Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

Women dancing at the disco club Xenon in New York City, USA in 1978. Xenon was a popular disco in Manhattan in the late 1970s and early 1980s. It was the only nightclub popular enough to compete with Studio 54. (Photo by Waring Abbott/Getty Images)

Pals let their hair down for one last hoorah in Cardiff, capital of Wales on September 12, 2020. Groups of friends crammed into pubs and restaurants to “go out in style” before the “rule of six” is enforced on Monday. (Photo by Huw Evans Picture Agency/The Sun)

An Asian elephant cools off at the zoo during the World Elephant Day in Lodz, central Poland, 12 August 2022. The World Elephant Day is observed every year on August 12. (Photo by Grzegorz Michalowski/EPA/EFE/Rex Features/Shutterstock)

A model wears a creation for the Thom Browne ready-to-wear Spring/Summer 2023 fashion collection presented Monday, October 3, 2022 in Paris. (Photo by Vianney Le Caer/Invision/AP Photo)

Men try to get control of a bucking horse a Tradition Day rodeo exhibition during, in San Antonio de Areco, Argentina, Sunday, November 13, 2022. Tradition Day, aimed to preserve gaucho traditions, is celebrated to honor the birth of Argentine writer Jose Hernandez, author of the country's national poem, “The Gaucho Martin Fierro”. (Photo by Natacha Pisarenko/AP Photo)

Gold medalist Mujinga Kambundji, of Switzerland, left, and silver medalist Ewa Swoboda, of Poland, celebrate after finishing the Women 60 meters final at the European Athletics Indoor Championships at Atakoy Arena in Istanbul, Turkey, Friday, March 3, 2023. (Photo by AP Photo/Stringer)

Rows of workers shelter under umbrellas from the scorching heat as they painstakingly sort through a red carpet of millions of chilli peppers in Bogra, Bangladesh on October 3, 2023. They sort the rotten and broken chilli peppers out to separate the poor quality ones which won't sell. In a line, the pickers who are paid less than £3 for a 10-hour shift slowly move forward with their baskets to separate the bad from the good after the chilies have been dried in the sun for a week. (Photo by Joy Saha/Rex Features/Shutterstock)