Sumo wrestlers compete during the “Honozumo” ceremonial sumo tournament at the Yasukuni Shrine in Tokyo April 3, 2015. (Photo by Thomas Peter/Reuters)

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

Dancer Chachi Gonzalez arrives at Nickelodeon's 2016 Kids' Choice Awards in Inglewood, California March 12, 2016. (Photo by Mario Anzuoni/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)

A flood-affected couple sits along a flooded roadside under a picture of Jayalalithaa Jayaram, chief minister of the southern Indian state of Tamil Nadu, in Chennai, India, December 6, 2015. (Photo by Anindito Mukherjee/Reuters)

A bird flies over the abandoned giant sculpture of a Buddhist monk in Cha-am outside Hua Hin, 145km south of Bangkok, on February 25, 2021. (Photo by Mladen Antonov/AFP Photo)

Australia's State Emergency Service (SES) personnel gather at the scene of a light plane crash near the Capital Golf Course, in Melbourne, Australia, 22 June 2021. A pilot was injured and rushed to hospital after his light plane crashed shortly after taking off from Moorabbin Airport. (Photo by James Ross/EPA/EFE)

A boat lies on a beach of the Isola Capo Rizzuto marine reserve in Calabria, Italy on November 14, 2021, where many wrecks of vessels used by migrants are abandoned. (Photo by Alessandro Serrano/AGF/Rex Features/Shutterstock)