A National Historic Landmark, the last remaining Japanese pagoda-style building that was one of the Zoo’s early bird aviaries, built in 1875, has been preserved as the Passenger Pigeon Memorial. The exhibit pays tribute to Martha, the last known passenger pigeon who died at the Zoo in 1914. Once the most numerous bird on Earth, the passenger pigeon was hunted into extinction. The exhibit serves as a reminder to all of the tragedy of extinction and pleas with visitors to consider how their actions affect wildlife. In commemoration of the centennial of the passenger pigeon’s extinction, the Passenger Pigeon Memorial underwent a renovation in 2014, transforming it from a single-species memorial to an educational exhibit with a positive and hopeful conservation message that segues from the story of the passenger pigeon to modern wildlife conservation efforts.