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)

This photo taken on February 26, 2019 shows an aerial view of a tea field in Zhangping in China's eastern Fujian province. (Photo by AFP Photo/China Stringer Network)

Ana Mendez Casteñeda smokes marijuana during “Fumaton 420” outside the national Senate in Mexico City, Tuesday, April 20, 2021. The demonstrators are calling for the legalization of marijuana. (Photo by Marco Ugarte/AP Photo)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)

Breath at sunset, captures a sea turtle at a dive site called Black Rock. Kāʻanapali, Hawaiʻi, August 2013. (Photo by Christopher Doherty/Smithsonian.com)

Partygoers dance the night away on July 19, 2021 at Astoria Nightclub in Portsmouth, Hampshire, United Kingdom which opened its doors at 12:01am on Monday. (Photo by Paul Jacobs/Picture Exclusive)

A group of people walk on the sea wall as a man kayaks through the flooded parking lot in downtown Annapolis, Maryland, on October 29, 2021. The US National Weather Service implemented a flood watch for the cities of Baltimore and Annapolis as well as Anne Arundel, Baltimore and Howard counties. Washington, DC, and parts of Virginia faced the same alert. (Photo by Jim Watson/AFP Photo)

A woman reacts during the annual tomato fight fiesta called “Tomatina”, tomato fight fiesta, in the village of Bunol near Valencia, Spain, Wednesday, August 30, 2023. Thousands gather in this eastern Spanish town for the annual street tomato battle that leaves the streets and participants drenched in red pulp from 120,000 kilos of tomatoes. (Photo by Alberto Saiz/AP Photo)