Mushers and their huskies practice at a forest course ahead of the Aviemore Sled Dog Rally on January 24, 2016 in Feshiebridge, Scotland. Huskies and sledders prepare ahead of the Siberian Husky Club of Great Britain 34th race taking place at Loch Morlich this weekend near Aviemore. (Photo by Jeff J. Mitchell/Getty Images)

Retired Malam Jabba engineer Akbar Ali skis down the piste at the ski resort in Malam Jabba, Pakistan February 7, 2017. Atop the piste of Malam Jabba in Pakistan's once dangerous Swat Valley skiers schuss downhill, a new Chinese-built chairlift ferries tourists to the peak, and a luxury hotel is under construction to replace one torched by the Taliban. (Photo by Caren Firouz/Reuters)

People look at a downhill rider during the Urban Bike Inder Medellin race final at the Comuna 1 shantytown in Medellin, Antioquia department, Colombia on November 19, 2017. (Photo by Joaquin Sarmiento/AFP Photo)

Camelot, with rider Kris Anderson, wins an exhibition race billed as “The Cameltonian” at the Meadowlands Race Track in East Rutherford, New Jersey June 21, 2014. Run by Hedrick's Promotions in Nickerson, Kansas, this is the third year the race has been run at the track, in tandem with an ostrich race. (Photo by Ray Stubblebine/Reuters)

Selena Gomez performs at the MTV Movie Awards. (Photo by Jordan Strauss/Invision for MTV)

Sleeping Anthidium. Female Anthidium punctatum; Size: 7 mm. (Photo by John Hallmén)

In this Wednesday, March, 5, 2014 photo, Afghan female boxers practice at the Kabul Stadium boxing club, Afghanistan. The women, who are 18 and older, don't have much more than determination, and a trainer who runs them through their paces, watches as they spar, corrects their technique, tells them when to jab, how to protect themselves, when to power through with a left and then a right. (Photo by Massoud Hossaini/AP Photo)

A new monorail service in Houston, Texas, ready for its inaugural service. (Photo by Evans/Three Lions/Getty Images). Circa 1950