Merfolk gather at MerMania 2017, the world's largest gathering of amateur and professional mermaids and mermen in North Carloina, USA on January 21, 2017. (Photo by Brian Cahn/ZUMA Wire/Rex Features/Shutterstock)

The world-famous sprinter Usain Bolt, 30, took a break from the track to celebrate Carnival as revellers doused each other with paint in Trinidad and Tobago on February 26, 2017. (Photo by David Wears/Splash News and Pictures)

A dancer of Potosi's government departament, poses with traditional costumes at the Salar de Uyuni, the world's largest salt flat, in Uyuni, Bolivia, on November 7, 2020. (Photo by Ronaldo Schemidt/AFP Photo)

Neutral athletes Mayya Doroshko and Tatiana Gayday compete in the women's duet technical preliminary of artistic swimming at the World Aquatics Championships in Singapore, Friday, July 18, 2025. (Photo by Vincent Thian/AP Photo)

An athlete takes part in a warm-up around the track of the National Stadium in Tokyo on September 12, 2025, ahead of the World Athletics Championships. (Photo by Kirill Kudryavtsev/AFP Photo)

An iguana rests on a man's head during a pet blessing ceremony a day after World Animal Day, at a mall in Quezon City, Metro Manila, Philippines on October 5, 2025. (Photo by Noel Celis/Reuters)

“Centuries ago, Inuit hunted the bowhead whale. At that time, whale hunting undoubtedly was part of a complex and very important ritual, if only because of the size of the catch. The position that the ancestors of today's Inuit occupied in the living world involved a relationship with the spirit that inhabited each animal but also their species”. (Photo by Robert Frechette/2014 Sony World Photography Awards)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)