A student falls asleep as she holds a book containing a portrait of China's late chairman Mao Zedong during a lesson at the Democracy Elementary and Middle School in Sitong town, Henan province December 3, 2013. In a remote part of central China, the day starts at the Democracy Elementary and Middle School with a pre-dawn jog, some revolutionary songs and then an activity long since forgotten at other schools: reciting quotations from Mao Zedong's famed “Little Red Book”. While the ruling Communist Party that Mao led continues to hold him in esteem as the leader of the Communist Revolution, his radical policies and teachings have been largely shelved since his death in 1976 in favour of a pro-market approach that has turned China from a backwater into the world's second biggest economy. The 120th anniversary of Mao's birth is on December 26, 2013. (Photo by Carlos Barria/Reuters)

A woman stands at the door of her shanty at a slum in Mumbai, India July 20, 2016. (Photo by Danish Ismail/Reuters)

A four-day old African spurred tortoise, Geochelone sulcata, one of eight babies, was place on the head of its mother in their enclosure in Nyiregyhaza Animal Park in Nyiregyhaza, 226 km east of Budapest, Hungary, 27 September 2011. This was the first time that offspring of an African spurred tortoise were born in this zoo. The eight babies hatched after 115 days, they are 5.5 cms long and weigh 25 grams. Spurred tortoise is the largest species of land tortoises in Africa, the weight of an adult animal may reach 80 kgs. (Photo by Attila Balazs/EPA)

School children wear face masks as they take part in an awareness rally against the use of tobacco on “World No Tobacco Day” in Kolkata on May 31, 2022. (Photo by Dibyangshu Sarkar/AFP Photo)

A girl plays in a water-jets fountain in Moscow, Russia, 23 June 2021. The temperature exceeded 36 degrees Celsius in Moscow. The weather in Moscow broke the temperature record high of the day, held since 1948, when meteorologists recorded +33.6. (Photo by Sergei Ilnitsky/EPA/EFE)

Siberian tigers are fed by visitors from a bus at the Siberian Tiger Park in Harbin, in China's northeastern Heilongjiang province, on January 6, 2023. (Photo by Hector Retamal/AFP Photo)

Naki'o, a mixed-breed dog with four prosthetic devices, goes for a run in Colorado Springs April 12, 2013. Naki'o lost all four feet to frostbite when he was abandoned as a puppy in a foreclosed home. (Photo by Rick Wilking/Reuters)

“The Independence day”. While on storm chasing expeditions in the Tornado Alley in USA I have encountered many photogenic supercell storms. This photograph was taken while we were approaching the storm near Julesburg, Colorado on My 28th, 2013. The storm was tornado warned for more than one hour, but stayed an LP storm through all its cycles and never produced a tornado, just occasional brief funnels, large hail and some rain. Photo location: Julesburg, Colorado, USA. (Photo and caption by Marko Korošec/National Geographic Photo Contest)