Two women wearing bejewelled bras kiss during the annual Sydney Gay and Lesbian Mardi Gras festival in Sydney, Australia March 4, 2017. (Photo by Jason Reed/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)

In this photo taken Wednesday, March 8, 2017, a hospitality staff member pose for photos near the shadow of a tall light pole near the Great Hall of the People where a plenary session of the National People's Congress is held in Beijing, China. (Photo by Ng Han Guan/AP Photo)

Firefighters of the Texas Canyon Hotshot crew fight the Sand Fire on July 23 2016 near Santa Clarita, California. Fueled by temperatures reaching about 108 degrees fahrenheit, the wildfire began yesterday has grown to 11,000 acres. (Photo by David McNew/AFP Photo)

A fishmonger carries a shark on his motorcycle in Padang, West Sumatra, Indonesia August 25, 2016. (Photo by Iggoy el Fitra/Reuters/Antara Foto)

A woman reacts as she attends a funeral ceremony for Mykola Kuliba and Serhiy Baula, servicemen from the “Aydar” battalion, who were killed in the fighting in eastern Ukraine, at Independence Square in central Kiev, Ukraine, May 26, 2016. (Photo by Gleb Garanich/Reuters)

Rutgers Scarlet Knights cheerleaders perform during a game against the Connecticut Huskies at High Point Solutions Stadium on October 6, 2012 in Piscataway, New Jersey. Rutgers defeated Connecticut 19-3. (Photo by Rich Schultz)