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)

A general view of atmosphere at the annual VOLT Festival in Sopron, 208 kms west of Budapest, Hungary on August 16, 2016. (Photo by Rockstar Photographers)

Triplet sisters Natalia, Irina and Tatiana Mironenko attend a rehearsal while preparing for examination performances staged by the graduates of the folk dance faculty of the Krasnoyarsk choreographic college in Krasnoyarsk, Russia May 13, 2019. All three 19-year-old sisters are expected to join the renowned Krasnoyarsk state academic dance ensemble of Siberia after the graduation. (Photo by Ilya Naymushin/Reuters)

A gorilla cube named Pepe eats frozen fruit to fight high temperatures at the Bioparc zoo in Valencia, eastern Spain, 28 June 2019. Spanish peninsula is suffering a heat wave with temperatures reaching up to 45 degrees. (Photo by Kai Foersterling/EPA/EFE/Rex Features/Shutterstock)

A camel performs during a “dance competition” held during the Pushkar Camel Fair in Pushkar, in the western state of Rajasthan, on November 5, 2019. Thousands of livestock traders from the region come to the traditional camel fair where livestock, mainly camels, are traded. The annual camel and livestock fair is one of the world's largest camel fairs. (Photo by Himanshu Sharma/AFP Photo)

A Maori warrior prepares to challenge Prince Charles during his welcome to Takanhanga Marae in Kaikoura, New Zealand November 23, 2019. (Photo by Tracey Nearmy/Reuters)

People take pictures of deer in the Phoenix Park in Dublin, Ireland December 5, 2016. (Photo by Clodagh Kilcoyne/Reuters)