I call students to the gathering area. We review how light travels and how it interacts to barriers it encounters. I tell them today, we are going to look at how animals use their eyes to process light information.
I read students the book, “Alien Invaders” by Lynn Huggins-Cooper. This book is about a boy who sees space aliens all around him. He describes their shiny robot legs, helmets, and shiny suits, and their camera-lens eyes. His mom tells him that they are just bugs, but he decides to make friends with them “just in case.” This book features a great fictional story of how funny bugs look, and also features very exaggerated pictures of different bugs. These are great discussion-starters, for looking at insect eyes.
After reading, we do another picture walk through the book. I ask students to pay special attention to the different eyes that they see. I ask students to make observations and then try to infer how the insect might be able to use their eyes to process light information and see in an efficient manner.
I ask students if they have ever tried to catch a fly. If they have, I ask what happens when you get close to a fly? It always seems to get away right before you catch it. It doesn’t matter which direction you come at it from. I ask students if they know why the fly might be able to do this? It is because of the design of its eye. The fly does not have a blind spot like humans do. I tell students that today we are going to build a model of an insect eye.
I put students into groups of 2-3 and provide them with the materials they need. They receive a paper bowl, an egg carton for 12 eggs, scissors, and a sheet of bubble wrap, glue and tape.
Students cut the individual egg-cups apart so they have 12 individual cups. They invert the paper bowl and attach the cups to is with the opening of the cups facing down. Each group cuts 12 hexagon-shaped pieces of bubble wrap to attach to the bottom of the egg-cups. These are the lenses.
When students have completed their compound eyes, I call them back to the gathering area. We look at our models and discuss the similarities and differences between our eyes and this compound eye. There are lenses on both, but humans only have one per eye, flies have multiple facets and each facet have multi-directional lenses. The fly can see almost 360 degrees without moving its head. No wonder it is so hard to catch!
To preview the next set of lessons, I ask students, what other body features they think might assist an insect in its survival?