Dancer Chachi Gonzalez arrives at Nickelodeon's 2016 Kids' Choice Awards in Inglewood, California March 12, 2016. (Photo by Mario Anzuoni/Reuters)

Teenagers on roller skates hold on to each other as they are pulled by a vintage car to move along a street in Havana, Cuba March 19, 2016. (Photo by Ivan Alvarado/Reuters)

Women perform under black fabric during a street performance in Pristina on October 6, 2017 against sexual harassments in Kosovo. (Photo by Armend Nimani/AFP Photo)

Hospitality staff are reflected in a puddle of water as they prepare to pose for photograph in front of a giant basket decorated with replicas of flowers and fruits on display on Tiananmen Square during the opening ceremony of the 19th Party Congress in Beijing, Wednesday, October 18, 2017. Chinese President Xi Jinping on Wednesday urged a reinvigorated Communist Party to take on a more forceful role in society and economic development to better address “grim” challenges facing the country as he opened a twice-a-decade national congress. (Photo by Andy Wong/AP Photo)

A racegoer is given some water as he lays on the ground following 2017 Stakes Day at Flemington Racecourse on November 11, 2017 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

A girl smiles as her hair is blown by a strong wind in the Chinatown area in Yokohama, near Tokyo, Friday, January 27, 2017. (Photo by Koji Sasahara/AP Photo)

This picture taken on February 16, 2017 in Fangshan village in China's coastal province Fujians, shows a villager performing the “eating flowers” ritual. Villagers in eastern China have a unique way of washing away the taint of evil spirits – by bathing in a shower of scorching sparks. (Photo by Johannes Eisele/AFP Photo)

Brain-on-a-chip. Dazzling in green and magenta this image shows the nerve fibres (in green) produced by neural stem cells (in magenta) as they grow on a synthetic gel. Captured by a technique known as confocal microscopy, the image is part of research shedding light on how tinkering with the environment can affect the way in which nerve fibres grow. (Photo by Collin Edington and Iris Lee/Massachusetts Institute of Technology/Wellcome Images)