Dyan Branstetter | March 2016
Spiders: Nature’s Musical Tuners
Have you ever stumbled upon something so amazing that you just have to bring it into your classroom? Here’s what I learned today: spiders “tune” their webs like string players tune their instruments. Since I began truly integrating the arts, a switch has flipped in my mind that challenges me to test any concept, or topic for arts-integration-ness. Sometimes, I want to connect a standard that might be an academic challenge for my students, but I can’t find that natural arts connection. This makes hearing about spiders as nature’s musical tuners is enough to make my mind explode with integration anticipation because it is just so perfect!
Here’s a summary of the amazing science, from NPR:
A spider’s silk strands on its web vibrate like strings on an instrument. Just like a musical instrument’s strings’ thickness and length determine its pitch when plucked, a spider’s web does as well. Spiders as musical tuners can sense this from sensors in their legs. The golden orb spider can even identify different vibrations or pitches moving on its web. If that’s not enough, spiders as the musical tuners are able to fine tune the strands of the web by tightening or loosening to change the way it resonates. This gives the spider information about where their meal is tangled. If the web is not “tuned” correctly, the spider can’t determine where the tangled insect is. The spider as musical tuners even causes vibrations to interpret echoes that help it locate its prey. Pretty amazing for a more or less brainless arachnid. Watch a video clip here: https://www.youtube.com/watch?v=0EkEsTafD38&feature=youtu.be
This ties in perfectly with standard 1-PS4-1 from the Next Generation Science Standards (NGSS): Plan and conduct investigations to provide evidence that vibrating materials can make sound and that sound can make materials vibrate. It also fits perfectly with Grade K-4 Music Standard 8: Understanding relationships between music, the other arts, and disciplines outside the arts. And there lies the integration: Content Standard + Arts Standard.
There are three easy ways I have found to have students experiment with sound. I typically do this in stations so that small groups of students can have easier access to the materials, and I can float from group to group to facilitate. For maximum inquiry, allow students to explore each station, noting observations without the T-chart categories mentioned below. After exploration, have a discussion to come to the conclusion about the relationship between the length of the string or band and the pitch.
It takes time to train students to inquire and observe in a scientific way. If your students (or you) are not ready for the loss of teacher control over the inquiry, provide the students with guiding questions at each station to lead them to what you’d like them to discover.
Preparation: Turn a wire clothes hanger upside down. Cut two pieces of yarn no shorter than 12”. Tie a piece of yarn to each corner. Create other “hanger bangers” with varying lengths of yarn so that students can investigate the relationship between the length of string and the sound.
To use, wrap each piece of yarn around your index fingers like dental floss and plug your ears. Lean over and bump the hanger against different objects. Have students record observations on a T-chart labeled length and pitch. (This clip has the same idea, but with spoons: https://www.youtube.com/watch?v=frTUMP9KPpo)
Rubber bands of varying lengths and widths
Small cardboard boxes of varying lengths
Have students carefully stretch a few rubber bands around an open box. Pluck the strings to observe the relationship between the length and pitch. Record on a T-chart labeled length and pitch. (More technical tips here: https://www.youtube.com/watch?v=b-Oocwv_HUU)
Dancing on the Drum
Prep: (Wrap paper or a balloon over an empty can to make a “drum”)
Place a few dried beans or paper clips on top. Have one student tap on the drum and observe the beans (or clips) jump.
Extension: For older grades, you can demonstrate sound waves with a slinky stretched between two students. After experimenting (playing) with making waves, teach the wave vocabulary words. Make the slinky wave again to see the vocabulary words in action, and then sketch a label. (See examples here: https://www.youtube.com/watch?v=kxQj-wPePBU)
For further music connections, share clips of string instruments, especially of instruments being tuned so that students can observe how tuning tightens or loosened the strings, therefore changing the pitch. Brings us full circle back our musical tuners spiders!
Assessment: Have students respond in writing to explain the relationship between length and sound.
Literature Connection: Spiders and Their Webs by Darlyne A. Murawski (http://www.scholastic.com/teachers/book/spiders-and-their-webs#cart/cleanup)