Girls prepare to take part in a mermaid lesson in Rio de Janeiro, Brazil May 28, 2017. Women in Brazil are not unique in their affinity for mermaiding. Classes are held as far away as Texas and some folks wonder if mermaiding will be the next fitness craze. (Photo by Pilar Olivares/Reuters)

Vernon Yates, founder of Wildlife Rescue and Rehabilitation, lays his hands on Ty, a 400-pound tiger, as staff prepare to surgically extract a 4-pound hairball from the big cat, in Clearwater, Florida, on May 22, 2013. Ty is cared for by Wildlife Rescue and Rehabilitation in Seminole. The non-profit animal rescue group mainly serves by assisting Florida law enforcement with animals that have been seized. (Photo by James Judge/Courtesy BluePearl Veterinary Partners)

Two boys look out from the Mangueira slum towards the Maracana Stadium that is hosting the Rio's 2016 Summer Olympics opening ceremonies, in Rio de Janeiro, Brazil, Friday, August 5, 2016. (Photo by Leo Correa/AP Photo)

Yakutsk, a remote city in Eastern Siberia along the Lena River, is the coldest city in the world. Located 1840 km away from Irkoustk and 5000 km away from Moscow, this city founded in 1632 by the Cossacks imposes upon its inhabitants an extreme way of life. And yet, despite particularly harsh conditions, Yakutsk boasts a population of 270,000, or a quarter of the entire population of Siberia. No other place on the planet experiences the temperature extreme found here: in winter, the temperatures regularly fall to minus 40° (the coldest temperature recorded was –64°C) and in summer often reaches temperatures above 30°C. Photo: January 2013. A scene in Yakutsk, Siberia, the coldest city in the world. (Photo by Steeve Iuncker/Agence VU)

Police officers display their AI-powered smart glasses in Luoyang, Henan province, China on April 4, 2018. (Photo by Reuters/China Stringer Network)

Blossoms and dust are blown by the wind as Jasmin Ricks, left, and her sister, Jessica Ricks, center, take in the cherry blossoms near the Tidal Basin in Washington on April 12, 2018. (Photo by Matt McClain/The Washington Post)

A man transports passengers on an improvised motorized rickshaw during heavy rains in Agartala, India, April 20, 2018. (Photo by Jayanta Dey/Reuters)

In this Thursday, June 14, 2018, file photo, students wear virtual reality goggles during a science class at Pyongyang Teachers' University, a teacher training college, in Pyongyang, North Korea. (Photo by Dita Alangkara/AP Photo)