Cambodia's Kun Sreynich and Philippines' Lopez Leah in action during individual judo finals at Chroy Changvar Convention Centre Hall C in Phnom Penh, Cambodia on May 15, 2023. (Photo by Kim Kyung-Hoon/Reuters)

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 baby dives as his mother holds on tightly during a water baby class in Odessa, Ukraine on August 6, 2016. (Photo by Andrey Nekrasov/Barcroft Images)

Students of Kiev's Olympic College perform during a rally in front of the Parliament building in Kiev, Ukraine, 15 September 2020. Students were protesting against the reorganization of the college, at risk of being closed, and the land where it rises which could end up for sale along with the facility's stadium. (Photo by Sergey Dolzhenko/EPA/EFE)

Girls sits on a bench during summer at the Central Park in New York, United States, 2011. (Photo by An Rong Xu)

Daniel Cheong, a dog behaviorist and trainer, steps over a leash as he walks a pack of dogs in Arlington, Va. on November 13, 2018. (Photo by Ricky Carioti/The Washington Post)

A woman stands in front of a mask-clad lion statue outside a department store in Tokyo's Ginza district on January 18, 2022, as Japan reported a record high of new Covid-19 infections fuelled by the Omicron variant. (Photo by Philip Fong/AFP Photo)

People look at the lava flowing on Fagradalsfjall volcano in Iceland on Wednesday August 3, 2022, which is located 32 kilometers (20 miles) southwest of the capital of Reykjavik and close to the international Keflavik Airport. Authorities in Iceland say the volcano in the southwest of the country is erupting just eight months after its last eruption officially ended. (Photo by Marco Di Marco/AP Photo)