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)

An Iraqi military vehicle passes displaced Iraqi boys returning to their homes in West Mosul's Oreibi neighbourhood after government forces retook control of the area from the Islamic State (IS) group during the ongoing offensive against the jihadists on May 21, 2017. (Photo by Ahmad Al-Rubaye/AFP Photo)

A stork-billed kingfisher (Pelargopsis capensis) is seen perched on a tree during monsoon rain on July 25, 2016 in Bintan, Indonesia. The stork-billed kingfisher is a tree species which is widely but sparsely distributed in the tropical Indian subcontinent and Southeast Asia, from India to Indonesia. This kingfisher is resident throughout its range. It is very large, measuring 35 to 38 cm (14 to 15 in) in length. The adult has a green back, blue wings and tail, and grey head. (Photo by Sijori Images/Barcroft Images)

A member of the 324 Squadron during the Anzac Day dawn service at Coogee Beach in Sydney, Australia on 23 April 2019. Anzac Day, held annually on 25 April, is a national day of remembrance across Australia and New Zealand, which commemorates the people who lost their lives or served in wars and conflicts. The day coincides with the first landing of the Anzacs at Gallipoli, Turkey, in World War One. (Photo by Steven Saphore/Australian Associated Press)

Models perform during a Muslim fashion show an airport train in Jakarta, Indonesia on Thursday, May 2, 2019. The fashion show was held to great to upcoming fasting month of Ramadan, the holiest month in Muslim calendar. (Photo by Tatan Syuflana/AP Photo)

Kyle Larson (42) flips as he makes contact with Jeffrey Earnhardt (81) on the back stretch during a NASCAR Cup Series auto race at Talladega Superspeedway, Sunday, April 28, 2019, in Talladega, Ala. (Photo by Greg McWilliams/AP Photo)

Antonio Banderas attends the photocall for “Pain And Glory (Dolor Y Gloria/Douleur Et Glorie)” during the 72nd annual Cannes Film Festival on May 18, 2019 in Cannes, France. (Photo by Pascal Le Segretain/Getty Images)

Emily Ratajkowski is seen walking her pet Colombo on June 03, 2019 in New York City. (Photo by Say Cheese!/GC Images)