Online retail giant Amazon has opened the centerpiece of its new US$4 billion headquarters in Seattle. Consisting of three giant interconnected glass and steel balls, the Spheres blur the lines between workplace and conservatory by combining an open work environment with the surroundings of a mountain tropical rainforest garden, complete with trees over 40 ft tall.

Amazon is noted for its openness to innovation and the company's new downtown campus reflects this. Along with about 40 more conventional glass box buildings that make up much of the sprawling campus, the company decided to add something a little different.

Based on a studies indicating that workplaces that provide a direct link to nature spur creativity, the Spheres are home to 40,000 plants made up of over 400 often rare species from botanical gardens, tree nurseries, and conservation programs from five continents and 50 countries.

Most of these plants were selected from cloud forest ecosystems. These are plants that do well on cool, moist mountainsides from 3,000 to 10,000 ft and take their water directly from the air. And we're not talking flowerbeds here. The biggest specimen is a Ficus rubiginosa named "Rubi" from a California tree farm that stands 55 ft (17 m) tall and is 22 ft (7 m) wide.

To help keep the interior temperature at 72° F (22° C) during the day and 58° F (14° C) at night, the 2,643 panes of glass have a film interlayer to keep out infrared wavelengths while letting through visible light. Three Spheres ranging in size up to over 90 ft tall and 130 ft in diameter form a single indoor environment, with open airflow between them and radiant floor heating and cooling to keep the atmosphere between 60 and 85 percent humidity.

Among the waterfalls, epiphytic trees, and four-story living wall are treehouse meeting rooms and an open environment that does away with offices and conference rooms.

The Spheres will include a visitor center called the Understory that includes a fully immersive, 360-degree experience about the science, engineering, and plants behind the Spheres.

"Our goal with the Spheres was to create a unique gathering place where employees could collaborate and innovate together, and where the Seattle community could gather to experience biodiversity in the center of the city," says John Schoettler, Amazon Vice President of Global Real Estate and Facilities. "I am very proud and thankful to the entire team who made the Spheres a reality – they did a terrific job from the design all the way to the finishing touches. We are thrilled to officially open the doors."

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