Professional dog walker Jon Lovette of Jonny Walkers walks with dogs at Crissy Field on October 19, 2011 in San Francisco, California.

Cheerleaders wait to perform before the New Year's Day parade in London, Britain January 1, 2017. (Photo by Neil Hall/Reuters)

Wrestlers perform at an all female wrestling event in London. England on August 17, 2017. (Photo by Neil Hall/Reuters)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

Actress Scarlett Johansson Honored With The Star On The Hollywood Walk Of Fame on May 2, 2012 in Hollywood, California. (Photo by Jon Kopaloff/FilmMagic)

The Royal Air Force Red Arrows perform the “Gypo Split” during their first public aerobatic display since the tragic death of Flt Lt Jon Egging on September 2, 2011 in Chatsworth, England. (Photo by Christopher Furlong/Getty Images)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)

A boy looks back while he and another boy play on a Syrian military tank, destroyed during fighting with the Rebels, in the Syrian town of Azaz, on the outskirts of Aleppo, Sunday, September 2, 2012. (Photo by Muhammed Muheisen/AP Photo)