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)

An Oriental Garden Lizard sits on a tree in Gauhati, India, Tuesday, April 16, 2019. During the breeding season, the male lizard's head and throat turn a bright color. (Photo by Anupam Nath/AP Photo)

Two brown bears bathe in their enclosure at the Wildpark Poing in Poing, Germany, Wednesday, August 8, 2018. (Photo by Lino Mirgeler/Deutsche Presse-Agentur via AP Photo)

Men walk towards law enforcement with their hands up on August 24, 2020 in Kenosha, Wisconsin. A second night of civil unrest occurred after the shooting of Jacob Blake, 29, on August 23. Blake was shot multiple times in the back by Wisconsin police officers after attempting to enter into the drivers side of a vehicle. (Photo by Brandon Bell/Getty Images)

Buddy the dog peers from a vehicle before the start of a movie at a drive in cinema in Snagov, Romania, Monday, June 1, 2020. Romania further loosened the measures imposed during a nationwide lockdown in order to limit the spread of the COVID-19 infections, with museums, open air restaurants, cinemas and beaches opening for public on Monday. (Photo by Andreea Alexandru/AP Photo)

A Salvadoran clown is seen wearing colorful clothes and face make-up during the parade within the framework of the National Salvadoran Clown Day that is celebrated on the first Wednesday of every December by legislative decree in San Salvador, El Salvador on December 07, 2022. After the pandemic crisis, dozens of Salvadoran clowns took to the streets to celebrate their day, and invite families to respect the work of bringing smiles to children and adults in El Salvador. (Photo by Alex Pena/Anadolu Agency via Getty Images)

Escorts of city prince Stefan I on their way to the key transfer for carnival in Maastricht, Netherlands on February 18, 2023. City prince Stefan I symbolically gains power over the city for three days. (Photo by Hollandse Hoogte/Rex Features/Shutterstock)