Horse racing is part of Naadam, a festival organized every July in Mongolia to celebrate the People’s Revolution. Using children as jockeys in such races has a centuries-long tradition. Boys and girls as young as 5 (although the law imposes a minimum age limit of 7) ride in races that can be dangerous, with hundreds of horses running across the steppe at distances of 12 to 28 kilometres at great speeds. (Photo by Tomasz Gudzowaty)

Flying actor Welly O’Brien poses for pictures as the Southbank Centre launches Unlimited: The Revelation Festival featuring deaf and disabled artists on July 10, 2012 in London, England. (Photo by Neil Mockford)

The 2012 Magic Art Special Exhibition Of China is now open at the Hangzhou Peace International Exhibition and Conference Centre of the Chinese city of Hangzhou.

Photo: Visitors poses with a 3D painting during a show featuring over 50 such works in China on July 20, 2012. (Photo by Associated Press)

Workers put some finishing touches on “Forever Marilyn”, a sculpture by Seward Johnson, on July 14, 2011 in Chicago, Illinois. The stainless steel and aluminum sculpture which stands 26 feet tall and weighs 34,000 pounds will be unveiled tomorrow and remain on display in Chicago through the spring of 2012. The sculpture was inspired by Marilyn Monroe's iconic scene in the 1955 movie “Seven Year Itch”. (Photo by Scott Olson/Getty Images)

Participants enjoy mud during the 14th Annual Boryeong Mud Festival at Daecheon Beach on July 16, 2011 in Boryeong, South Korea. The mud, which is believed to have beneficial effects on the skin due to its mineral content, is sourced from mud flats near Boryeong and transported to the beach by truck. (Photo by Chung Sung-Jun/Getty Images)

“Honorable Mention”. An Indian rhinoceros, far from home and stuck inside with late-winter blues at the Toronto zoo. Photo location: Toronto, Ontario, Canada. (Photo and caption by Stephen De Lisle/National Geographic Photo Contest)

A dog dives during a pet dog swimming contest at the Taoyuan Pet Center on July 31, 2005 in Chengdu of Sichuan Province, southwest China. Over 30 dogs have attended the match. According to state media, with the country's pet population growing fast, analysts predict that the market potential for the “pet economy” in China could reach a minimum of RMB 15 billion (about USD 1.85 billion). (Photo by China Photos/Getty Images)

An American flag flutters on a young tree stripped of bark after a massive tornado passed through the town killing at least 116 people May 24, 2011 in Joplin, Missouri. The tornado that ripped through the town of about 50,000 people May 22, is being called the deadliest single tornado in the U.S. in 60 years. (Photo by Julie Denesha/Getty Images)