An aerial view shows a sinkhole 3.5 km (2 miles) to the east of Solikamsk-2 mine in Perm region, November 20, 2014. Shares in Russia's Uralkali, the world's top potash producer, fell sharply for a second day on Wednesday after a mine accident that could reduce global supplies and push up prices of the crop nutrient worldwide. Uralkali shares have fallen 28 percent since Tuesday when it suspended work at its Solikamsk-2 mine, which accounts for a fifth of the company's output and 3.5 percent of global capacity, following an inflow of water. A sinkhole, stretching 30 by 40 metres (yards), found at an abandoned mine 3.5 km (2 miles) to the east, increased concern about the future of the mine because an inflow of water and the resulting sinkhole in 2006 forced another Uralkali operation to shut permanently. (Photo by Reuters/Press service of Uralkali company)

Antonina Yermokhina, 86, does physical exercises during her daily training session on the embankment of the Yenisei River in the Siberian town of Divnogorsk, Russia November 13, 2017. (Photo by Ilya Naymushin/Reuters)

American model Angela Renee White, professionally known as Blac Chyna arrives in a sheer black dress at Project LA Nightclub in Los Angeles, CA on August 16, 2018. (Photo by Headlinephoto/Splash News and Pictures)

Female winner Ane Guro Moen at Hardangervidda Marathon on September 2, 2017 in Eidfjord, Norway. Hardangervidda Marathon goes through parts of the National Park of Hardangervidda, passing through glaciers and waterfalls. (Photo by Kai-Otto Melau/Getty Images)

An undated handout picture released on January 10, 2017 by the Issekinicho publishing house shows an inter- species sexual behaviour between a male Japanese macaque and female sika deer, in Yakushima Scientists revealed on January 10, 2017 the “highly unusual” behaviour of a male monkey filmed trying to have sеx with female deer in Japan – a rare case of inter- species nookie. (Photo by Editions Issekinicho/AFP Photo)

A masked Burundian protester faces soldiers in front of a burning barricade during an anti-government demonstration against President Pierre Nkurunziza's bid for a third term in the capital Bujumbura, Burundi, 25 May 2015. Street protests continued on 25 May as the United Nations Secretary-General Ban Ki-moon condemned the killing of the leader of the oppsition party Union for Peace and Development (UPD) Zedi Feruzi who opposed Nkurunziza's bid. (Photo by Dai Kurokawa/EPA)

A camel herder removes the rope from the mouth of a camel at the Pushkar Fair in Rajasthan, India, November 22, 2015. Thousands of animals, mainly camels, are brought to the annual fair to be traded. (Photo by Jitendra Prakash/Reuters)

“Thor Heyerdahl (October 6, 1914, Larvik, Norway – April 18, 2002, Colla Micheri, Italy) was a Norwegian ethnographer and adventurer with a background in zoology and geography. He became notable for his Kon-Tiki expedition, in which he sailed 8,000 km (4,300 miles) by raft from South America to the Tuamotu Islands. All his expeditions are shown in the Kon-Tiki Museum, Oslo”. – Wikipedia

Photo: Norwegian anthropologist Thor Heyerdahl with a model of the balsa raft “Kon-Tiki” on which he drifted 4,300 miles from Peru to the Tuamotu Islands, proving his theory that Polynesia could originally have been populated by South Americans. (Photo by Express/Express/Getty Images). 1950