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)
Competitors bear more than their bikinis during a spring break bikini contest at Summers' in Fort Lauderdale, Florida, USA circa 1985. (Photo by Nik Wheeler/Corbis via Getty Images)
A child looks at a polar bear swimming under a water in its enclosure on a hot summer day at Prague Zoo, Czech Republic, July 30, 2015. (Photo by David W. Cerny/Reuters)