Echolocation Experimentation: Can You Hear It?
How do dolphins use echolocation?Copyright Stephen McCulloch, HBOI, Southeast Fisheries Science Center, NOAA http://www.sefsc.noaa.gov/species/mammals/photos.htm
Students drop marbles into holes cut into shoebox lids and listen carefully to try to determine the materials inside the box that the marbles fall onto, illustrating the importance of surface composition on dolphins' abilities to sense materials, depth and texture using echolocation. This activity builds on what students learned in the associated lesson about bycatching by fisheries and how it affects marine habitats and species, especially dolphins. Students learn how echolocation works, why certain animals use it to determine the size, shape and distance of objects, and how people can take advantage of dolphins' echolocation ability when developing bycatch avoidance methods.
While dolphins use echolocation to identify the presence of objects, they have difficulty identifying nets, and thus often become entangled in them. Engineers apply their understanding of how dolphins use echolocation to design nets and other techniques to minimize accidental dolphin catch by making nets easier for dolphins to "see." Engineers are often inspired by concepts in nature, such as submarine sonar as a type of echolocation.
After this activity, students should be able to:
- Explain how echolocation works.
- Describe how different surfaces sound when impacted and how this relates to echolocation.