Granite Helps Scientists Piece Together Rodinia

If you’ve taught plate tectonics at the middle school level, you’re probably quite familiar with the supercontinent Pangaea. But did you know that Pangaea was not the only supercontinent in earth’s history – just the last to date? Millions of years before Pangaea, another supercontinent known as Rodinia united all of earth’s landmass in an unusual configuration. While we tend to think of Pangaea as the “starting point,” earth’s land and ocean basins have been continually shaped throughout geologic time through a supercontinent cycle.

While Pangaea certainly gets more press, Rodinia was the star of an article in the July 11, 2008 edition of Science. As summarized in a National Science Foundation News release, John Goodge’s team was collecting geologic specimens in the Transantarctic Mountains when they discovered a single granite boulder atop Nimrod Glacier.

Andrew Barth (L) and Devon Brecke (R), collecting glacial moraine samples in the Miller Range of the Transantarctic Mountains. Photo courtesy of John Goodge, University of Minnesota.

Subsequent chemical and isotopic tests indicated that the boulder was strikingly similar to a belt of igneous rock running through the southwestern United States. These similar chemical and isotopic signatures provided support for the SWEAT (southwest United States East Antarctica) hypothesis, which states that East Antarctica was connected to the southwestern United States approximately one billion years ago, as part of the global supercontinent Rodinia.

The supercontinent Rodinia as it began to break up approximately 750 million years ago.

At the heart of Rodinia was Laurentia, or the precursor to most of North America. Debate exists, however, on whether East Antarctica, Australia, Siberia, or South China fit with the western margin of Laurentia. This geologic discovery provides three lines of evidence in support of an East Antarctica – Laurentia connection.

Researchers theorize that about 600-800 million years ago, a portion of Rodinia broke away, gradually drifting southward to become eastern Antarctica and Australia. This movement just predates the Cambrian explosion, a rapid diversification of life and sudden appearance of complex organisms. Goodge explains that “there are ideas developing about these connections between the geo-tectonic world on the one hand and biology on the other.” It is possible that the shifting and colliding of continents, erosion, and influx of minerals and chemicals into the ocean may have provided nutrients to support a growing diversity of organisms.

Connecting to the National Science Education Standards

As with a discussion of Pangaea or plate tectonics in general, this article provides an opportunity to meet the Earth and Space Science standard’s various concepts. According to the National Science Education Standards, “The idea of systems provides a framework in which students can investigate the four major interacting components of the earth system – geosphere, hydrosphere, atmosphere, and the biosphere. In this holistic approach to studying the planet, physical, chemical, and biological processes act within and among the four components on a wide range of time scales to change continuously earth’s crust, oceans, atmosphere, and living organisms.” The holistic approach described in the NSES is reflected in this study’s use of geologic evidence to explain an important biological phenomenon.

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

Rather than spark a new lesson, this current event provides an opportunity to revisit a familiar unit on plate tectonics, geologic time, and rocks and minerals. Most teachers include a discussion of Alfred Wegner and the evidence for his theory of plate tectonics, including similar fossilized plants and reptiles found in South America and Africa.

After students understand how Wegner used geologic and fossil evidence to reconstruct Pangaea, present the evidence from this most recent discovery. Ask them to explain how the same type of granite could be found in eastern Antarctica and the southwest United States. Once students conclude that the two continents must have been connected, re-examine a diagram of Pangaea, which shows an African-Antarctic connection, not a North America-Antarctic one. How, then, could these two places have similar rocks?

A reconstruction of the supercontinent Pangaea. Image courtesy of Kieff via Wikimedia.

Referring to geologic time may help at this point. Using a modified time scale, remind students that Pangaea existed approximately 200 million years ago, while earth is approximately 4.6 billion years old. What did earth’s surface look like before Pangaea? Lead students to the conclusion that other supercontinents, like Rodinia, existed well before Pangaea. Introduce the concept of the supercontinent cycle.

This type of discussion naturally progresses to the mechanics and processes driving the cycle: plate movement. The following resources from the Middle School Portal can help you teach about earth’s interior and plate tectonics. It may also be helpful to brush up on concepts related to geologic time, as these processes span millions of years.

Geologic Time: Eons, Eras, and Epochs

Plate Tectonics: Moving Middle School Science

Once students understand plate interactions (rifting, subduction, sea-floor spreading), take a global view. Using a world map, plot the locations of plate divergence and convergence. Challenge students to predict what the next supercontinent will look like. For example, current plate movement indicates that as the Atlantic Ocean basin grows, the Pacific Ocean basin is shrinking. In the future, western North America may be connected to Asia in the earth’s latest supercontinent. This story from NPR, Amasia: The Next Supercontinent?, tells the possible story.

Introducing Rodinia as part of a greater supercontinent cycle presents plate tectonics as a driving force in a long-term pattern of constructive and destructive forces. It provides another opportunity for students to consider the cyclic change: a fundamental principle in science.

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 msp@msteacher.org. This post was originally written by Jessica Fries-Gaither and published July 24, 2008 in the Connecting News to the National Science Education Standards blog. The post was updated 2/8/12 by Jessica Fries-Gaither.

Newest Issue of Beyond Weather and the Water Cycle Highlights the Science of Climate Study

Scientists recording data on Sperry Glacier. Photo courtesy of glaciernps, Flickr.

The just-published issue of the free, online magazine Beyond Weather and the Water Cycle gives K-5 school teachers a unique opportunity to introduce the science behind weather and climate change to young students with engaging lessons and proven reading strategies.

Each issue of the magazine takes its theme from one of the widely accepted principles of the climate sciences. The theme of the September 2011 issue is “We Study Earth’s Climate.”

Designed to integrate science and literacy instruction for educators in K- grade 5 classrooms, this and earlier issues provide background articles on the related science and literacy topics and their connections to the elementary curriculum. Science and literacy lessons to use in the classroom become a part of unit plans for grades K-2 and 3-5 and are aligned with the national standards for science education and English language arts.

An original story, titled  How Do We Study Climate?, gives young listeners and readers chances to use their comprehension skills on informational text. The story is available at two reading levels and in three different formats.  Selected children’s books on climate and weather are highlighted in a bookshelf feature.

Two articles are devoted to teaching young people to evaluate information from web sites and to use video clips from agencies that work with weather satellites, balloons, and buoys to learn about data collection.

Readers are welcome to add their ideas and suggestions on articles by leaving comments. They can also easily share and bookmark content by using the embedded AddThis buttons.

Beyond Weather and the Water Cycle is funded by a grant from the National Science Foundation (NSF) and produced on the campus of The Ohio State University (OSU) in Columbus, Ohio.  All past issues of the magazine are available from the homepage of the magazine.

Kimberly Lightle, director of digital libraries in OSU’s College of Education and Human Ecology, School of Teaching and Learning is the principal investigator of the project as well as a contributing writer. Jessica Fries-Gaither is the project director of Beyond Weather and the Water Cycle as well as the award-winning sister publication, Beyond Penguins and Polar Bears.


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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 msp@msteacher.org. Post
updated 12/07/2011.

Celebrations of First South Pole Expeditions

This winter will mark 100 years since explorers first reached the South Pole within weeks of each other — Roald Amundsen on December 14, 1911, and Robert Falcon Scott on January 17, 1912. Commemorations, exhibits, and books are expected; some events have already begun and at least one book published.

Norway will celebrate two anniversaries in 2011, Amundsen’s successful expedition to the South Pole and the birth of Arctic explorer Fridtjof Nansen 150 years ago. Some 130 events are planned in Norway and abroad.

British explorers Robert Falcon Scott and Ernest Shackleton and their sponsors were motivated more by scientific interest than the glory of reaching the South Pole first, according to Edward Larson, author of a new book on the expeditions, An Empire of Ice (Yale University Press, 326 pages, $28). With the deaths of Scott and his four-man team on their return from the South Pole, public attention turned more to the courage they showed as they died one by one than to the new knowledge gathered by them and other members of the expedition. Politicians used the deaths as examples of serving one’s country and to rally support for their causes.

A professor of history and law at Pepperdine University and a Pulitzer Prize-winning historian, Larson calls his book “neither a paean to Shackleton’s leadership nor a critique of Scott’s choices.” The publisher says the book “offers a new perspective on the Antarctic expeditions of the early twentieth century by looking at the British efforts for what they actually were: massive scientific enterprises in which reaching the South Pole was but a spectacular sideshow.” Scott, the publisher points out, has been portrayed as a “a dashing incompetent who stands for little more than relentless perseverance in the face of inevitable defeat.”

Most of the 32 explorers Scott took with him were British scientists. They found that Antarctica was a continent not an archipelago, learned that emperor penguins lived on sea ice, and retrieved fossils that would show a warmer climate in the past.

One of Scott’s explorers, Apsley Cherry-Garrard, wrote his own account of the purpose of the expedition, the accomplishments, and the discovery of Scott’s frozen body — The Worst Journey in the World, available online in Project Gutenberg. His worst journey could have been the one he made with the expedition’s biologist, Edward Wilson, to find embryos of emperor penguins. Scientists back in Britain thought the embryos would provide the link between dinosaurs and birds. Cherry-Garrard, Wilson, and Birdie Bowers had to find the penguins in the Antarctic winter (June to August) when the birds incubate their eggs. They had to travel 130 miles to find the penguin colony on sea ice in minus 60 degrees Fahrenheit and build an observation post in a blizzard. Their teeth cracked from chattering in the cold, but they pickled embryos in alcohol and took them back to London.

The three men were the first to witness the emperor penguin’s huddles, its behavior during hatching, and the care the bird gives to the chicks. Cherry-Garrard’s book describes life and work at the base camp in preparation for the South Pole expedition and the long wait for Scott’s return. While some believe Scott’s choices in sledge hauling, clothing, and rock gathering were causes of his return party’s demise, others note that unexpected cold weather (10 degrees Celsius below normal for three weeks) and a blizzard accounted for the team’s inability to reach the nearby store of supplies on the return trip. Otherwise, they would have probably reached the base camp.


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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 msp@msteacher.org.

Beyond Penguins Wins SPORE Award

Beyond Penguins and Polar Bears has been awarded the Science Prize for Online Resources in Education (SPORE) by Science Magazine. The magazine, which is published by the American Association for the Advancement of Science, developed the prize to spotlight the best online materials in science education.

Science editors and a panel of teachers and researchers in the fields select the prize winners. Kimberly Lightle and Jessica Fries-Gaither of the Beyond Penguins and Polar Bears staff were invited to write an essay about the project’s history and goals. The essay, Penguins and Polar Bears Integrates Science and Literacy, appears in the January 28 issue of Science.

Even though the magazine is directed at K-5 teachers, much of the content is applicable to the middle grades. Each of the 20 issues covers science concepts such as rocks and minerals, the water cycle, seasons, states and changes of matter, and plants, all in the context of the Arctic and Antarctica. Each issue highlights a literacy strategy, misconceptions, ideas on integrating technology, the research that is going on at the polar regions, and much more! Project staff have also written informational texts that have been differentiated in terms of reading level. The books are available in three versions – including an electronic version with an audio track. The Stories for Students link in the header of the site will take you to all versions of the books.

Antarctic Pale Ale: Another Use for Icebergs?

A brewery in Australia twice broke the Guinness record for the most expensive beer produced in modern times. The brewery’s secret: Nail Brewing used melted ice from an Antarctic iceberg. According to an article from oneindia News, brewer John Stallwood was looking for new ideas to bring attention to his small operation. His brother-in-law, who works on a ship that sails around Antarctica, took a helicopter crew to an iceberg, dug out some ice, and flew to Tasmania where the ice was melted. Stallwood sold the limited edition Antarctic Pale Ale at an auction to benefit the Sea Shepherd Conservation Society. The ale went for up to $1,850 per bottle. Some 30 bottles of the craft beer were produced.

The oneindia News article drew the attention of Laurel Bacque, who does communications and outreach for the IceCube neutrino observatory project at the South Pole. In her blog she describes the conservation society for her readers, saying its actions have been controversial. The society attempts to stop fishing ships that are hunting whales, sharks, and dolphins.

Icebergs were the theme of a recent issue of Beyond Penguins and Polars. Our columnists see them as a source of freshwater in the ocean, which can raise global sea levels, affect sea circulation patterns, and impact marine ecosystems. You’ll find many resources and amazing photographs for introducing K-5 students to icebergs in this issue – and lots for teachers of all grade levels.