The Crochet Coral Reef

The Crochet Coral Reef, Mathematical Yarn, and Fringe Physics with Margaret Wertheim

I attended a guest lecture by Margaret Wertheim, science writer and exhibition curator. She gave a presentation about her life work combining art and science. This includes her scientific museum in Los Angeles, called the Institute for Figuring (The IFF). She also told the inspiring story of the Crochet Coral Reef and how her living room project turned into a global environmental phenomenon.

You might have heard about the Crochet Coral Reef project during its burst of popularity between 2005 and 2009. Margaret and her sister, Christine, started the project to raise awareness of how coral reefs become ill and die as ocean temperatures rise. They made models of coral reefs by hand using crochet (cro-shay), which is a way to weave yarn using a single metal hook. It’s like knitting, but more versatile. They hoped the models of crochet coral would remind people how beautiful the reefs are and how sad it would be if the reefs were to disappear. They didn’t realize that their personal art project would become so popular, shown in many museums and inspiring offshoot reefs by other crocheters too.

You can learn more about the Crochet Coral Reef here. This was a fun way to start the lecture, with lots of pretty pictures of coral on the powerpoint slides. But what made the lecture even more exciting was the mathematics that inspired it all . . .

Margaret and Christine didn’t set out to crochet a coral reef originally. They were in their living room, practicing hyperbolic crochet. Hyperbolic crochet is different from regular crocheting, because normally you crochet a constant number of stitches. But in hyperbolic crochet, you sometimes add an extra stitch, which increases the amount of yarn in the fabric, making it wavy and ruffled. In mathematics, this is called a hyperbolic surface. Different hyperbolic surfaces can be made with different crochet “algorithms” which tell you how often to add stitches.

There is an entire field of hyperbolic geometry (a younger branch of mathematics, less than 200 years old), which studies the properties of these surfaces. Hyperbolic crochet was recently invented by Daina Taimina of Cornell University as a way to visualize hyperbolic geometry, since it is usually so difficult to describe. This is what the sisters were working on when they realized how much their handiwork looked like a piece of coral. The reason it looks like coral is, coral itself actually grows in hyperbolic shapes. The “ruffles” of a hyperbolic surface let lots of water flow across their increased surface area, which helps coral get more nutrients. Nature can evolve some pretty high level mathematics!

The sisters kept working on their project until it was big enough to fill museum exhibits. Since then, three million visitors have seen their handiwork in the exhibits, and over six thousand people have helped crochet more pieces to display all over the globe. The crochet coral reef brings awareness to global warming and preserving the beauty of nature. (To learn even more, click here!)

While the coral project is still going on, Margaret Wertheim has moved on to new projects. Her own museum, The IFF, is a “play tank” for visitors to discover cool math and science facts in a hands-on way. It even hosts workshops for people to build and play with materials, and find out how the world works. I hope I can visit soon! Another project is her most recent book, Physics on the Fringe, which is about alternative theories of the universe dreamed up by amateur scientists. Apparently, even with no university training, people all over the nation sit at home and invent alternate explanations for big ideas, like gravity.

Tying all these threads together, I am glad that Margaret came to talk to us about crocheted coral, mathematical yarn, and fringe physics. Puns intended. Her lecture brought together my favorite art (crochet, all the way) with math, biology, and physics. Who knew that art and science could intersect so closely?