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)

Villagers offer flowers to a wild tusker, laying dead in a field in Panbari villagein Panbari village on the outskirts of Gauhati, India, Thursday, November 2, 2017. According to a veterinarian the tusker died of food poisoning. Scarcity of food and illegal encroachment of forest areas have forced these wild elephant to move to populated areas for food. (Photo by Anupam Nath/AP Photo)

Pascal Craymer seen attending Pam Hogg at Freemason's Hall during LFW February 2018 on February 16, 2018 in London, England. (Photo by Goff Photos)

Members of the Mayossa folk dance group pour water on a young woman in Kiskunmajsa, Hungary on April 2, 2018. According to an old Hungarian tradition, celebrated for several hundred years, young men pour water on young women, who in exchange present their sprinklers with beautifully colored eggs on Easter Monday. (Photo by Sandor Ujvari/EPA/EFE/Rex Features/Shutterstock)

US President Donald J. Trump holds a roundtable meeting with Hispanic leaders in the cabinet room before signing an Executive Order in the Rose Garden of the White House in Washington, DC, USA, on 09 July 2020. (Photo by Samuel Corum/EPA/EFE/Pool)

Participants dance during the Water Gun Festival on July 07, 2019 in Seoul, South Korea. Thousands of people enjoyed the annual festival which is being held over the weekend during the scorching heat summer in Korea. (Photo by Chung Sung-Jun/Getty Images)

In this August 26, 2019 photo, children of the Nambikwara Sarare tribe climb trees as they play in their indigenous reserve in the southwestern Amazon, near Conquista D'Oeste, in the Brazilian state of Mato Grosso. About 98% of all Brazil’s indigenous lands lie within the Amazon. (Photo by Andre Penner/AP Photo)

A Flame Skimmer or Firecracker Skimmer dragonfly (Libellula saturata) rests on a small branch in Topanga, California, USA, 18 June 2018. The Flame Skimmer dragonfly is found in the Western United States near ponds and creeks. (Photo by Mike Nelson/EPA/EFE)