A man watches a wave hit a rock pool at Curl Curl beach as large swell hits the East Coast of Australia on June 6, 2016 in Sydney, Australia. Torrential rain over the weekend saw streets and homes flooded while wind gusts up to 120km per hour brought down trees and powerlines. A king tide has also seen beachside homes evacuated on Sydney's northern beaches as large waves erode the coast. (Photo by Cameron Spencer/Getty Images)

While many of us would pay good money for a spa mud bath, these fortunate hippos in South Luangwa National Park, Zambia, have nature to thank as they take a plunge in a lagoon in the second decade of February 2024. (Photo by Dimitar Nedelchev/Solent News)

China's Zheng Si Wei, right, and Huang ya Qiong play against Thailand's R. Makkasasithorn and J. Sudjaipraparat during their mixed doubles match at the Badminton Asia Championships 2022 at Muntinlupa, Philippines on Tuesday, April 26, 2022. (Photo by Aaron Favila/AP Photo)

Cosplayer Barbie Chula poses for a photo on the last day of the New York Comic Con 2021 at the Jacob Javits Center on October 10, 2021. The four-day event is the largest pop culture event on the East Coast. (Photo by Timothy A. Clary/AFP Photo)

NHRA top fuel driver Spencer Massey explodes the engine of his dragster on fire during the Thunder Valley Nationals at Bristol Dragway on October 17, 2021. Massey was unhurt in the incident. (Photo by Mark J. Rebilas/USA TODAY Sports)

Colombia's Harold Tejada climb Plateau des Glieres during the stage 18 of the Tour de France cycling race over 175 kilometers (108.7 miles) from Meribel to La Roche-sur-Foron, France, Thursday, September 17, 2020. (Photo by Thibault Camus/AP Photo)

A Monster Jam truck performs a back flip during the first-ever monster truck event in Beijing's iconic “Bird's Nest” National Stadium on Saturday, July 29, 2017. (Photo by Ng Han Guan/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)