Calvert – Fossil footprints

Hello Garden Friends,

This week we had a special class for several reasons – Last day with the second graders, introduction ofCalvert - May 6, 2016 - 5 of 5 new intern ranger Jessica, special cooking lesson, ANNNDDD our wonderful garden parent Paul Cassell surprised us with new shelves and a white board in the tool shed! Thanks Paul! With the whiteboard we can increase communication between Enrich LA team and the school’s volunteer community.

Anyhow, the lesson! Last Friday at Calvert the second graders learned about fossils. Most of the students roughly knew that they had to do with bones and rocks, and dinosaurs that lived a long time ago. This was all very helpful when trying to explain that scientists study fossils to figure out how all living things are related. “Did you know that we are all family?” I asked. “Yes, the great apes and dogs are family too, though dogs are more distant relatives.” I continued that by looking at the similarities of our bone structures and how they evolved over time, we can make educated guesses about when we shared a common ancestor with a particular species, like a dog. The activity that followed showed the students how plants can make fossils.

Calvert - May 6, 2016 - 1 of 5 Before class Jessica helped me mix 1 cup of corn flour (called masa), and 1 teaspoon of salt into 1 cup of water to make the dough. Then, I held up a ball of dough over my head. “Imagine, this is a rock resting on the top of a mountain.” I slowly brought the rock down to chest height, “Over time, the rock breaks down into soil by rain and wind and settles on the valley floor.” I shmush the dough flat into my hands and press a leaf into its surface. “Sometimes, a tree falls or a dinosaur dies and its body gets covered with soil from a flood or volcanic ash – and when this happens the body is compacted and pressurized into a fossil.” Finally, I compost the leaf to make it extinct and show the class the imprint of the leaf on the soil. “If we study the rock and figure out how old it is, we can see how long ago the plant lived even if its body no longer exists.”Calvert - May 6, 2016 - 2 of 5

After repeating the instructions and passing out materials, the students had a chance to make their own and seal the imprints in place by cooking it on my cast iron. In the featured image you can see Jessica whipping together the tortillas for the students.

As we came together at the end of class, and the students were enjoying their edible fossils, we talked about the human imprint on our landscape. “What do our fossils look like? Do we leave anything behind besides bones?” I was trying to teach the students about our carbon footprints and how the consumption of plastic goods litters our soil for hundreds if not thousands of years. Note for next time, maybe leave the existential human legacy lessons to the 4th and 5th grade students. I left them with a final thought and simpler message – “Have a great year, visit me during recess, and let’s leave the earth better than we found it.” 🙂

Until next time,

Jeff Mailes