Newly commissioned 2nd lieutenants throw their caps in the air as a team of F-16 Air Force Thunderbirds fly over the 2011 graduating class of the U.S. Air Force Academy on May 25, 2011 in Colorado Springs, Colorado. A total of 1,021 graduates received their diplomas in front of their families and dignitaries at the Academy's Falcon Stadium. (Photo by John Moore/Getty Images)

Students from John Moores' University celebrate and pose for family photographs as they take part in their degree congregations at Liverpool's Anglican Cathedral on July 13, 2011 in Liverpool, England. Thousands of students are taking part in graduations across Britain and will begin looking for employment. According to recent surveys there are currently 83 graduates chasing every job vacancy. (Photo by Christopher Furlong/Getty Images)

An altar is pictured after it was decorated by the Antar family with some 3,000 traditional cheese and corn buns called “chipas”, in celebration of Kurusu Ara in Asuncion May 3, 2015. Kurusu Ara, the Day of the Cross, is a Catholic festival that is combined with local Gurani culture and falls annually on May 3. Paraguayans typically celebrate the festival with chipas, used to decorate religious shrines and altars. The chipas are later distributed to attendees. The buns at the top are arranged to read, “March 3 live”. (Photo by Jorge Adorno/Reuters)

The New World porcupine, family Erethizontidae, 1280 Gram born at 11 April 2015 Inventory in Zoo. Counting trade Fairs Weighing the Zoo is at 7 May 2015 too the 108 Birthday Zoo Hagenbeck Hamburg, Germany. (Photo by Imago/ZUMA Wire)

Arnaq Egede walks to the potato field on her family's farm on July 31, 2013 in Qaqortoq, Greenland. The farm, the largest in Greenland, has seen an extended crop growing season due to climate change. (Photo by Joe Raedle/Getty Images)

Girls cry as they get separated from their family at the border line dividing Macedonia and Greece August 21, 2015. At least 1,000 migrants and refugees pressed against Macedonian police lines on the Greek-Macedonian border on Friday and at least 10 people appeared to faint in the crush. People could be heard screaming and medical workers raced to treat those who passed out or were hurt. The crush ensued after police let several hundred through into Macedonia, having kept them out since Thursday under an emergency decree. (Photo by Ognen Teofilovski/Reuters)

People pose for souvenir photos along peach blossom flowers at a field in Hanoi February 6, 2015. The peach blossom, believed to bring luck to families, is used to decorate homes during the Vietnamese “Tet” (Lunar New Year festival), which will take place from February 14 to February 24. (Photo by Reuters/Kham)

Tommy Lindsey holds an enormous maple leaf that he found in Mount Vernon, Wash., October 28, 2013. Lindsey was walking with his family when he picked up the leaf that is more than two feet from stem to tip and more than 21 inches wide. (Photo by Frank Varga/The Skagit Valley Herald)