WHO NEEDS ANEMONES? Crocheted coral raises awareness and eyebrows.

Photograph: Aaron and Cassandra Ott/Institute for Figuring

Some people help the environment by reusing grocery bags or driving a Prius; Margaret Wertheim uses crocheting needles. Along with her twin sister, Christine, the 49-year-old Los Angeleno helms the Hyperbolic Crochet Coral Reef Project, a handicraft-science hybrid that raises awareness about the world’s disappearing reefs through weird, woolly simulacra. Starting Monday 7, the World Financial Center’s Winter Garden will showcase thousands of feet of the project’s crocheted coral, sea urchins, kelp and the like. (A smaller display unfurls at NYU’s Broadway Windows on Sunday 6.)

Born in Queensland, Australia, the Wertheim sisters have long been concerned with the future of their homeland wonder, the 135,000-square-mile Great Barrier Reef, which is under constant threat from pollution and rising temperatures. But “hyperbolic crochet”—a method of re-creating, through knitting, the natural surface patterns found in coral and other crenelated organisms—was only discovered in 1997 by Cornell researcher Daina Taimina. “Mathematicians thought you couldn’t reproduce hyperbolic geometry, but Daina showed you could do it with crocheting—if you increased your stitch at a steady rate,” explains Margaret, a science writer by trade. Along with Christine, she’s also a founder of the Institute for Figuring (theiff.org), which explores artistic applications for science and math.

The twins used Taimina’s formula for some time, but monotony took its toll. “One day Christine shouts, ‘I’m sick of mathematical perfection!’ and started making her stitches more random, which made the pieces look a lot more organic,” says Margaret. “Nothing in nature is ever perfect.”

In 2005, the pair started training a core group of 15—mostly conservationists who learned to crochet­—and a hobby blossomed into activism. Then it became something of an obsession: “These little fluffy things have taken over our lives; it’s like something out of ‘The Trouble with Tribbles’!” jokes Margaret. “We’ve got probably 3,000 models now.” The smaller, one-inch pieces can be completed in as little as 30 minutes, but larger models take substantially longer. (Christine has been working on one for three years.)

Both the art and preservation worlds have taken notice of the project, with institutions like Pittsburgh’s Andy Warhol Museum and the Chicago Cultural Center hosting exhibitions. A reef made of textile coral sewn by Windy City activists will be on display at the World Financial Center show, as will one crocheted by a group of 100 New Yorkers (some seasoned crafters, others new to the trade) and a yarn-and-trash model called the Toxic Reef. “People ask if this is art-and-crafts or science or consciousness-raising or a feminist statement. It’s all of that—that’s the beauty,” says Margaret.

Also on view in the Winter Garden is Helle Jorgensen’s Rubbish Vortex, a crocheted-plastic-bag representation of the Great Pacific Garbage Patch—a floating garbage dump that’s been accumulating man-made detritus in the middle of the Pacific Ocean since the 1950s. (It’s currently twice the size of Texas.) “Coral reefs are under stress—we’ve got to get the message of conservation out there,” says American Museum of Natural History marine biologist Kate Holmes, who will join Margaret at a lecture at the AMNH on Tuesday 8. “The crochet project takes a new and interesting twist by looking at the mathematics of coral. It’s another entrance point…and it allows us to involve craftspeople who might not be into conservation.”

Margaret is confident that with two New York shows and an upcoming exhibit in London, her and her sister’s efforts are resonating with an increasingly eco-conscious public. “The crocheted reef will have a long lifespan,” she predicts. “But let’s hope not longer than the reefs themselves.”

The Hyperbolic Crochet Coral Reef is on display at the World Financial Center Mon 7–Aug 31, 2008.