Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

Young Slovaks dressed in traditional costumes throw a bucket of water at a girl as part of Easter celebrations in the village of Trencianska Tepla, Slovakia, April 9, 2012. Slovakia's men splash women with water to symbolize youth, strength and beauty for the upcoming spring season. (Photo by Samuel Kubani/AFP)

Two rescued pangolins sit in a basket during a news conference in Bangkok on June 7, 2012. Thai customs rescued 110 pangolins worth about $35,500 that they say were to be sold outside the country as exotic food. The animals, hidden in a pickup truck, were seized at a customs checkpoint in Prachuap Khiri Khan province, south of Bangkok. (Photo by Sakchai Lalit/Associated Press)

A resident carries a gas canister as an ash cloud hovers above during an eruption of Mount Sinabung volcano at Tiga Serangkai village in Karo Regency, North Sumatra province, Indonesia June 24, 2015. More than 10,000 people from 12 villages, who are living around the slopes of Mount Sinabung, left their homes and moved to refugee camps, local media reported. (Photo by Reuters/Beawiharta)

A picture made available on 17 July 2015 shows the bright line of the Milky Way above the old oaks at the Rogalin landscape Park in Rogalin village, near Poznan, on the night of 16 July 2015. (Photo by Lukasz Ogrodowczyk/EPA)

A leopard leaps into a muddy waterhole to catch a fish on August 13, 2015, in the Savuti Channel in Botswana. A leopard leaps into a muddy waterhole to catch a fish in the Savuti Channel in Botswana. The spotted predator stood poised waiting for a fish to appear – before leaping in ferociously with lightening reflexes. Coated in a layer of thick dark mud the big cat emerged from the water clutching the fish in its jaws. The fishing leopards of Savuti are known for their unique skills in catching fish – but have rarely been photographed. (Photo by Greatstock/Barcroft Media)

A student from the union territory of Pondicherry prepares to take part in the inaugural session of the national Balrang Festival 2017 in Bhopal, India, 20 December 2017. More than 500 participants from 26 states across the country take part in the three-day long cultural event to showcase their performances. The festival organised by Madhya Pradesh School Education Department and Indira Gandhi Rashtriya Manav Sangralaya. (Photo by Sanjeev Gupta/EPA/EFE)

Eddie Ladd and Gwyn Emberton perform as Dylan and Caitlin Thomas in “Caitlin” at the Lauriston Hall, Edinburgh, Scotland on August 25 2017. (Photo by Mary Turner/Reuters)