Tree trunks lie on the railtracks that will be used to transport nuclear waste on November 25, 2011 in Leitstade, near Metzingen, Germany. A train carrying the Castor containers of processed, spent nuclear fuel started from La Hague in France Wednesday for its journey to the Gorleben temporary nuclear waste storage facility in Germany, and thousands of protesters are expected to attempt to blockade the route. (Photo by Carsten Koall/Getty Images)

Emily Hasler, an English Heritage employee at Charles Darwin's home, Down House, cleans a rabbit bone in his old study on April 2, 2011 in Downe, England. Staff at the house are cleaning and preparing the property ahead of their peak visitor season. The house contains the study where Darwin wrote “On the Origin of Species”, as well as family rooms and an extensive garden that inspired the renowned scientist. (Photo by Oli Scarff/Getty Images)

A girl allows a butterfly to be placed on her nose at the Sensational Butterflies exhibition at the Natural History Museum on April 6, 2011 in London, England. The exhibition is divided up into five sensory zones exploring how butterflies see, hear, taste, smell and touch. The display containing hundreds of butterflies runs from April 12 to September 11, 2011. (Photo by Peter Macdiarmid/Getty Images)

Decorated eggs are seen at the egg museum in Winden am See, Austria, March 25, 2016. The collection of Austrian artist Wander Bertoni contains about 4000 eggs. (Photo by Christian Bruna/EPA)

An Afghan woman fills containers with water near her temporary shelter at an internally displaced person's (IDP) camp on the outskirts of Herat, Afghanistan, January 21, 2015. Dozens of families are living in temporary shelters even in harsh winters and most depend on aid distributions by the United Nations High Commissioner for Refugees (UNHCR). (Photo by Jalil Rezayee/EPA)

A policewoman wipes her tears as she stands in front of metal caskets containing the bodies of Special Action Force (SAF) police who were killed in Sunday's clash with Muslim rebels, at Villamor Air Base in Pasay city, metro Manila January 29, 2015. Philippine President Benigno Aquino urged legislators on Wednesday not to abandon a plan for autonomy for Muslims to end a decades-old insurgency after the clash in which dozens of people were killed, saying doing so would dash hopes for peace. (Photo by Romeo Ranoco/Reuters)

A makeshift cart with containers is seen at a suspected drug tunnel under construction during a media tour by Mexican Army in Tijuana April 7, 2015. Mexican soldiers foiled the construction of a suspected drug tunnel underneath a house near the U.S. border, arresting nine people and impounding a truck used to clear debris, the Army said on Tuesday. Wired with lights, the tunnel was being built next to the Tijuana border crossing, south of San Diego, California, and near a Mexican air force installation as well as a regional federal police facility. (Photo by Reuters/Stringer)

A resident looks into a newly-built giant trash can, partially buried underground, next to a street in Taiyuan, Shanxi province November 6, 2014. The trash can, which has a diameter of 1.9 meters and a depth of 2.8 meters, could contain approximately 10 cubic metres of garbage. It was built to replace an open-air garbage dump site, local media reported. (Photo by Reuters/Stringer)