A car enthusiast races at the Goodwood Revival historic motor racing festival in Goodwood, near Chichester in south England, Britain, September 11, 2015. The three-day event held each September at Goodwood Circuit since 1998 attracts thousands dressed in period costume who watch motor racing in vehicles from the mid-twentieth century heyday of the venue. (Photo by Toby Melville/Reuters)

Indonesian child jockey Egi, 8, poses for photographs as he participates in a traditional horse race marking Indonesia's 70th independence anniversary, in Bima, West Nusa Tenggara province, Indonesia, 08 August 2015. Horse racing is the traditional sport in the area and a cultural heritage which continues to be preserved by the people of Bima, a small city on the east side of Sumbawa island. Similar races also held in Sumbawa Besar regency and Dompu regency. (Photo by Mast Irham/EPA)

A mother bear takes a dip in the water to cool off in the warm summer sun but refuses to leave her three youngsters behind – so they climb aboard her back. (Photo by Jon Langeland/Solent News & Photo Agency)

A woman is assisted by medical personnel during a celebration in the Mission District in San Francisco, California October 29, 2014. The San Francisco Giants beat the Kansas City Royals 3-2 on Wednesday to win their third World Series title in five seasons. (Photo by Robert Galbraith/Reuters)

Gigi Gorgeous presents a creation during the American Heart Association's (AHA) Go Red For Women Red Dress Collection, presented by Macy's at New York Fashion Week February 11, 2016. (Photo by Andrew Kelly/Reuters)

Female Siberian tiger Dasha yawns in the new enclosure at the zoo in Duisburg, Germany, 30 March 2016. The new facility is three times larger than the old one and will be opened to the public on the same day. (Photo by Roland Weihrauch/EPA)

The sun rises over the River Brue on the Somerset Levels as temperatures in parts of the south west drop below freezing, on January, 20, 2015. (Photo by Ben Birchall/PA Wire)