Central Palo Seco power station of the Puerto Rico Electric Power Authority (PREPA) is seen behind a cemetery, in San Juan, Puerto Rico on January 22, 2018. (Photo by Alvin Baez/Reuters)

An art wall painting representing performance artist Marina Abramovic by Italian artist Maurizio Cattellan to publicize his upcoming exhibition The Artist is Present, in Shanghai, China, is displayed on a facade of a building, in Milan, Italy, Wednesday, September 19, 2018. (Photo by Luca Bruno/AP Photo)

Olena Korzeniuk, a 15-year-old girl poses on the stairs during a bid to set the national record for the longest hair on a child in Kiev, Ukraine on March 12, 2019. During a ceremony, the experts of the National Register of Records found the blonde hair of the Ukrainian Rapunzel to be 2.35m (6.5ft) long. (Photo by Tarasov/Ukrinform/Barcroft Images)

Two men push a classic Messerschmidt KR200 “Kabinenroller” at the 7th Cairo Classic Meet in Cairo, Egypt, 23 March 2019. The exhibition for classic cars is held at the Smart Village in Cairo. The exhibition is held to exchange experiences in how to preserve the old cars, and also for promoting tourism. (Photo by Mohamed Hossam/EPA/EFE)

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)

Eva Longoria Farmer Visits "The Tonight Show Starring Jimmy Fallon" at Rockefeller Center on November 24, 2015 in New York City. (Photo by Theo Wargo/NBC/Getty Images for "The Tonight Show Starring Jimmy Fallon")

Eight-year-old Lactatia a.k.a. Nemis Quinn Mélançon Golden gets a makeover by Ginger Minj during RuPaul's DragCon NYC 2017 at The Jacob K. Javits Convention Center on September 9, 2017 in New York City. (Photo by Santiago Felipe/Getty Images)

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)