Does It Make Scents?
OBJECTIVES: The students will be able to describe how a mother bat finds her baby among the other baby bats.
BACKGROUND: Grey bats group together in nursery colonies to have their young. With so many bats crowded into a small area, the temperature in that area can be raised up to 90 degrees or more. The mother bat leaves in search of food and the pups will huddle together, as many as 500 baby bats per square foot. Upon returning the mother can find her own baby by using her senses of smell and hearing.
MATERIALS: Cinnamon oil, clove oil, mint extract, vanilla extract, lemon extract, witch hazel, any other distinctively scented but safe fluids, construction paper, yarn, scissors, blindfold, tin clicker ("cricket") if available.
1. Explain to the students what a nursery colony is. Ask them how it may feel to live in a bat colony.
2. Have each student draw a bat on the construction paper and cut it out. Using the yarn, make a necklace from the paper bat. Designate 5 students to be adult bats and the rest of the children will be pups. Without the children watching (you may want them to leave the room), place a couple of drops of cinnamon oil onto one of the adult bats. Using the same oil, place a couple of drops onto one of the baby bats. For the second adult bat, use clove oil. Place a couple of drops of clove oil on a baby bat. Use the mint, vanilla and lemon extract for the remaining three adult bats and corresponding baby bats. Use the witch hazel to scent the remaining pups. Allow them to dry for several minutes.
3. When the students return, tell them you have put scent on their bats, and they are not to discuss their scent with other students. Separate the "adults" from the "pups". Have each student put on their bat necklace. On one side of the room have the pups line up against the wall. On the other side of the room, blindfold one adult. Tell the adult to walk across the room and find the pup that matches his/her scent. Record how long it takes to find the matching pup. Next, blindfold the second adult and repeat the process. Continue until all the adult bats have found their pups and the times have been recorded.
4. Have the students trade necklaces in order to have 5 new adults and different pups. Pair each adult with its correct pup. Have them figure out a special click (or clap) for the pair.
5. Have the pups go to one side of the room. Blindfold the first adult on the other side of the room. Mix the pups around. Have the pups do their special click quietly. The adult will try to find its pup by using not only scent but also sound. Let each adult be blindfolded and find its pup. Record the time it takes for the adult to find the pup. Is it quicker than with just smell alone?
6. Have the students once again trade necklaces. Pair the adults with the correct pups and once again ask them to agree upon a click sound. Allow the adults to place their pups along the wall. All the other pups can then pick a spot along the wall. The adult is then blindfolded and sets off to find the pup using smell, hearing (the clicks) and memory. Allow each adult to find its pup. Record the time it takes for each adult to find the pup. Is it quicker than the previous ways?