A child dressed as a Roman centurion poses during a parade to mark the anniversary of the foundation of Rome in 753 BC, on April 23, 2017 in Rome. (Photo by Alberto Pizzoli/AFP Photo)

An operator adjusts a film projector during a wedding party in Bogor, Indonesia, February 18, 2017. Indonesian entrepreneur Kamaluddin loves the gritty look of old 35-millimeter film so much that he spends most of his nights screening vintage movies at weddings and parties around Jakarta, the capital. (Photo by Reuters/Beawiharta)

Festive decorations and illumination lights for the upcoming New Year and Christmas season are unveiled in Minsk, Belarus on December 15 , 2019. (Photo by Vasily Fedosenko/Reuters)

This photo taken on November 4, 2019 shows people taking part in a fish catching competition in a paddy field in Leishan county in China's southwestern Guizhou province, to celebrate the new year festival Miao people. (Photo by AFP Photo/China Stringer Network)

A handout photo made available by the Roscosmos State Corporation for Space Activities shows the Soyuz-2.1b launch vehicle with the OneWeb communication satellites launching from the Baikonur Cosmodrome, Kazakhstan, 07 February 2020. Thirty-four satellites from OneWeb were successfully put into orbit on a single Soyuz rocket from Baikonur. (Photo by Roscosmos/EPA/EFE)

Carolaine Reis and her son Miguel Alves, residents of the Aglomerado da Serra favela, wear a protective mask against the spread of the new Coronavirus (COVID-19) made by the seamstresses of the Remexe Favelinha studio, in the Aglomerado da Serra favela, on April 13, 2020 in Belo Horizonte, Brazil. Facial masks follow the protocol and guidelines defined by the Ministry of Health. Around 6,000 masks have already been produced. The masks are being distributed to a part of the population and sold throughout the country, in the amount of 5 reais per unit. (Photo by Pedro Vilela/Getty Images)

Young Slovaks dressed in traditional costumes throw a bucket of water at a girl as part of Easter celebrations in the village of Trencianska Tepla, Slovakia, April 9, 2012. Slovakia's men splash women with water to symbolize youth, strength and beauty for the upcoming spring season. (Photo by Samuel Kubani/AFP)

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)