Revelers perform during the Myths and Legends parade in Medellin, Antioquia department, Colombia on December 8, 2021. (Photo by Joaquin Sarmiento/AFP Photo)

An Iowa State Patrol trooper works the scene of an overturned semi truck along the westbound shoulder of Interstate 80 near Anita, Iowa, on Wednesday, December 15, 2021, after a band of intense weather crossed through the area. A powerful storm system is blowing through the Great Plains and Midwest, combining with unusually warm temperatures to close highways and prompt numerous tornado warnings. (Photo by Bryon Houlgrave/The Des Moines Register via AP Photo)

A child performs opera during celebrations on the eight day of Chinese Lunar New Year of the Pig, in Taizhou, Zhejiang province, China on February 12, 2019. (Photo by Reuters/China Stringer Network)

Villagers from Jiexi Jiantan village perform a ritual of “Zha Laoye”, or “Cracking local spirits”, in Chaoshan, Guangdong Province, China, 10 February 2019. Jiexi Jiantan Village celebrates the annual custom of “Zha Laoye” where Laoye are local spirits. Every third day of the lunar New Year, statues of local spirits known as the “Thousand-mile Eye” Laoye and “Ear Following the Wind” Laoye are brought out to the village committee to receive incensed tea offered by believers. (Photo by EPA/EFE/ZNSEN)

Ezra Miller attends the 2019 Met Gala celebrating “Camp: Notes on Fashion” at the Metropolitan Museum of Art on May 06, 2019 in New York City. (Photo by Andrew Kelly/Reuters)

Brazilian actress Julia Stockler (L) and Brazilian actress Carol Duarte kiss while posing with Brazilian film director Karim Ainouz during a photocall for the film “A Vida Invisivel de Euridice Gusmao (The Invisible Life of Euridice Gusmao)” at the 72nd edition of the Cannes Film Festival in Cannes, southern France, on May 20, 2019. (Photo by Stephane Mahe/Reuters)

In this photo taken on Sunday, March 10, 2019, a little girl laughs during a ritual marking the upcoming Clean Monday, the beginning of the Great Lent, 40 days ahead of Orthodox Easter, on the hills surrounding the village of Poplaca, in central Romania's Transylvania region. Romanian villagers burn piles of used tires then spin them in the Transylvanian hills in a ritual they believe will ward off evil spirits as they begin a period of 40 days of abstention, when Orthodox Christians cut out meat, fish, eggs, and dairy. (Photo by Vadim Ghirda/AP Photo)

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)