A man reacts after catching a trout with his hands during an event promoting the Ice Festival on a frozen river in Hwacheon, about 20 km (12 miles) south of the demilitarized zone separating the two Koreas, January 10, 2015. The annual ice festival, which is one of the most famous and biggest festivals in South Korea, expects to see more than 1,000,000 people attend. The festival lasts for three weeks from January 10 this year. (Photo by Kim Hong-Ji/Reuters)

Chelsea Hughes, 25, sings at the first annual Underwear Karaoke, an event that pairs two common fears: being seen in your underwear and singing in public, in Los Angeles, California March 12, 2015. (Photo by Lucy Nicholson/Reuters)

American rapper Amala Ratna Zandile Dlamini, known professionally as Doja Cat performs at the 2021 Billboard Music Awards at Microsoft Theater in Los Angeles, California, U.S., May 21, 2021. (Photo by Mario Anzuoni/Reuters)

Taylor Swift performs at the Billboard Music Awards. (Photo by Chris Pizzello/Invision)

Actress Brittany Snow takes a selfie with a fan at The 2015 MTV Movie Awards at Nokia Theatre L.A. Live on April 12, 2015 in Los Angeles, California. (Photo by Jason Merritt/Getty Images)

Host Jennifer Lopez performs during the 2015 American Music Awards in Los Angeles, California November 22, 2015. (Photo by Mario Anzuoni/Reuters)

Singer Taylor Swift poses backstage with her awards for Top Artist, Billboard Chart Achievement Award, Top Female Artist, Top Hot 100 Artist, Top Digital Songs Artist, Top Streaming Song (Video) for “Shake it Off” and Top Billboard 200 Album for “1989” during the 2015 Billboard Music Awards in Las Vegas, Nevada May 17, 2015. (Photo by L. E. Baskow/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)