A woman dressed up for Halloween travels on a Metro train in São Paulo, Brazil on October 30, 2017. (Photo by Cris Faga/Rex Features/Shutterstock)

A Mongolian wrestler adjusts her hair before a match during the 2016 World Sumo Championship on July 30, 2016 in Ulaanbaatar, Mongolia. (Photo by Taylor Weidman/Getty Images)

A woman looks at a handgun at the Glock booth at the Shooting Hunting and Outdoor Trade Show, Tuesday, January 19, 2016, in Las Vegas. The SHOT Show, the world's largest annual trade show for shooting, hunting and law enforcement professionals, runs through January 23 and is expected to feature 1,600 exhibitors showing off their latest products and services to more than 62,000 attendees. (Photo by John Locher/AP Photo)

Fireworks and light effects illuminate the night sky from the Taipei 101 skyscraper during New Year's Eve celebrations in Taipei, Taiwan, 01 January 2019. (Photo by Ritchie B. Tongo/EPA/EFE/Rex Features/Shutterstock)

Determination: silver. Adam Pelech (No 3) of the New York Islanders and Brian Boyle of the Florida Panthers crash the boards during their game at Barclays Center in New York. (Photo by Al Bello/Getty Images)

Shortlist, open competition, lifestyle. Healing Vibes – the hot springs of Bagno Vignoni in Italy flow out at a temperature of about 49°C. They were appreciated by the Romans for their healing powers, and have been used as therapeutic treatments since the 12th century, under Emperor Federico II. (Photo by Stefano Butturini/Sony World Photography Awards)

Vehicles are burning as thousands of people take to the streets during the May Day demonstrations on May 1, 2018 in Paris, France. This month celebrates the 50th anniversary of May 68 when France seen millions of students and striking workers, come onto the streets in demonstrations that changed the country. (Photo by Jeff J. Mitchell/Getty Images)

In this handout image provided by Ogilvy, a burger made from cultured beef, which has been developed by Professor Mark Post of Maastricht University in the Netherlands (pictured) is shown to the media during a press conference on August 5, 2013 in London, England. The in-vitro burger, cultured from cattle stem cells, the first example of what its creator says could provide an answer to global food shortages and help combat climate change, was fried in a pan and tasted by two volunteers. The burger is the result of years of research by Dutch scientist Mark Post, a vascular biologist at the University of Maastricht, who is working to show how meat grown in petri dishes might one day be a true alternative to meat from livestock.The meat in the burger has been made by knitting together around 20,000 strands of protein that has been cultured from cattle stem cells in Post's lab. (Photo by David Parry)