A model walks down the runway during the Fashion Palette Miami Australian Swim Show during Miami Swim Week, Sunday, July 15, 2018, in Miami Beach, Fla. (Photo by Lynne Sladky/AP Photo)

Bollywood actress Sushmita Sen walks the ramp to showcase the creation of designer Sunita Shanker during Lakme fashion week winter 2018 in Mumbai, India, Thursday, August 23, 2018. (Photo by Rajanish Kakade/AP Photo)

Bollywood actress and former p*rn star Sunny Leone stands with her wax likeness during its unveiling at the Madame Tussauds museum in New Delhi, India, Tuesday, September 18, 2018. The statue unveiled Tuesday represents the 37-year-old celebrity's acceptance by mainstream Indian society even as conservative Indian politicians condemn her p*rn-star past. (Photo by Anupam Nath/AP Photo)

U.S. first lady Melania Trump steps out of her motorcade vehicle as she departs Washington for a tour of several African countries from Joint Base Andrews, Maryland, U.S., October 1, 2018. (Photo by Carlo Allegri/Reuters)

Members of the China Disabled Peoples Performing Art Troupe perform “My Dream” at Jorge Eliecer Gaitan Theater in Bogota on August 30, 2017. China Disabled People's Performing Art Troupe Company composed of artists with some hearing, mental, motor, visual or speech disabilities, was founded in 1987 and is currently Honorary and Goodwill Ambassadors of Unesco for its great example of inclusion. (Photo by John Vizcaino/AFP Photo)

The “Rabid Transit” Burning Man art car erupts with flames from it's onboard propane poofers during the 4th day of the annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S., August 31, 2017. (Photo by Jim Bourg/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")

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)