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)

A street entertainer waits for tourists in Havana, Cuba on October 2009. (Photo by Desmond Boylan/Reuters)

Award-winning photographer Barry Lewis has been picturing the weird and wonderful late-night Glastonbury experience for more than a decade. Shangri-La is a festival of contemporary performing arts held each year at Glastonbury festival, and Barry Lewis has documented its denizens. Here: Spa in Slumbarave’s Hotel Metropolis, Shangri-La, Glastonbury, 2009. (Photo by Barry Lewis/The Guardian)

Starting on Monday, August 12, Perseid meteors will streak across the summer sky for a couple of nights, offering casual stargazers and serious nighttime photographers a chance to capture a glimpse of the annual meteor shower. Photo: Photographer David Kingham created this composite image from 23 photos on August 12, 2012. (Photo by David Kingham)

Katjinga, a Rhodesian ridgeback dog who lives on a 20-acre farm in Germany, adopted an abandoned pot-bellied piglet in August 2009. The tiny black piglet, named Paulinchen, had been so small at birth that her mother likely overlooked it. Katjinga's owner, Roland Adam, found the piglet alone and cold and brought it to his 8-year-old dog. (Photo by Fame Pictures)

A boy tumbles as he plays soccer on the streets of the Khayelitsha township in Cape Town, December 3, 2009. (Photo by Kai Pfaffenbach/Reuters)

Contorsionist Rich Miteku performs during the opening of the 41st Monte-Carlo International Circus Festival in Monaco on January 19, 2017. (Photo by Valery Hache/AFP Photo)

A view of the Sheikh Zayed highway in Dubai and some high rise buildings, November 8, 2007. (Photo by Steve Crisp/Reuters)