A high temperature alerts were issued as a record-setting summer heat wave continued to bake most parts of south China. (Reuters)

Residents observe a police officer take up position during an operation at the Mare slums complex in Rio de Janeiro March 25, 2014. The federal troops have taken control of security operations in Mare slums complex to help quell a surge in violent crime following attacks by drug traffickers on police posts in three slums on the north side of the city, government officials said. (Photo by Ricardo Moraes/Reuters)

Three-month old cheetah cubs make their public debut at the Smithsonian National Zoo on July 24, 2012 in Washington, DC. (Photo by T.J. Kirkpatrick)

A baby Chimpanzee plays in its enclosure at Taronga Zoo July 14, 2006 in Sydney, Australia. (Photo by Ian Waldie/Getty Images)

German field telegraph operators at work in Warsaw. (Photo by Hulton Archive/Getty Images). 1st October 1914

The sun rises between Sgurr nan Gillean and Knight’s Peak, Black Cuillin, Isle of Skye. (Photo by Adrian Trendall/Mountain Photo of the Year)

This photo of an elephant seal and Gentoo penguin shot by Andrew James in Yankee Harbour, Antarctica. (Photo by Andrew James/Travel Photographer of the Year)