A sun bear reacts to triple-digit temperatures at the Henry Doorly Zoo in Omaha, Nebraska, where the temperature reached 103 degrees Fahrenheit on July 6, 2012. (Photo by Nati Harnik/Associated Press)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

A tourist crosses flooded St. Mark's Square in Venice, Italy on November 11, 2012. Flooding is common this time of year and Sunday's level that reached a peak of 58.66 inches was below the 63 inches recorded four years ago in the worst flooding in decades. (Photo by Luigi Costantini/Associated Press)

A visiitor bungee jumps during an outdoor festival to celebrate German Unity Day on the 21st anniversary of German reunification on October 3, 2011 in Berlin, Germany. German Unity Day is a national holiday and marks the day West Germany and East Germany were reunited in 1990 following the collapse of the Iron Curtain. (Photo by Adam Berry/Getty Images)

The world's biggest wild animal farmer, Carr Hartley of Rumuruti in Kenya, sells animals to zoos, circuses and film companies. (Photo by Maxim Ruston/BIPs/Getty Images). November 1956

A derelict farm house adorns the horizon as it sits in a field in the Lancashire Countryside on January 26, 2012 in Burscough, England. (Photo by Christopher Furlong/Getty Images)

A hand out picture released by Queensland police on November 7, 2016 shows a police officer taking care of a baby koala in Brisbane Australian police made one of their more unusual finds when they uncovered a baby koala hidden in the bag of a woman they stopped in the street. (Photo by AFP Photo/Queensland Police)

A Free Syrian Army (FSA) fighter reacts as he mourns near the body of his brother, who was an FSA fighter and died during an offensive against Islamic State fighters to take control of Qabasin town, on the outskirts of the northern Syrian town of al-Bab, Syria January 10, 2017. (Photo by Khalil Ashawi/Reuters)