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 mahout guards the elephants during the annual Vrischikolsavam festival, which features a colourful procession of decorated elephants along with drum concerts, at a temple in Kochi, India, November 18, 2017. (Photo by Sivaram V/Reuters)

Filipino children play as they are doing caroling activities on the street near an airport, days before Christmas in Manila, Philippines, 20 December 2017. Filipinos celebrate the longest Christmas in the world which starts as early as September every year. (Photo by Francis R. Malasig/EPA/EFE)

A boy plays with pelicans in Yoff, commune of Dakar, Senegal March 14, 2018. (Photo by Zohra Bensemra/Reuters)

An artwork called “Beyond Crisis” by French artist Guillaume Legros aka Saype and created with an eco paint made out of chalk and coal over a 3000 sqm field is pictured during the coronavirus disease (COVID-19) outbreak in Leysin, Switzerland, April 24, 2020 in this picture obtained by Reuters April 26, 2020. (Photo by Valentin Flauraud/SAYPE/Handout via Reuters)

Sеx worker Moira Mona wears a mask at her studio where she creates videos near Amsterdam, Netherlands on June 30, 2020. (Photo by Piroschka van de Wouw/Reuters)

Firefighters are seen through heat from flames as they battle the Apple fire near Banning, California on August 1, 2020. 4,125 acres have burn in Cherry Valley, about 2,000 people have received evacuation orders in the afternoon of August 1. Around 8PM the fire spread to 12,000 acres. (Photo by Josh Edelson/AFP Photo)

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)