Natural histories

And because it is surrounded by an array of 60,000 photo-voltaic cells, the academy will produce more than five per cent of its electricity and overall use around a third less energy than the maximum allowed by San Francisco's already strict laws. " We could have thought of a different solution for the roof without plants and birds, " says Piano. " But the green roof is about a new spirit for twenty-first century buildings, " he says. " This doesn't mean we have to go back to mud huts with green roofs. We can work with new technology and nature to find the right balance. " The new building has attracted more than four times the number of visitors compared with the old buildings It was the Loma Prieta earthquake in 1989 that determined the academy's need for a new building. Some of the old buildings were badly damaged by the earthquake. Since then, some of the old buildings in the Golden Gate Park have been restored while new buildings, such as the De Young Museum, have been added to the site. The new academy has also had to meet tough regulations in the event of a future earthquake. And the new academy building has proved an instant crowd pleaser. Its clear glazed walls reveal some of the attractions inside, notably the two great spheres of its planetarium and artificial rainforest. The dramatic four-storey rainforest offers a vertical journey through four different rainforest habitats. From outside the building, its design means that you can see straight through to the park from almost any angle. From its opening at the end of September until early November, the new building has attracted more than four times the number of visitors, compared with the old buildings when they were last open over the same period in 2003, says Michael Ng, a spokesperson for the academy. And a new space where researchers at work can be observed by visitors behind a glass screen has proved very popular with the public, he says. " And many of the scientists enjoy the experience too. " The new academy is one of ten pilot 'green building' projects of the San Francisco department of the environment, part of an initiative to develop models for workable, sustainable public architecture. Life science: A growing coral reef is just one of the many remarkable displays on show to visitors to …