Christian Bale poses for a fan at the 25th annual Screen Actors Guild Awards at the Shrine Auditorium & Expo Hall on Sunday, January 27, 2019, in Los Angeles. (Photo by Mario Anzuoni/Reuters)

Janelle Monae (L) and Taraji P. Henson pose with the SAG Award for Outstanding Cast in a Motion Picture award for “Hidden Figures”, during the 23rd annual Screen Actors Guild Awards ceremony at the Shrine Exposition Center in Los Angeles, California, USA, 29 January 2017. (Photo by Paul Buck/EPA)

Actress Laverne Cox attends The 59th GRAMMY Awards at STAPLES Center on February 12, 2017 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for NARAS)

Ciara attends the 2018 Vanity Fair Oscar Party following the 90th Academy Awards at The Wallis Annenberg Center for the Performing Arts in Beverly Hills, California, on March 4, 2018. (Photo by Jean-Baptiste Lacroix/AFP Photo)

Katie Austin (L) and Denise Austin attend the 2019 ESPY Awards at Microsoft Theater on July 10, 2019 in Los Angeles, California. (Photo by Chelsea Lauren/Rex Features/Shutterstock)

Jourdan Dunn poses for photographers upon arrival at the MTV European Music Awards 2016 in Rotterdam, Netherlands, Sunday, November 6, 2016. (Photo by NIVIERE/SIPA Press/Rex Features/Shutterstock)

Philippe Marquis of Canada during the FIS Freestyle Ski World Cup Dual Moguls on December 20, 2011 in Meribel, France. (Photo by Alain Grosclaude/Agence Zoom/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)