Nature and urban life combine in Phoenix to create an ecosystem all its own

• Urban and suburban growth has exploded in the Valley of the Sun over the past five decades, creating a playground for the rich, an attractive oasis for families, and a brand new ecosystem for plants, animals and the humans who interact with it all.
• If ecosystem and city seem like oxymorons, just go deep inside this low-density metropolis and look at all the lakes and canals, the year-round greenery, the multitude of birds, or listen to the coyotes howling at night.
• A cutting-edge seven-year study by more than 50 scientists from different fields has concluded that the profusion of bugs, birds and bigger creatures roaming this one-time desert outpost represent a unique realm of nature.
• Like the rest of nature, this and other cities around the world are now being studied from an ecologist's point of view.
• "People in ecology are beginning to talk about designer ecosystems -- systems that have been heavily influenced by humans," says Arizona State University (ASU) professor Nancy Grimm, co-leader of new study.
• "It's not what people generally think -- they think there's either nature or there are cities," Redman said.
• The Valley of the Sun, as locals call the area, is crisscrossed with more canals than Percival Lowell thought he saw on Mars.
• Amid all this, several small mountains pop up, dotted by saguaros and preserved in their natural state.
• A person out in the natural desert or even in the distant suburbs of Phoenix would have to hire a mosquito to get bit, yet parts of the metro area last summer saw some of the highest concentrations of West Nile Virus anywhere in the country.
• Unlike many cities whose populations have shrunk or been flat in recent decades, Phoenix is a laboratory of expansion, making it a unique city for this sort of study.
• Last year, Phoenix proper took over fifth place from Philadelphia on the list of largest U.S. cites.