Making a rock mold usually requires a three- or four-person crew and 50 to 80 gallons of liquid latex, which is brushed onto the rock in layers, between layers of cheesecloth. Each layer is allowed to cure before being covered with the cheesecloth. Then a "jacket" of poly-urethane foam is sprayed on to make sure the latex holds its shape. Seven days later, when the latex covering is dry, workers peel it off, producing a mold with the exact contours of the rock. Taplin says it takes about 10 days to make 15 to 20 molds, each of which can yield 200 rocks.
To create a banyan tree for a rain forest exhibit, workers begin with a 20- to 40-foot-long column of steel mesh, over which they spread a yellow epoxy mixture that resembles cookie dough. Then an artist painstakingly etches into the epoxy a network of cracks and scratches that mirror those in the banyon tree photographs posted on a nearby bulletin board. A second artist presses a textured pad of rubber against the mixture, and when he pulls it away, the epoxy has the feel of real bark.
The best proof of the replicas' authenticity comes from the animals who live among them. At Tucson's Arizona-Sonora Desert Museum, margays, rare spotted cats from Central and South America, roam over the elaborate Larson-made rock habitat as if it were home. At the Bronx Zoo's Jungle World, gibbons swing on Larson's rubber vines and crawl over its steel and epoxy trees as though the vegetation were the real thing.
Because contented animals are better breeders, well-crafted habitats may help save some species from extinction. The only group of proboscis monkeys in captivity in the Western Hemisphere live in a Larson environment at Jungle World. They flourish there, as do tapir, langurs and gibbons.
"Proboscis monkeys are especially difficult to keep in captivity," says Doherty, "but we have a lot of space, we feed them a good diet and they're breeding very well. A good exhibit is part of what keeps the animals content."
Donald Kuenzer, senior curator at the Cleveland Metro Parks Zoo, believes visitors also benefit from such exhibits. "Nobody wants to see an animal sitting on a concrete shelf in a cage," he says. "People want to see natural-looking things."
Pleasing visitors has a larger value. As Dick George, spokesman for The Phoenix Zoo, says, "If visitors can look at animals in an environment reminiscent of nature, in which the animals are active and enjoying life, they leave thinking the animals are wonderful creatures. They have a heightened sense of respect, which helps the conservation effort."
One of Larson's newer fakes, a saguaro cactus, might ease a problem closer to home. Recently cactus rustlers in Arizona and California have been digging up the giant desert plants and selling them for thousands of dollars on the black market. If enough homeowners and commercial developers begin using replicas of Arizona's signature plant in their landscaping, the rustlers' market could shrink considerably. Larson's saguaro is made from a length of PVC pipe wrapped in foam and covered with fiberglass. It comes complete with a bird hole, fabric and urethane flowers, and cactus needles that are made of bristles from a push broom.
It is fitting that Larson has branched off into saguaros because the company traces its roots to the Sonoran Desert. The company's founder, Merv Larson, was a curator at the Desert Museum, where many of the early habitats he designed are still in use. He left the museum in 1976, and with Taplin helping him, began manufacturing replicas on his own. Five years ago Larson sold his interest in the company—which has 250 employees—to a group of investors.
Part of the company's growth is a result of good timing. As more laws protecting natural habitats have been enacted, the demand by zoos and aquariums for imitation products of nature has risen, especially in the case of coral.