Freida Pinto as Jas Mitra in Showtime's “Guerrilla”, 2016. (Photo by Sky UK Limited/SHOWTIME)

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)

Winter swimmers dressed in ballet costumes pose for a photo before diving into the icy water, during a snowfall at a park in Shenyang, Liaoning province, China on February 15, 2019. (Photo by Reuters/China Stringer Network)

Marina performs on stage at O2 Apollo Manchester on May 10, 2019 in Manchester, England. (Photo by Andrew Benge/Redferns)

A young USA fan smiles ahead of the 2019 Concacaf Gold Cup semifinal football match between USA and Jamaica on July 3, 2019 in Nashville, Tennessee. (Photo by Ricardo Arduengo/AFP Photo)

A member of staff at Morton & Eden holds an extremely rare early Islamic gold coin on Thursday September 12, 2019, which is expected to fetch £1.4m at auction in London. Measuring a 20mm across, about the size of a modern £1 piece, it is one of the world's rarest and most treasured Islamic gold coins from the first dynasty of Islam, the Umayyad gold dinar dated 105h (723AD). (Photo by Victoria Jones/PA Images via Getty Images)

A woman holds up an umbrella and license plates, one that reads “love”, during violent protests between riot police and demonstrators in the Causeway Bay district of Hong Kong on October 1, 2019. The city observes the National Day holiday to mark the 70th anniversary of communist China's founding Strife-torn Hong Kong on October 1 marked the 70th anniversary of communist China's founding with defiant “Day of Grief” protests and fresh clashes with police as pro-democracy activists ignored a ban and took to the streets across the city. (Photo by Nicolas Asfouri/AFP Photo)

A suspected Vietcong is kicked by a Vietnamese soldier holding a rifle as another soldier attempts to tie his hands on October 22, 1965. The prisoner was one of 15 captured October 21 near Xom Chua when government troops raided in the plain of reeds area. Troops killed 43 suspected Vietcong and seized some arms. (Photo by Richard Merron/AP Photo)