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)

A woman refreshes at a fountain in Casa de Campo during a heatwave in Madrid, Spain on June 15, 2022. (Photo by Isabel Infantes/Reuters)

Canada's Suzanna Shahbazian competes with the ball in the individual all-around rhythmic gymnastics final at the Arena Birmingham, on day eight of the Commonwealth Games in Birmingham, central England, on August 5, 2022. (Photo by Jason Cairnduff/Reuters)

Japan's Mei Tsuruta competes in the rhythmic gymnastics individual qualification and individual team final event during the Hangzhou 2022 Asian Games in Hangzhou, in China's eastern Zhejiang province on October 6, 2023. (Photo by Philip Fong/AFP Photo)

Revellers took to the bars and clubs of Birmingham, UK on Thursday night, April 6, 2023, knowing that they didn't have to go to work on Good Friday. (Photo by Roland Leon/News Group Newspapers Ltd)

During Madrid's pride week, participants compete during the annual high heel race in Madrid, Spain, Thursday, July 29, 2023. Competitors must wear shoes with a heel of a minimum of 15 centimetres (5.9 inches). (Photo by Bernat Armangue/AP Photo)

A sculptural artwork creation is displayed as part of the “Fashion in Motion: Daniel Lismore” exhibition by British multidisciplinary artist Daniel Lismore, at the Victoria and Albert Museum in London, Britain on August 5, 2022. (Photo by Toby Melville/Reuters)

A Siberian tiger at a photographer for getting too much in its face during the presentation of two new Siberian tigers at Cabarceno Natural Reserve in Cabarceno, northern Spain, 21 July 2014. (Photo by Pedro Puente Hoyos/EPA)