In this October 15, 2014 file photo, Katsu Nakamura, sky division manager for Yamaha USA, moves the RMax unmanned helicopter into position before a demonstration of its aerial application capabilities at the University of California, Davis' Oakville Station test vineyard in Oakville, Calif. Researchers at UC Davis have been studying the effectiveness of the drone's ability for spraying pest control and nutritional materials on the test vineyard in California's Napa Valley. (Photo by Rich Pedroncelli/AP Photo)

Snow covers roofs, streets and the Charles River following a winter blizzard in Boston, Massachusetts January 28, 2015. A powerful blizzard struck Boston and surrounding New England on Tuesday, leaving some 4.5 million people grappling with as much as three feet of snow and coastal flooding. (Photo by Brian Snyder/Reuters)

Visitors photograph an animatronic Tyrannosaurus Rex at the National Museum of Scotland, July 29, 2011. (Photo by David Moir/Reuters)

In this Wednesday, June 8, 2016 photo, Joe Giles, an actor portraying a zombie in “The Walking Dead”, poses with social media reporter Danielle Datu during a walker boot camp at Universal Studios Hollywood in Los Angeles. (Photo by Jae C. Hong/AP Photo)

Ostriches wear masks as they are transported by a truck for relocation in Zhengzhou, Henan Province, China, August 8, 2016. (Photo by Reuters/Stringer)

Residents ride on top of an overcrowded “Jeepney”, a locally manufactured public transport, along a highway in Mogpog town on Marinduque island in central Philippines April 8, 2015. (Photo by Erik De Castro/Reuters)

David Guttenfelder was born in Iowa and graduated from the University of Iowa with a Bachelor of Arts in cultural anthropology. He has worked for the AP since 1994 based in Kenya, the Ivory Coast, India and Japan. He is currently AP’s chief Asia photographer and his feature work has been used prominently in editorial publications throughout the world including Time and National Geographic. Photo: U.S. soldiers from the 2nd Battalion, 12th Infantry Regiment, 4th Brigade Combat Team, fire mortars at known enemy firing positions from a base in the Pech River Valley in Afghanistan's Kunar province, Saturday, October 24, 2009. (Photo by David Guttenfelder/AP Photo)

A Uyghur boy sits atop a horse as he has his picture taken outside the Id Kah Mosque before the Eid holiday on July 28, 2014 in old Kashgar, Xinjiang Province, China. Nearly 100 people have been killed in unrest in the restive Xinjiang Province in the last week in what authorities say is terrorism but advocacy groups claim is a result of a government crackdown to silence opposition to its policies. China's Muslim Uyghur ethnic group faces cultural and religious restrictions by the Chinese government. Beijing says it is investing heavily in the Xinjiang region but Uyghurs are increasingly dissatisfied with the influx of Han Chinese and uneven economic development. (Photo by Kevin Frayer/Getty Images)