Summer SAVY, Session 3 Day 3, Dabbling with DNA (Schott) (3rd – 4th)
Today, we were busy. We started with a getting-to-know-you activity and a review of the previous days. Then, we began our study of evolution with a short video about the life of Charles Darwin and the idea of evolution via natural selection. (They learned about using the word “via”.) We talked about adaptations and what it means for a trait to be adaptive. This included a brief field trip where we were amongst the trees, and they made observations of different organisms including plants, ants, squirrels, and this thing…
We think it’s in a group of insects known as the leaf-footed bugs. I let it crawl on my hand to demonstrate that it was harmless, and many of the students wanted to have it on their hands. They did a great job figuring out how these various organisms are adapted to their environment. Before lunch, we started a computer simulation of natural selection with hypothetical critters and a changing environment. They ran the simulation several times and saw that they didn’t always get the same outcome. Sometimes, there was a disease outbreak or a drastic change in the climate or their species may have gone extinct. They will probably want to tell you about the “computer game,” so be sure to ask them!
After lunch, we finished the computer simulation and connected evolution via natural selection to genetics and genetic mutations. We discussed the example of the evolution of lactose tolerance in humans. We finished the day with the students brainstorming about artificial selection and coming up with examples of species that exist because of artificial selection. They gained an appreciation of the degree to which people have modified species and learned about the idea of a trait being maladaptive. Here, we talked about breeds of dogs with problematic traits, such as the flat faces of pugs and bulldogs and the fact that bulldog pups are often born via C-section. We added many terms to our TIP sheet, and I think they enjoyed the day. Encourage them to consider the world around them–how natural selection has shaped our world and how we have shaped the world via artificial selection. What do pets have that are adaptive? What traits are maladaptive? If they were going to create a breed of dog, what traits would they want in that breed?
We look forward to seeing everyone again tomorrow!
