In this November 28, 1966 file photo, one of the 10 beagles involved in the first test of the Veterans Administration Hospital in East Orange, N.J. smokes a cigarette through a machine linked to its windpipe by a plastic tube to test any link between smoking and emphysema. (Photo by AP Photo)

Skeleton involves a person riding a small sled down a frozen track while lying face down. The sport is a more intense form of luge because skeleton competitors leap onto the sled and slide downhill head first. Skeleton athletes can reach up to 80 mph on straightaways, causing forces up to 5g, so the helmet is a critical component for attitude as well as safety.

A visitor passes behind the sculpture “Puma-Dentist” made with plastic, wax and original heads of a puma and a hind by Austrian artist Deborah Sengl during an exhibition at the art gallery Deschler in Berlin April 15, 2008. (Photo by Fabrizio Bensch/Reuters)

“I think as mothers we are all just trying our best”. – Gisele Bundchen. (Photo by Mads Nissen/AFP Photo)

Hungarian Puli sheep dog, Fee, jumps over a hurdle during a preview for a pedigree dog show in Dortmund on Thursday April 24, 2008. (Photo by Frank Augstein/AP Photo)

A fisherwoman prepares a meal in her home in a fishing village in Virar, about 40 km (25 miles) from Mumbai December 27, 2005. (Photo by Adeel Halim/Reuters)

Aerial view of flower fields near the Keukenhof park, also known as the Garden of Europe, in Lisse April 9, 2014. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. (Photo by Yves Herman/Reuters)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)