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)

Rick Sorenson, owner of the Rio Ramaza Marina, wades in the Sacramento River after securing an old paddlewheel boat on his property as the river makes its way up the levee on Garden Highway in Sacramento, Calif., Monday, January 9, 2017. (Photo by Hector Amezcua/The Sacramento Bee via 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)

A jogger runs on the bank of Donaukanal channel in central Vienna, Austria, September 5, 2016. (Photo by Heinz-Peter Bader/Reuters)

A Palestinian protester, dressed as Santa Claus, reacts after inhaling tear gas fired by Israeli troops during clashes in the West Bank city of Bethlehem December 23, 2016. (Photo by Mussa Qawasma/Reuters)

A protester in an Elmo mask dances during the Justice for George Floyd Philadelphia Protest on Saturday, May 30, 2020. Demonstrators took to the streets across the United States to protest the death of Floyd, a black man who was killed in police custody in Minneapolis on May 25. (Photo by Matt Rourke/AP Photo)

A woman looks on as she takes part in a protest on the Day of the Dead against gender violence and femicide, in Mexico City, Mexico, November 2, 2020. (Photo by Raquel Cunha/Reuters)