In this August 24, 2019 photo, a tractor pulls a trailer that was converted into a swimming pool as it drives along the roads of El Infernal neighborhood in San Andres in the province of Pinar del Río, Cuba. The idea for the mobile tractor-pool was hatched by local parents, to make their kids happy and fight the harsh Caribbean heat. (Photo by Ramon Espinosa/AP Photo)

“The finless porpoise (Neophocaena phocaenoides) is one of six porpoise species. In the waters around Japan, at the northern end of its range, it is known as the sunameri. A freshwater population found in the Yangtze River in China is known locally as the jiangzhu or «river pig»”. – Wikipedia

Photo: A newly born Yangtze finless porpoise (top) swims with his mother at the Hydrobiology Institute of the Chinese Academy of Sciences on June 3, 2007 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

“Yokohama Hakkeijima Sea Paradise is an amusement park consisting of an aquarium, shopping mall, hotel, marina and amusement rides. It is located in Kanazawa-ku, Yokohama, Japan. It opened for business on May 8, 1993”. – Wikipedia

Photo: Shoal of sardines and sharks swim in a tank at Yokohama Hakkeijima Sea Paradise on March 19, 2009 in Yokohama, Japan. (Photo by Junko Kimura/Getty Images)

Members of Team Japan compete in the Artistic Swimming Team Acrobatic Final on day four of the Fukuoka 2023 World Aquatics Championships at Marine Messe Fukuoka Hall A on July 17, 2023 in Fukuoka, Japan. (Photo by Quinn Rooney/Getty Images)

South Korea's Hur Yoonseo and Lee Riyoung take part in the Free Routine segment of the Artistic Swimming Women's Duet competition at the 19th Asian Games in Hangzhou, China, Saturday, October 7, 2023. (Photo by Ng Han Guan/AP Photo)

Trainers from Tianjiao Special Guard/Security Consultant Ltd. Co. engage trainees dressed in swimming suits as they crawl on the beach during a training session in Sanya, Hainan province January 8, 2012. (Photo by CHINA DAILY/Reuters)

This undated handout picture taken by Tim Samuel and provided through his Instagram account shows a small fish swimming inside the belly of a jellyfish off the coast of Byron Bay in New South Wales, eastern Australia. A fish has been pictured swimming inside a jellyfish off Australia's east coast in a remarkable and rare image that has gone viral, with more than two million online views. Underwater photographer Tim Samuel was in the water with a friend near popular tourist resort Byron Bay in December when they came across the little creature trapped inside the only slightly larger jellyfish. (Photo by Tim Samuel Photography/AFP Photo/Instagram)

A girl jumps over a campfire while celebrating Ivan Kupala Night, a traditional Slavic holiday not far from Kiev on July 6, 2013. During the celebration, originating in pagan times, people plait wreaths, jump over fires, and swim naked. (Photo by Sergei Supinsky/AFP Photo)