Some of the wonderful students at Greenbrier. Evan in the red shirt.

I was invited by one of our grandsons’ teachers to visit her 7th grade life science class at Greenbrier Middle School, Evans, Georgia (about 15 miles west of Augusta). I had not taught a lesson for a group of 7th graders in a long time, so this was going to be a challenge. When I received the phone call from 12 year old Evan, he told me that he mentioned to his teacher, Mrs. Susan Weiksner, that I was a professor, and had even written a book! Fast forward to yesterday. My wife, Mary-Alice and I arrived at the school at 11:30 for a 12:20 – 1:20 class session.

We met the media specialist, and she helped me set up the technology. I prepared a Powerpoint Presentation and developed a website for the students as a follow up to the lesson.  You can visit the website to read about the content of the lesson, see slide shows on Darwin, the geology of Georgia, fossils, and pictures taken by Mary-Alice of the students in action during the lesson. Please follow this link.

Mystery at the Ringgold Roadcut: Fossil crinoid stems from Taylor's Ridge, near Ringgold, Georgia.

All was ready for the 40 students who arrived about 12:15, each carrying a backpack of at least 50 lbs. of books.  Mrs. Weiksner had combined two classes for the presentation. We were ready to go.

For the lesson at Greenbrier, the focus was on how Charles Darwin used fossils, as well as his finding and discovery about the age of Earth to help him create biology’s most important idea, the idea that life on Earth has evolved through natural selection. For Darwin, the development of this idea took many years, starting with his five year voyage of the HMS Beagle.  After his voyage, and after publishing his first book, The Voyage of the Beagle (an absolutely beautifully written book about geological and natural history of the many areas he visited), Darwin began the task of working with specialists in biology and geology to identify the huge collections he had sent back to England.  He kept his ideas in “secret” notebooks, and then in 1842, wrote his paper on his ideas on the origin of species.  But, he put the paper away, and asked his wife, Emma, to publish the paper should he die, and even set aside about £100 to pay for the publication.

As the students learned during the class, Darwin, at this time, wasn’t the only one who discovered this important idea. Alfred Russell Wallace had also arrived at the idea that species evolved through natural selection.  Darwin received a letter from Wallace in 1858, and was shocked to read Wallace’s paper which described the same ideas on evolution that Darwin had written 14 years earlier.

Tomorrow is the 200th anniversary of Charles Darwin’s birth, and I used it as a way to connect to the class by asking if anyone had a birthday this week. One of the student’s birthday was the 12th of February, and another student raised her hand to inform us that it was her father’s birthday on the 12th. She wanted to be involved. I asked both of them to come to the front of the class to help me with a demonstration of the geological time scale using a length of rope.

Using a length of rope, we talked about the age of earth and the geological time scale.

We had planned three activities to help the students see how fossils were important to Darwin, and to also show that Darwin used geology as as an important aspect in the future development of his theory to explain how species changed over time. Here are the activities we did.

Mystery at the Ringgold Road Cut. In this activity, the students were given a bag of crinoid stems that I had collected from lower Paleozoic rocks in Northwest Georgia, a hand lens, and a metric rule. They were asked to investigate the objects, and use observations of the fossils to pose questions, and make conclusions about what they thought the objects might be.

Being a Palentologist. Into brown paper bags, we put a fossil and a geological time scale that included drawings of organisms associated with the three geological eras. Students picked up a bag, and then proceeded to use their powers of observation to try and interpret when the fossil might have lived and in what kind of environment. When they had an idea, they could pick up a sheet of paper with further information about their fossil from Mary-Alice. Fossils included: brachiopod, oyster, petrified wood, shark tooth, amber, coprolite, fern, fossil fish, trilobite, sea urchin, dinosaur bone.

Coprolite: fossilized poop. One of the fossils used in the "being a paleontologist" activity.

The Footprint Puzzle. We provided the students with a footprint showing two sets of fossil tracks (of dinosaurs). The students used the tracks to discuss what they thought might be going on. In the map of the tracks, the tracks converge and at the point of convergence, there tracks overlap each other. After some discussion, students make the inference that there were two dinosaurs, and they met up, and either mated, or had a fight. When then provided them one additional piece of information. The additional information showed only one set of tracks exiting the area of convergence.

Dinosaur footprint puzzle

We used images of Darwin’s voyage around the world, images from Down House, Darwin’s family, a picture and reading of the letter he received from Alfred Russel Wallace in 1858 that shocked Darwin into making his theory of natural selection public, and indeed, his and Wallace’s papers were read at the Linnean Society in London in 1858.

It was a wonderful day with the students. They eagerly involved themselves in the activities, and worked with each other. They asked interesting questions, and talked knowingly about fossils and evolution.

One of the students discussing his group's fossil in the "being a paleontologist" activity.