Contractor Kiewit Building Group has been selected by the Denver Zoo from a field of five bidders to build the $50 million, 10-acre Asian Tropics exhibit. When complete, in 2011, the exhibit---which will house elephants, rhinos, and myriad other animals---will be the largest in the zoo's 113-year history, notes the Denver Business Journal. Kiewit, of Omaha, Nebraska, built the zoo's Bird Propagation Center in 2007. A groundbreaking ceremony featuring Mayor John Hickenlooper, zoo President/CEO Craig Piper, and others is scheduled for tomorrow. Many of the diverse animals that will be included in Asian Tropics are highly endangered, according to the zoo. Currently, the zoo is showing off Kai, a hyena, born on the grounds in August (via 9News).