A man rides a horse through a bonfire as part of a ritual in honor of Saint Anthony the Abbot, the patron saint of domestic animals, in San Bartolome de Pinares, Spain, Saturday, January 16, 2016. On the eve of Saint Anthony's Day, dozens ride their horses through the narrow cobblestone streets of the small village of San Bartolome during the “Luminarias”, a tradition that dates back 500 years and is meant to purify the animals with the smoke of the bonfires and protect them for the year to come. (Photo by Francisco Seco/AP Photo)

Revellers celebrate the death of Britain's former prime minister Margaret Thatcher in Brixton, south London April 8, 2013. Margaret Thatcher, the “Iron Lady” who transformed Britain and inspired conservatives around the world by radically rolling back the state during her 11 years in power, died on Monday following a stroke. She was 87. (Photo by Olivia Harris/Reuters)

Dr. Anton Lim is interviewed by the media as he holds Kabang, a two-year-old injured mixed breed, upon arrival at the Ninoy Aquino International Airport in Pasay city, south of Manila, Philippines, early Saturday June 8, 2013 from San Francisco, Calif. Kabang lost her snout and upper jaw saving two girls' lives in the Philippines was headed back to its owner following treatment at the University of California, Davis veterinary hospital. (Photo by Bullit Marquez/AP Photo)

The book “Elektroschutz in 132 Bildern” (Electrical Protection in 132 Pictures) was published in Vienna in the early 1900s by a Viennese physician named Stefan Jellinek (1878-1968, a founder of the Electro-Pathological Museum). The pictures are nice and direct and unambiguous; they teach, graphically, that the surest way to kill yourself with electricity is to form a complete path from source (usually the bright red arrow) to ground (the screened back, pink arrow). Arrowheads provide the path for current flow. (Photo by The Vienna Technical Museum)

A pro-democracy protester wearing a Guy Fawkes mask holds a yellow umbrella and a banner in the part of Hong Kong's financial central district protesters are occupying November 2, 2014. The former British colony of Hong Kong, which returned to Chinese rule in 1997, has witnessed a month of protests calling on the Beijing-backed government to keep its promise of introducing universal suffrage. The protests have for the most part been peaceful, with occasional clashes between the student-led protesters and Beijing supporters seeking to move them from the streets. (Photo by Damir Sagolj/Reuters)

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

A five-week-old orphaned Southern Sea Otter pup rests on a rubber mat after arriving at the Shedd Aquarium's Abbott Oceanarium in Chicago, Illinois October 28, 2014 in this handout photo provided to Reuters on November 5, 2014. The stranded pup was found on September 30 on Coastways Beach in California and was rescued the next day to be brought back to health at the Monterey Bay Aquarium. Southern sea otters were listed as “threatened” under the U.S. Endangered Species Act in 1977. (Photo by Brenna Hernandez/Reuters/Shedd Aquarium)

In this photograph taken on Thursday, November 20, 2014, bud tenders Maxwell Bradford, back left, and Emma Attolini display buds in the shape of Christmas trees that are on sale for the holiday season in a recreational marijuana shop in northwest Denver. The nascent marijuana industry in Colorado is targeting holiday shoppers with special deals much like traditional retailers offer. (Photo by David Zalubowski/AP Photo)