A competitor reacts ahead of Tough Guy Mudathon event in Perton, Britain, 04 February 2018. The original event which started in 1987 raises money for charity and challenges thousands of international competitors with a cross-country run followed by an assault course consisting of 20 obstacles including water, fire and tunnels. (Photo by Nigel Roddis/EPA/EFE)

Models pose alongside the Kia SP SUV Concept car after its launch at India Auto Show 2018 in Greater Noida, February 7, 2018. The biennial automobile exhibition opens to public Friday and runs till Feb. 14. (Photo by Saumya Khandelwal/Reuters)

Models present creations from the Versace Autumn/Winter 2018 women collection during Milan Fashion Week in Milan, Italy February 23, 2018. (Photo by Alessandro Garofalo/Reuters)

A visitor tries out Lenovo augmented reality glasses with the Star Wars Jedi Challenges during the Mobile World Congress in Barcelona, Spain, February 26, 2018. The Mobile World Congress, the world' s biggest mobile fair, is held in Barcelona from February 26 to March 1. (Photo by Yves Herman/Reuters)

Liz Katz attends Day 1 of WonderCon held at Anaheim Convention Center on March 23, 2018 in Anaheim, California. (Photo by Albert L. Ortega/Getty Images)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

An ice hockey-themed crew in the 2018 Zaplyv festival of handmade inflatables in 300 Years of St Petersburg Park in St Petersburg, Russia on August 5, 2018. (Photo by Peter Kovalev/TASS)

Best portfolio winner. Roseate Spoonbill, Platalea ajaja, by Petr Bambousek, Czech Republic. (Photo by Petr Bambousek/2018 Bird Photographer of the Year)