An iguana in Bali helped Julij Kopilović, age eight, from Slovenia, earn second runner-up in Amazing Animals. (Photo by Julij Kopilović/National Geographic)

Kaw-Claa, a Tlingit native woman in full potlatch dancing costume, 1906. (Photo by Case & Draper/Buyenlarge/Getty Images)

A dancer waits to perform during festivities marking the start of the annual harvest festival of “Onam” in Kochi, India, August 19, 2015. The ten-day-long Hindu festival is celebrated annually in India's southern coastal state of Kerala to commemorate the return of King Mahabali to his beloved subjects. (Photo by Sivaram V/Reuters)

A huge atlas moth, with a wingspan of more than 9in, photographed on an areca nut plantation in Sirsi, India. (Photo by Uday Hegde/Close Up Photographer of the Year)

Michael O’Neill won a prize in animal portraits with fry of a peacock bass hovering around their mother for protection against predators in South Florida. (Photo by Michael Patrick O'Neill/2016 National Geographic Nature Photographer of the Year)

Fossil records indicate that this early lizard, Megalania (Megalania prisca or Varanus priscus), was a whopping seven metres in length. They were part of a megafaunal assemblage that inhabited southern Australia during the Pleistocene. The youngest fossil remains date to around 50,000 years ago. The first aboriginal settlers of Australia might have encountered them and been a factor in their extinction. (Photo by Sky TV/The Guardian)

Two cats watch a mouse walking on the pavement in Kuwait City on March 8,2017. (Photo by Yasser Al-Zayyat/AFP Photo)

A Hawaiian cleaner wrasse provides its cleaning services to a yellowfin goatfish in a reef community off the Big Island in Hawaii. Cleaner species help rid their hosts of ectoparasites, dead tissue, bacteria and fungi. Studies have shown cleaning to play a vital role in keeping many reef ecosystems healthy. (Photo by Marty Snyderman/Caters News Agency)