“A Little Monkey on the Cliff”. “A cold front hit the Nagano prefecture. I saw a little monkey enduring the cold in Jigokudani Monkey Park. This little monkey is really cute”. (Photo by Hidetoshi Ogata/Smithsonian Photo Contest)

Mount Whaleback iron ore mine 23°21’32.3”S, 119°40’40.1”E. The Mount Whaleback Iron Ore Mine in the Pilbara region of Western Australia. Roughly 98% of the world’s mined iron ore is used to make steel and is thus a significant component in the construction of buildings, automobiles, and appliances such as refrigerators. (Photo by Daily Overview/DigitalGlobe, a Maxar Company)

A Hindu woman worships the Sun god in the waters of a lake during the religious festival of Chhath Puja in Agartala, India, November 13, 2018. (Photo by Jayanta Dey/Reuters)

Transgender actress Aubrey Banks presents a creation from the CHULO underwear collection ahead of CHULO founder and lead designer Ricardo Muniz during the New York Fashion Week, in a show that raised money for transgender and cisgender young women victims of violence, in New York, U.S. February 7, 2019. (Photo by Andrew Kelly/Reuters)

Freida Pinto as Jas Mitra in Showtime's “Guerrilla”, 2016. (Photo by Sky UK Limited/SHOWTIME)

View of an American marine as he lies in a foxhole and whistles at a husky, one of the scouting dogs used during the landing on Guam, August 1944. (Photo by W. Eugene Smith/Time & Life Pictures/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)