Summary:
Today was the Unit 4 Test, and overall the scores looked good. Questions covered everything from Darwin’s Theory, to the evolutionary tree, to modern examples of evolution. The open response section asked students to use what they learned during the Of Spice and Men project and apply it to a real-life scenario: testing a new antibiotic called zibloxyn.
Resources:
February 2 – Unit 4 Test (pg416).docx
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Summary:
Today was our final day before the Unit 4 Test. It was a half day, so we simply played a review game (based on the famous shell game) to help study. The topics I emphasized included Darwin’s Theory, the evolutionary tree, and evolutionary trade-offs, since those topics where all from a few weeks back. To see the game in action, check out the video above. Tomorrow we will wrap up our study of evolution with the Unit 4 Test.
Resources:
None
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Summary:
Today was the final day of the “Of Spice & Men” project. Students worked on their lab reports, and we finally got to the question we’ve been pondering all along: “Why do we humans like what we like?”
Imagine that there were three families of cave men living together on an island. The first family had a genetic trait that caused them to like the smell of pine bark, so they began to experiment with grinding it up and sprinkling it on their food. The second family had a trait that caused them to prefer cinnamon bark, so they began to sprinkle it on their food. And the third family preferred their food plain.
Which family would die off first? According to our results, the “pine bark family” would be in rough shape. Pine bark might even promote germ growth, so that family would probably be exposed to several diseases. Cinnamon, on the other hand, kills germs. The “cinnamon family” would have an advantage over the “plain family.” By sprinkling cinnamon on their food, they would actually kill germs, which would make their children healthier, stronger, and less likely to get sick. Over time, the “cinnamon family” would take over the island, perhaps even passing off their cinnamon-loving genes to members of the “plain family.”
That’s evolution, my friend. And that was the main take-away from this project. The reason we enjoy the tastes of things like cinnamon, nutmeg, and mint is because they all kill germs! And over thousands of years we have evolved to like their flavors. In fact, the vast majority of spices have germ-killing effects. Garlic, oregano, cloves, rosemary… we don’t just like them by accident. We have evolved to like them.
Resources:
January 25-31 – Of Spice and Men (pg415).docx
Of Spice and Men Example Lab Report.pdf
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Summary:
Today we finally got to observe what was growing in the boiler room for the past three days. Needless to say, it wasn’t pretty. But it sure was educational.
By comparing the germ growth of different agar plates that had been covered with different plants and spices, students were able to determine each plant’s germ-killing effect. Cinnamon killed the most germs by far, followed by nutmeg, and mint. The five other plants (pine bark, oak bark, leaves, grass, and pine needles) did not have any germ-killing effects. So what does it all mean? And how is all of this tied back to human evolution? That is the topic for tomorrow’s lesson.
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Summary:
Today was the third day of the “Of Spice & Men” project. Students took their agar plates out of the fridge and got to work trying to figure out how to solve this mystery. Remember, the goal of the project is to “measure the human preference for the tastes of different plants and compare it to each plant’s germ-killing effects.” But the big-picture question we are trying to answer is “Why do we like what we like?”
Students took their agar plates and added germs from their saliva to each one. After that, it was time to add the spices. Most groups chose to cover half of each Petri dish, so they could compare germ growth in the empty half of the dish to germ growth in the spice-covered half of the dish, thus building their control group right into each test. The students could then use their separate dishes to compare mint leaves to regular leaves, cinnamon bark to pine bark, or any other combinations they could think of. Tonight, Mr. A will store the dishes in a warm, dark location. We will then let the germs grow for three full days. On Tuesday, we will observe our results.
Resources:
January 25-31 – Of Spice and Men (pg415)
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Summary:
Today was the second day of the “Of Spice & Men” project, and it was really more about prep work than anything else. Students started off by making a hypothesis about which plants/spices might have germ-killing effects. Then, they set about making agar plates, which are gel-filled Petri dishes that you can use to grow microorganisms. In other words, they are like “germ-food Jello.” The agar plates are being refrigerated overnight. Tomorrow, the students will add germs and spices to the dishes. And after we let them grow over the weekend, we should finally be able to solve this mystery, once and for all!
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Summary:
Today was the first day of our “Of Spice & Men” project. The goal of the project is to measure the human preference for the tastes of different plants and compare it to each plant’s germ-killing effects. The essential question behind the experiment is one that baffled scientists for centuries. Why do we enjoy the tastes of mint, cinnamon, and other herbs & spices, when they offer little nutritional benefit?
We began with a PowerPoint (posted below) that introduced all of the different components of the project. We started with the big-picture question: Why do we like what we like? Then we discussed the history of spices, some information about germs, and how scientists experiment with germs using Petri dishes, agar, etc. At the end of class, we measured the human preference for the different plants we’ll be testing using a simple classroom survey. Students smelled eight different spices and rated how they thought each one would taste, on a scale from 1 to 5. No surprise here; cinnamon had the highest rating.
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