A dog sits in the shade of a mangrove tree as a woman uses a fork to dig for shellfish on the reef-mud flats of a lagoon located at South Tarawa in the central Pacific island nation of Kiribati May 23, 2013. Kiribati consists of a chain of 33 atolls and islands that stand just metres above sea level, spread over a huge expanse of otherwise empty ocean. With surrounding sea levels rising, Kiribati President Anote Tong has predicted his country will likely become uninhabitable in 30-60 years because of inundation and contamination of its freshwater supplies. (Photo by David Gray/Reuters)

Yakutsk, with a population of around 270,000, holds its own title: that of the coldest city on Earth. Here: Frost-encrusted house in the city centre. (Photo by Amos Chapple/Courtesy Images/RFE/RL)

“24.27 N, 81.44 W. These coordinates mark the spot of the final resting place of an old brave soldier, the USS General Hoyt S. Vandenberg. In 2009 it underwent a complete change when the creaky steel monster became a mystical bearer of secrets. In May of that year, the Vandenberg was lowered down into the darkness of the ocean off the coast of Florida to become an artificial reef, where it would dwell in rigor mortis at a depth of 130 feet. This lively, animate, secretive nothingness, this menacing, wild emptiness would haunt and seduce the renowned Austrian photographer and passionate diver Andreas Franke...”. – The Sinking World (Photo by Andreas Franke)

Kira Walkenhorst of Germany (L) signals as Doaa Elghobashy of Egypt (R) watches during the women's Beach Volleyball preliminary pool D game between Ludwig/Walkenhors of Germany and Elghobashy/Nada of Egypt the Rio 2016 Olympic Games at the Beach Volleyball Arena on Copacabana Beach in Rio de Janeiro, Brazil, 07 August 2016. (Photo by Antonio Lacerda/ANSA)

Deaf and hard of hearing people perform a Buddhist Guanyin Thousand Hand dance to mark Sunday's National Day for Helping the Disabled in Yunnan, Kunming province, China on May 19, 2018. (Photo by Wong Campion/Reuters)

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)

First prize. Taken over Bali Barat National Park, Denpasar, Bali. Made with a GoPro Hero 2 camera. (Photo by Capungaero)

Vanessa, thirty-five, had three children with an abusive husband. She “lost her mind, started doing heroin”, after losing the children, who were taken away and given to her mother. The drugs led to homelessness and prostitution. She grew up on Arthur Avenue in the Bronx, but now spends her time in Hunts Point, “trying to survive everyday. Just doing whatever it takes”.