1974: American boxer Muhammad Ali, formerly Cassius Clay, strikes an aggressive pose at a press conference on November 29, 1974. (Photo by Harry Dempster/Express/Getty Images); American actor Will Smith at the Royal Premiere of the film Ali in London on December 11, 2001. Smith starred as Muhammad Ali in the film. (Photo by Dave Hogan/Getty Images)

Singer Vlad Topalov and model Victoria Lopyreva wear creations by designer YanaStasia on day 5 of the Mercedes-Benz Fashion Week Russia Fall/Winter 2011/2012 at the Congress Hall on April 4, 2011 in Moscow, Russia. (Photo by Pascal Le Segretain/Getty Images)

A model walks the runway in the Maria Escote fashion show during the Mercedes-Benz Fashion Week Madrid Autumn/Winter 2012 at Ifema on February 4, 2012 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

Emily Hasler, an English Heritage employee at Charles Darwin's home, Down House, cleans a rabbit bone in his old study on April 2, 2011 in Downe, England. Staff at the house are cleaning and preparing the property ahead of their peak visitor season. The house contains the study where Darwin wrote “On the Origin of Species”, as well as family rooms and an extensive garden that inspired the renowned scientist. (Photo by Oli Scarff/Getty Images)

Actress Anna Valle attends the Roberto Cavalli Autumn/Winter 2012/2013 fashion show as part of Milan Womenswear Fashion Week on February 27, 2012 in Milan, Italy. (Photo by Vittorio Zunino Celotto/Getty Images)

Model Bianca Balti prepares backstage at the Iceberg Autumn/Winter 2012/2013 fashion show as part of Milan Womenswear Fashion Week on February 24, 2012 in Milan, Italy. (Photo by Tullio M. Puglia/Getty Images)

Dancers take part in “La Vijanera”, a winter masquerade at the beginning of carnival season in Europe, in Silio, northern Spain, January 8, 2017. (Photo by Vincent West/Reuters)

South African surfer Andy Marr rides a wave at Dungeons offshore reef in the Atlantic Ocean outside Cape Town, South Africa, 01 September 2016. The big wave surfing season is at its peak with winter swells driven by storms in the South Atlantic breaking on the Cape's outer reefs providing good conditions. Big wave surfers are competing in the 2016 Striped Horse Challenge and Rebel Sessions big wave competitons symultaneously throughout the season. (Photo by Nic Bothma/EPA)