Crop Failures and Food Riots

In the spring of 2008, many news outlets reported that rice crop failures in East Asia could have been avoided. An infestation of the brown plant hopper is the cause for the crop failure. The science knowledge and biotechnology needed to breed resistant rice plants have been in existence for several years. However, funds were not available to mass produce these rice strains and get them into the hands of rice growers. This is one example of crop failure that, when combined with other agricultural woes, fueled food riots around the world, but especially among the poorest people in the least developed nations.

The New York Times published an article that comprehensively describes how this preventable tragedy happened – World’s Poor Pay Price as Crop Research Is Cut. As with most sociopolitical issues, a combination of circumstances over a long period of time must be considered if one is to accurately account for the current crisis. The article conveys the history of agriculture research, including the Green Revolution of the 1960s and the great advances that emerged then. Ironically that successful movement contributed to the current lack of available funding; as agriculture problems were solved and world food supplies outpaced demand, research money was directed elsewhere.

The article, part of a series on the world’s food production, includes a nice depth and breadth of information concerning agricultural research. Several photos and related links are included.

How to Turn This News Event into an Inquiry-Based, Standards-Related Science Lesson

The issues described in the news article connect to the History and Nature of Science, Life Science, Science and Technology, and Science in Personal and Social Perspectives content standards of the National Science Education Standards. Here, we narrow our focus to the first two standards. However, this topic – world food supplies as related to agriculture and biotechnology – could easily serve as basis for an interdisciplinary unit in the middle grades.

Do any of the students have experience in growing vegetables? Ask students, what are some of the problems gardeners have to deal with in order to maintain their vegetables? What are some ways to deal with those problems? Help students to include the problem of insect pests in the discussion. Is it reasonable to assume that growers of crops on a large scale also have the same or similar problems? Can growers use the same approaches to deal with their problems that the gardener uses? Why or why not?

Ask students if they can identify one food plant, or crop, that is probably the world’s most common source of food. Consider keeping a list of all ideas and then asking the class to think carefully and critically when they answer these questions: What crop could probably be eliminated from the list, compared to the rest of the list? Why do they believe the food they are choosing to eliminate is probably not the world’s top food crop? You will hope that rice remains on the list!

Ask students to imagine that an insect has infested a large part of the world’s most important food crop. Consider putting the students in small groups in which they predict the consequences of an infestation. You might stipulate that they must have a clear prediction with logical justification for each domain: economy, culture, public health, government, military, and education. Next, ask them to articulate one or two questions that science could investigate in the hope of avoiding the consequences their group identified. For example, Which varieties of rice are most insect resistant? What other food crops can be grown in the areas where rice is currently grown? What nutritional substitutes should/could be distributed to areas where rice is in short supply? Students’ questions will vary widely and all are correct, as long as the questions can be subjected to scientific investigation and seem to point toward a solution to the stated problem.

Share with students the New York Times article, showing that such an event – insect infestation of an important crop – actually happened. Show them the pictures at the story’s web site. Inform them that the knowledge and technology necessary to prevent this disaster already exist. Ask students to speculate then on how this could have happened if people already know how to combat it. Lead them to understand the complexity of the history, funding, cultural values, and competition for funding as contributors to the situation. Finally, confirm and affirm the students’ predictions. They may have heard about food riots for example, in Africa and elsewhere. Ask them what direction they think governments and researchers should go next? Why?

As an extension, you could elaborate on the evolution aspect of the story: the way the bug has evolved through natural selection made possible by use of insecticides.

Here are additional resources from the National Science Digital Library Middle School Portal related to gardening, agriculture and natural selection: Thinking Green? Grow Your Own!; What Are Seed Banks and How Do They Work? and Dr. Saul’s Biology in Motion.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at

This post was originally written by Mary LeFever and published May 21, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/19/12 by Jessica Fries-Gaither.

After 50 Years, Scientists Still Not Sure How DEET Works

DEET (short for N,N-diethyl-meta-toluamide) is the most widely used insect repellent in the world for a very good reason – it works really, really well! Just a quick spray on exposed skin keeps mosquitoes, flies, fleas, chiggers, and ticks away. Developed by scientists at the U.S. Department of Agriculture and patented by the U.S. Army in 1946, millions of people worldwide use DEET to ward off vector-borne diseases. First of all, why would researchers study DEET if it works so well? While DEET is an effective repellent, it doesn’t work against all bugs, it’s corrosive to plastics and there are concerns about its effect on human health.


Structural Formula for N, N-diethyl-meta-toluamide (DEET).
Courtesy of Wikipedia – Click on the image for a larger version.

How DEET actually works has puzzled scientists for more than 50 years. Scientists long surmised that DEET masks the smell of the host, or jams or corrupts the insect’s senses, interfering with its ability to locate a host. Mosquitoes and other blood-feeding insects find their hosts by body heat, skin odors, carbon dioxide (breath), or visual stimuli.

Amazingly, within a few months this year, scientists from two different labs have come up with competing explanations of how DEET works. In March of 2008, researchers at Rockefeller University in New York, said that DEET jams odorant receptors in insect nervous systems, in effect masking odors that would ordinarily attract the bugs. According to Dr. Leslie B. Vosshall, a researcher who worked on the project, now that they know that DEET targets OR83b co-receptors, they can quickly screen thousands of other compounds in hope of finding one that is even more effective and has fewer disadvantages.

Are you sure, ask researchers at the University of California, Davis? Mosquitoes flee because of their intense dislike for the smell of the chemical repellent and not because DEET jams their sense of smell. In August 2008, in a paper published in The Proceedings of the National Academy of Sciences, they provide a simpler explanation. Mosquitoes, they say, smell DEET directly and avoid it.

Dr. Vosshall, involved in the earlier study, said that her team stood by its work, and that its findings were based on a variety of experiments. So for now, the jury is still out.

Connecting to the National Science Education Standards

These competing explanations on how DEET works provides a perfect example of one aspect of the nature of science – Scientific Claims are Subject to Peer Review and Replication. Researchers in labs across the world work on answering many of the same questions. The results of their work are published in peer reviewed journals so that researchers around the world can examine their data and logic, identify alternative explanations, and replicate observations and experiments. Peer review is an integral part of genuine scientific enterprise and goes on continuously in all areas of science.

The National Science Education Standards in the History and Nature of Science Content Standard G describes what middle school students should understand about this part of the nature of science, including:

It is normal for scientists to differ with one another about the interpretation of the evidence or theory being considered.

Different scientists might publish conflicting experimental results or might draw different conclusions from the same data.

It is part of scientific inquiry to evaluate the results of scientific investigations, experiments, observations, theoretical models, and the explanations proposed by other scientists.

Although scientists may disagree about explanations of phenomena, about interpretations of data, or about the value of rival theories, they do agree that questioning, response to criticism, and open communication are integral to the process of science.

Additional Resources

Read the entire National Science Education Standards online for free or register to download the free PDF. The content standards are found in Chapter 6.

Science For All Americans Online: The Nature of Science
Science for All Americans consists of a set of recommendations on what understandings and ways of thinking are essential for all citizens in a world shaped by science and technology.

Household Product Database
List of products that contain DEET.

Chemical Technical Summary for Public Health and Public Safety Professionals
The Department of Health and Human Services provides a summary of all medical cases and research done on DEET.

We Want Your Feedback

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. Let us know what you think and tell us how we can serve you better. We appreciate your feedback on all of our Middle School Portal 2 publications. You can also email us at

This post was originally written by Kimberly Lightle and published August 26, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 4/19/12 by Jessica Fries-Gaither.

Meet Juanita Constible: An Antarctic Scientist

Juanita Constible spent her holidays in an unusual way – traveling to the coldest, windiest, driest, and highest place on Earth! She’s on a scientific expedition with four other scientists from Miami University (OH) and Ohio State University, studying an unusual insect’s ability to survive cold temperatures.

Juanita Constible

We were lucky enough to interview Juanita about her trip!

BPPB: Tell us a bit about yourself.

JC: I am a technical analyst—sort of like a scientific advisor—with National Wildlife Federation’s coastal Louisiana program. I was trained as a wildlife ecologist and have studied a variety of animals across Canada and the U.S. I’ve been interested in science education since I was a graduate student, and enjoy sharing my love of nature and science with people of all ages.

BPPB: What is the purpose of your trip to Antarctica?

JC: I’m going to Antarctica with four other scientists to study the southernmost free-living insect in the world. This insect is called Belgica antarctica, but we call it Belgica for short because it doesn’t have a common name. In addition to helping the scientists, I will be sharing our experiences with K-12 students and teachers.

Belgica larvae on mud.

BPPB: How did you become interested in Belgica?

JC: I used to be the lab manager for the Laboratory of Ecophysiological Cryobiology at Miami University. The scientists in this lab study how animals like frogs, turtles, and flies survive extreme cold. Belgica was the most interesting study animal to me because it lives in Antarctica. Before I worked at Miami University, I had no idea there were insects, mites, ticks, or any other invertebrates in Antarctica.

Why is Belgica special? Why is your team studying it?

JC: Belgica is a tough little fly! It can survive freezing, the loss of over 70% of its body water, wide swings in pH, immersion in salt water, and long stretches with little to no oxygen. Over the next three years, the team will do field and laboratory studies to answer these questions:

Does Belgica typically survive the winter by freezing or dehydrating?

What role do proteins (specifically aquaporins and dehydrins) play in the winter survival of Belgica?

How does Belgica “know” when it’s time to get ready for winter?

BPPB: How did you get the chance to travel to Antarctica?

JC: Mostly luck, I think! Seriously, though, having science and education experience and a heck of a lot of enthusiasm helped.

BPPB: Tell us about the preparation for your trip.

JC: The most complicated part was the physical qualification process. Everyone spending part of a field season at a U.S. base in Antarctica has to meet minimum health requirements—which means lots of tests, lots of dental work, and lots of paperwork. The health requirements are for everyone’s safety, as it can be difficult, dangerous, and very expensive to get someone out of Antarctica quickly in the case of a medical emergency.

BPPB: Can we learn more about your trip? How can we follow along with your adventures?

JC: Absolutely! We have a blog (, a Facebook fan page (Miami University’s Antarctic Connection), and a website ( And I love answering questions. The best way to get in touch is through the comment section on our blog. That way, everybody gets to see the answers.

BPPB: How can teachers use this information in their classrooms?

JC: We’re going to touch on life science, physical science, history, math, and a bunch of other subjects, so there are connections to your entire curriculum. Consider using the materials as:

A daily reading warm up.

A hook for a science lesson on biological form and function, food webs, weather and climate, phase shifts of water, or another theme. Check out some of our polar lesson plans here:

Inspiration for a creative writing or journaling activity. For example, you could ask students to spend a few days writing blog entries about their home town from the perspective of a tourist.

A source of videos, sound clips, or photos for art projects or public speaking assignments.

A tool to encourage students to interact responsibly and safely with adults and their peers online.

Thanks to Juanita for answering our questions! Do you know of someone we should interview on the blog? Post a comment – we’d love to hear from you!

Forensic Science: A Hit in Middle School, Maggots and All

The latest online publication from the Middle School Portal is now available – Forensic Science: Middle School. We’ve searched the web for the best resources associated with this topic but I’m sure we haven’t found all the great ones. We’d like your help – do you know of other resources we should include? If you include Forensic Science topics in your curriculum we’d sure like to hear how you do it – please join in the conversation at the Middle School Portal 2 social network –!

Have You Seen an Arthropod Lately?

In their study of the life sciences, middle school students are making the transition from thinking strictly about individual organisms to developing an understanding of patterns of life found in ecosystems. The National Science Education Standards call for middle school students to analyze the internal structures, chemical processes, and common ancestry of all species, including the arthropods. This collection of web sites helps students to understand how arthropods as a group are alike, yet different, and how they manage to live together in their tiny world.

Arthropods in Their Microhabitats
Have your students get ready for a look at the world from an ant’s-eye-view! Students learn techniques for observing, identifying, and classifying arthropods within a microhabitat. Included in the seven lessons are instructions on how to build a Berlese funnel, how to trap ants for study, and how to make a simple net with fabric. Written for grades 6-10, these lessons are designed to showcase the diversity and variety of arthropods found living together in a given microhabitat.

The Wonderful World of InsectsNSDL Annotation
This site provides both general and in-depth coverage of a variety of arthropods. Students will be fascinated with the facts about insects: the largest and smallest, fastest and loudest, and most tolerant of cold or heat. Several pages are given over to discussing taxonomy, and a key to the orders of insects is included.

Amazing ArthropodsNSDL Annotation
Focusing on the Sonoran Desert, this activity is designed to help students identify arthropods found in Arizona: scorpions, ants, beetles, tarantulas, and millipedes. The activity includes background information and a student handout.

Ecology Explorers: Doing Science in Your SchoolyardNSDL Annotation
Students and teachers in the Phoenix, Arizona, area are given the opportunity to take part in real research led by scientists at this web site. Students learn to use data collection protocols, develop hypotheses, and carry out experiments as they study patterns in urban ecosystems.

We Need Your Help

We want and need your ideas, suggestions, and observations. What would you like to know more about? What questions have your students asked? We invite you to share with us and other readers by posting your comments. Please check back often for our newest posts or download the RSS feed for this blog. You can also request email notification when new content is posted (see right navigation bar).

Let us know what you think and tell us how we can serve you better. We want your feedback on all of the NSDL Middle School PortalNSDL Annotation publications. Email us at