaker from Michigan State University

Flesch–Kincaid Reading Grade Level = 9.4

Additional classroom resources for this Data Nugget:

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Dangerous Aquatic Prey: Can Predators Adapt to Toxic Algae?

Figure 1: Scientist Finiguerra collecting copepods at the New Jersey experimental site.

Figure 1: Scientist Finiguerra collecting copepods at the New Jersey experimental site.

The activities are as follows:

Phytoplankton are microscopic algae that form the base of all aquatic food chains. While organisms can safely eat most phytoplankton, some produce toxins. When these toxic algae reach high population levels it is known as a toxic algal bloom. These blooms are occurring more and more often across the globe – a worrisome trend! Toxic algae poison animals that eat them, and in turn, humans that eat these animals. For example, clams and other shellfish filter out large quantities of the toxic algae, and the toxic cells accumulate in their tissues. If humans then eat these contaminated shellfish they can become very sick, and even die.

One reason the algae produce toxins is to reduce predation. However, if predators feed on toxic prey for many generations, the predator population may evolve resistance, by natural selection, to the toxic prey. In other words, the predators may adapt and would be able to eat lots of toxic prey without being poisoned. Copepods, small crustaceans and the most abundant animals in the world, are main consumers of toxic algae. Along the northeast coast of the US, there is a toxic phytoplankton species, Alexandrium fundyense, which produces very toxic blooms. Blooms of Alexandrium occur often in Maine, but are never found in New Jersey. Scientists wondered if populations of copepods that live Maine were better at coping with this toxic prey compared to copepods from New Jersey.

Figure 2: A photograph of a copepod (left) and the toxic alga Alexandrium sp. (right).

Figure 2: A photograph of a copepod (left) and the toxic alga Alexandrium sp. (right).

Scientists tested whether copepod populations that have a long history of exposure to toxic Alexandrium are adapted to this toxic prey. To do this, they raised copepods from Maine (long history of exposure to toxic Alexandrium) and New Jersey (no exposure to toxic Alexandrium) in the laboratory. They raised all the copepods under the same conditions. The copepods reproduced and several generations were born in the lab (a copepod generation is only about a month). This experimental design eliminated differences in environmental influences (temperature, salinity, etc.) from where the populations were originally from.

The scientists then measured how fast the copepods were able to produce eggs, also called their egg production rate. Egg production rate is an estimate of growth and indicates how well the copepods can perform in their environment. The copepods were given either a diet of toxic Alexandrium or another diet that was non-toxic. If the copepods from Maine produced more eggs while eating Alexandrium, this would be evidence that copepods have adapted to eating the toxic algae. The non-toxic diet was a control to make sure the copepods from Maine and New Jersey produced similar amounts of eggs while eating a good food source. For example, if the copepods from New Jersey always lay fewer eggs, regardless of good or bad food, then the control would show that. Without the control, it would be impossible to tell if a difference in egg production between copepod populations was due to the toxic food or something else.

Featured scientists: Michael Finiguerra and Hans Dam from University of Connecticut-Avery Point, and David Avery from the Maine Maritime Academy

Flesch–Kincaid Reading Grade Level = 10.6

There are three scientific papers associated with the data in this Data Nugget. The citations and PDFs of the papers are below. 

Colin, SP and HG Dam (2002) Latitudinal differentiation in the effects of the toxic dinoflagellate Alexandrium spp. on the feeding and reproduction of populations of the copepod Acartia hudsonicaHarmful Algae 1:113-125

Colin, SP and HG Dam (2004) Testing for resistance of pelagic marine copepods to a toxic dinoflagellate. Evolutionary Ecology 18:355-377

Colin, SP and HG Dam (2007) Comparison of the functional and numerical responses of resistant versus non-resistant populations of the copepod Acartia hudsonica fed the toxic dinoflagellate Alexandrium tamarense. Harmful Algae 6:875-882