More than a thousand exotic butterflies flit among tropical flowers and plants in a vaulted, glass building. Some perform the delicate ballet of courtship, others feed from trays of overripe fruit or sip nectar from flowers.
Inside the St. Louis Butterfly House - an 8,000-square-foot atrium - a perpetual summer provides the ideal warm, humid habitat for butterflies. A southern exposure gives the cold-blooded insects - and their visitors - maximum sunshine.
Since butterflies have the widest range of color vision in the animal kingdom, visitors who wear bright colors are most likely to attract the insects.
Known officially as the Sophia M. Sachs Butterfly House and Education Center, this is the ninth year-round butterfly house to open in the US since 1988.
"Butterfly houses are a relatively new phenomenon," says Frank Elia, director of the center.
The first public butterfly house opened on an island in the English Channel in 1976. Since then, more than 300 enclosed butterfly habitats have been built from Melbourne, Australia, to Vienna.
Most are associated with zoos, museums of natural science, or botanical gardens. The St. Louis Butterfly House is only the second in the US to be a nonprofit, stand-alone facility.
The proliferation of butterfly houses is getting more and more people interested in butterflies.
"Over the last 10 years, there's been a sea change in the way the public views butterflies," says Jeffrey Glassberg, president of the North American Butterfly Association in Morristown, N.J. "More and more people see butterflies as wildlife, and they are going to butterfly houses like they go to zoos. That often ends up involving people with butterflies in the real world."
The facility here, which opened last month, includes a learning lab for classes of all ages, an outdoor garden showing visitors how to attract butterflies to their own backyard, and a teaching garden where demonstrations and classes are held.
"We can teach people a lot with butterflies because they're so accessible," Mr. Elia says. The global message of environmental conservation is communicated inside where majestic butterflies from around the world mingle with visitors. Their beauty and symbolism are universally recognized, yet few people understand much about how these insects fit into the ecosystem.
Outside the building, Elia says, we have a local message about how to make your own corner of Earth more butterfly-friendly. "We want everyone to look at their own backyard as a habitat for butterflies," he says. "The goal is to put butterflies in the scheme of things," explains Ellen McCallie, curator of education. For example, many people don't even realize that killing caterpillars with insecticides destroys butterflies. Making those connections for children and adults is important, Ms. McCallie says.
For Evelyn Newman, the philanthropist who first conceived of a butterfly house in St. Louis and raised the funds, the effort is about "welfare of the spirit and psyche." "Butterflies are such a wonderful symbol of the mystery of life taking place before your very eyes," she says.
Many visitors to the St. Louis butterfly house are getting a glimpse of the magic of metamorphosis. One corner of the atrium holds a glass case where hundreds of chrysalides hang waiting to open and release a newcomer.
All the butterflies here come from overseas. The caterpillars are raised on farms in the Philippines, Malaysia, Costa Rica, and Ecuador and shipped once they are in the chrysalis stage. Most spend three to five days hanging on display in the butterfly nursery before making their debut. After their wings unfurl and dry, Mark Deering, curator of butterflies, opens the glass doors and lets the new arrivals onto the main stage.