An elephant eats a snack after performing at Ringling Bros and Barnum & Bailey Circus' “Circus Extreme” show at the Mohegan Sun Arena at Casey Plaza in Wilkes-Barre, Pennsylvania, U.S., April 29, 2016. Elephants take a final bow at Ringling Bros and Barnum & Bailey Circus on Sunday, ending a 145-year spectacle that delighted fans but enraged animal activists, who say the highly publicized retirement is not enough. (Photo by Andrew Kelly/Reuters)

Indian Runner ducks march past farm buildings at the Vergenoegd wine estate near Cape Town, South Africa, May 16, 2016. Each day, a quack squad of killer ducks are released for the first of two sorties at South Africa's Vergenoegd wine farm in Stellenbosch. Their mission – seek and destroy thousands of pests out to ruin the season's harvest. Fanning out across the vineyards, some 1,000 Indian Runner ducks hone in on their hidden targets with uncanny precision, locating the tiny white dune snails feasting on budding vines. (Photo by Mike Hutchings/Reuters)

This artist's scoreboard displays a fictional game between Mars and Earth, with Mars in the lead. It refers to the success rate of sending missions to Mars, both as orbiters and landers. Of the previous 39 missions targeted for Mars from around the world, 15 have been successes and 24 failures. For baseball fans, that's a batting average of .385. The United States has had 13 successes out of 18 attempts, or a “batting average” of .722. NASA's Curiosity rover, set to land on the Red Planet the evening of Aug. 5, 2012 PDT (morning of Aug. 6 EDT), will mark the United States' 19th attempt to tackle the challenge of Mars, and the world's 40th attempt. (Image by NASA/JPL-Caltech)

Pottery heads by artist Johan Thunell are displayed at The Affordable Art Fair on March 15, 2012 in London, England. 120 galleries are displaying works costing from £40 – £4000. Photography, paintings, prints and sculptures are on sale from 15–18th March 2012. (Photo by Peter Macdiarmid/Getty Images)

Dancers of the English National Ballet perform MacMillan's The Rite of Spring from Beyond Ballet Russes with costumes by Kinder Aggugini at the Coliseum on March 22, 2012 in London, England. (Photo by Ian Gavan/Getty Images)

School children take photographs as Queen Elizabeth II arrives in Valentine's Park Redbridge as part of her Diamond Jubilee tour of the UK on March 29, 2012 in London, England. (Photo by Chris Jackson/Getty Images)

Gardener Peter Glazebrook poses for photographers with his world record breaking onion at The Harrogate Autumn Flower Show on September 16, 2011 in Harrogate, England. Peter Glazebrook from Newark, Nottinghamshire claimed a Guinness World Record with his giant onion weighing 8.150 kg. (Photo by Christopher Furlong/Getty Images)