A woman holds newly designed Indonesia Rupiah banknotes after exchanging her old bills at a Bank Indonesia mobile bank in Jakarta, Indonesia December 19, 2016. (Photo by Fatima El-Kareem/Reuters)

South African Sangomas are wizards and witches who are supposedly chosen by their ancestors to follow a traditional training and go through a rite of passage after which they become Sangomas and can cure and help people. They are so respected and trusted that western medical authorities have actually advised the government of South Africa to develop its cooperation with Sangomas in order to improve hygiene and health among the population. (Photo by Patrick Durand/Sygma via Getty Images)

With its huge eyes, comical name and diminutive size, Mark R. Smith’s image of a baby Hawaiian bobtail squid can’t help but raise a smile. A curiously endearing creature, the cephalopod is just 1.5cm across, its mantle cavity bearing more than a passing resemblance to a rather natty shower cap. But it is also a beautiful example of symbiosis – nature’s version of “I’ll scratch your back if you scratch mine” – for on the underside of the squid is a light organ which houses bioluminescent bacteria. The squid offers the bacteria protection and food, while the bacteria emit a glow – a handy trait that the squid uses to offset its silhouette, helping it to evade predators in the depths below. Mark R. Smith’s entry combines several images of a Hawaiian bobtail squid with different focus lengths to create a final picture with greater depth of field than normal. (Photo by Mark R. Smith/Wellcome Images/Macroscopic Solutions)

In this May 2016 photo released by The Ocean Agency/XL Catlin Seaview Survey, a boat sails near a coral reef that has been bleached white by heat stress in the Maldives. oral reefs, unique underwater ecosystems that sustain a quarter of the world's marine species and half a billion people, are dying on an unprecedented scale. Scientists are racing to prevent a complete wipeout within decades. (Photo by The Ocean Agency/XL Catlin Seaview Survey via AP Photo)

People ride a bus as they travel in Yangon, Myanmar January 14, 2017. Picture taken January 14, 2017. (Photo by Soe Zeya Tun/Reuters)

A miniature model of Chichen Itza in Mexico, part of Gulliver's Gate, a miniature world being recreated in a 49,000-square-foot exhibit space in Times Square, is seen during a preview April 10, 2017 in New York City. (Photo by Timothy A. Clary/AFP Photo)

In this Thursday, April 13, 2017, picture entertainers wearing rabbit costumes speak at a fair in Bucharest, Romania. Ahead of Easter, celebrated by both Orthodox and Catholic believers on April 16 processions of priests clad in golden robes carrying foliage on Palm Sunday in a recreation of Jesus' ride into Jerusalem, mixed with more commercial flavored celebrations like an Easter fair outside the giant palace built by late Communist leader Nicolae Ceausescu where entertainers strutted around wearing giant rabbit heads. (Photo by Vadim Ghirda/AP Photo)

From the “Paradise Revisited” story in the November 2013 issue of National Geographic magazine, this image is a beautiful vision of father and son fishermen as they move through the multicolored coral gardens of Kembe Bay, Papua New Guinea, in a traditional outrigger canoe. (Photo by David Doubilet/National Geographic Creative)