A Hindu holy man, or sadhu, sits beside a fire after smearing his body with ashes at the premises of Pashupatinath Temple, ahead of the Shivaratri festival in Kathmandu, Nepal February 21, 2017. Hindus mark the Maha Shivratri festival by offering special prayers and fasting, with sadhus arriving at Pashupatinath to take part in the event, which takes place on February 24. (Photo by Navesh Chitrakar/Reuters)

Members of the New Orleans Baby Doll Ladies march during the Krewe of Zulu parade at Mardi Gras in New Orleans, Louisiana U.S., February 28, 2017. (Photo by Shannon Stapleton/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)

General view at the Red Bull Music Academy x Mangrove float at Notting Hill Carnival on August 28, 2017 in London, England. The Notting Hill Carnival has taken place since 1966 and now has an attendance of over two million people. (Photo by Tristan Fewings/Getty Images for RedBull)

A customer touches an adult sеx toy doll at a stall during the Asia Adult Expo in Hong Kong on August 30, 2017. (Photo by Jayne Russell/The Sun)

A brown capuchin monkey holds a fruit in the Botanic Garden of Rio de Janeiro, Brazil, on July 5, 2013. (Photo by Pablo Porciuncula/AFP Photo)

Dakar Rally, 2017 Paraguay-Bolivia-Argentina Dakar rally, 39th Dakar Edition, First stage from Asuncion, Paraguay to Resistencia, Argentina on January 2, 2017. Adrien Metge of France pushes his Sherco. (Photo by Ricardo Moraes/Reuters)

Kimono-clad women enjoy the view from Tokyo Sky Tree’s 350-meter-high observation deck in Sumida Ward, Tokyo, on the Coming of Age Day, January 9, 2017. Sumida Ward invited about 430 local 20-year-old to the deck to celebrate them. Many city governments invite local 20-years-old to there’s symbolic places and celebrate for their Coming of Age Day. (Photo by The Yomiuri Shimbun via AP Images)