“Asaro from the Eastern Highlands”. The mudmen could not cover their faces with mud because the people of Papua New Guinea thought that the mud from the Asaro river was poisonous. So instead of covering their faces with this alleged poison, they made masks from pebbles that they heated and water from the waterfall, with unusual designs such as long or very short ears either going down to the chin or sticking up at the top, long joined eyebrows attached to the top of the ears, horns and sideways mouths. (Photo and caption by Jimmy Nelson)

Brazilian natives of the Pareci tribe play head football with a hand-made ball for a demonstration, during the first day of the International Games of Indigenous Peoples, in Cuiaba, state of Mato Grosso, on November 10, 2013. 1500 natives from 49 Brazilian ethnic groups and from another 17 countries are gathering in Cuiaba until November 16 to compete in some 30 athletic disciplines, many of their own. (Photo by Christophe Simon/AFP Photo)

A person drags a suitcase as a boy clings to it on a square in front of a railway station ahead of the Chinese Lunar New Year in Qingdao, Shandong province, January 28, 2014. About 3.62 billion trips will be made during the 40-day Spring Festival travel rush, which started from January 16, reported Xinhua News Agency citing a government official. (Photo by Reuters/China Daily)

A picture made available on 20 June 2016 shows people praying as they wait to break the fast during the Muslim holy month of Ramadan, in Karachi, Pakistan, 19 June 2016. Muslims around the world celebrate the holy month of Ramadan by praying during the night time and abstaining from eating and drinking during the period between sunrise and sunset. Ramadan is the ninth month in the Islamic calendar and it is believed that the Koran's first verse was revealed during its last 10 nights. (Photo by Shahzaib Akber/EPA)

This April 30, 2016 image made available by NOAA shows a deep sea anglerfish living between pillow basalt rock formations, during a deepwater exploration of the Marianas Trench Marine National Monument area in the Pacific Ocean near Guam and Saipan. The ambush predator waits for prey to be attracted by its lure, located between its eyes, and gulps it with its large mouth. (Photo by NOAA Office of Ocean Exploration and Research via AP Photo)

Sergei Bobkov, 59, paints Siberian cedar nut oil onto a life-size sculpture of Pallas's Cat, also known in Russia as Manul Cat, which he made from Siberian cedar wood shavings using more than 700 thousand pieces over four years, in the village of Kozhany, southwest of the Siberian city of Krasnoyarsk, Russia, April 28, 2017. (Photo by Ilya Naymushin/Reuters)

Rougine, a 19-year-old female Arab fighter among the Syrian Democratic Forces, made up of US-backed Kurdish and Arab fighters, stands in fatigues embracing another colleague near the village of al-Torshan, 20 km on the outskirts of Raqa on February 6, 2017. (Photo by Delil Souleiman/AFP Photo)

Adrienne Sipe (L) and Brooke Gilliam of Washington D.C. leap off a snow podium they made near the U.S. Capitol in Washington February 13, 2014. A deadly and intensifying winter storm packing heavy snow, sleet and rain pelted a huge swath of the U.S. East Coast on Thursday, grounding flights and shuttering schools and government offices. (Photo by Kevin Lamarque/Reuters)