A woman poses as she has her picture taken amid 1600 panda bear sculptures in Berlin August 5, 2013. Marking the 50th anniversary of its existence, on Monday the German branch of the World Wide Fund for Nature (WWF) environmental conservation organisation placed 1600 panda bear sculptures on front of Berlin's main train station to draw attention to the plight of the endangered species that serves as the NGO's mascot. There are currently 1600 panda bears alive in the wild, the organisation said in a press release. (Photo by Thomas Peter/Reuters)

“Serengeti National Park encompasses 5,700 square miles of grassy plains and woodlands near the northern border of Tanzania, and is home to more than 3,500 lions grouped into a couple dozen prides. Photographer Nick Nichols and videographer Nathan Williamson made several extended trips to the Serengeti between July 2011 and January 2013, determined to break new visual ground in their coverage of the Serengeti Lions”. Photo: Cubs of the Simba East pride: too young to kill but old enough to crave meat. Adult females, and sometimes males, do the hunting. Zebras and wildebeests rank high as chosen prey in the rainy season. (Photo by Michael Nichols/National Geographic via The Atlantic)

Palestinians and Israelis enjoy the Mediterranean sea during the first day of the Eid al-Fitr holiday in Tel Aviv, Israel, Thursday, August 8, 2013. The three-day Eid al-Fitr holiday marks the end of the holy fasting month of Ramadan. One of the most important holidays in the Muslim world, Eid al-Fitr, is marked with prayers, family reunions and other festivities. (Photo by Oded Balilty/AP Photo)

A general view showing the shipwrecked cruise ship Costa Concordia in an upright position after the salvage operations in Giglio island, Italy, 17 September 2013. Salvage crews pulled off a major engineering feat when they straightened the listed Costa Concordia cruise ship from the rocks it had been wedged against for the past 20 months. The delicate operation took 19 hours and was completed at 4 am (0200 GMT). The vessel ran aground near the island of Giglio, in Tuscany, in an accident that made world-wide news. (Photo by Angelo Carconi/EPA)

In this October 14, 2013 photo, ecology professor Ricardo Freitas catches a broad-snouted caiman to examine, then release back into the water channel in the affluent Recreio dos Bandeirantes suburb of Rio de Janeiro, Brazil. Caimans are like tanks, a very old species with a remarkable capacity for renovation that allows them to survive under extreme conditions where others couldn't, said Freitas, who runs the Instituto Jacare, or the Caiman Institute, which aims to protect the reptiles. (Photo by Felipe Dana/AP Photo)

In this September 1, 2015 photo, street artists Jenaro de Rosenzweig, left, and Alejandro Revilla pose for a portrait behind a restaurant's window covered with a mural by artist Francisco Munoz, signed with his artist's name below, in the Roma Norte neighborhood of Mexico City. Rosenzweig and Revilla founded the “Street Art Chilango” cooperative in March 2013, which is filling neighborhoods with public art by local street artists. (Photo by Rebecca Blackwell/AP Photo)

“The Independence day”. While on storm chasing expeditions in the Tornado Alley in USA I have encountered many photogenic supercell storms. This photograph was taken while we were approaching the storm near Julesburg, Colorado on My 28th, 2013. The storm was tornado warned for more than one hour, but stayed an LP storm through all its cycles and never produced a tornado, just occasional brief funnels, large hail and some rain. Photo location: Julesburg, Colorado, USA. (Photo and caption by Marko Korošec/National Geographic Photo Contest)

Iranian mourners cover themselves with mud during Ashoura, marking the death anniversary of Imam Hussein, the grandson of Islam's Prophet Muhammad, at the city of Bijar, west of the capital Tehran, Iran, Thursday, November 14, 2013. Hussein, one of Shiite Islam's most beloved saints, was killed in a 7th century battle at Karbala, Iraq. (Photo by Ebrahim Noroozi/AP Photo)