A woman wears a face mask in the part of the city near neighbourhoods known for burning coal for heating in Ulaanbaatar, Mongolia January 26, 2017. Not many people in Ulaanbaatar wear masks to protect themselves against pollution. (Photo by B. Rentsendorj/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)

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 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)

Construction workers walk past a mural in Phnom Penh on September 6, 2022. (Photo by Tang Chhin Sothy/AFP Photo)

A dog poses in traditional Chinese dress on Yaowarat Road in Chinatown on the eve of Lunar New Year on January 20, 2023 in Bangkok, Thailand. The Chinese diaspora of Southeast Asia is celebrating a lively Lunar New Year as COVID-19 restrictions have been removed. It is traditionally a time for people to meet their relatives and take part in celebrations with families. In Thailand, which has a sizeable population of Chinese lineage, people gather with family and celebrate with feasts and visits to temples. (Photo by Lauren DeCicca/Getty Images)

A mannequin's head is covered in a woman dress shop in Kabul, Afghanistan, Monday, December 26, 2022. Under the Taliban, the mannequins in women's dress shops across the Afghan capital Kabul are a haunting sight, their heads cloaked in cloth sacks or wrapped in black plastic bags. The hooded mannequins are one symbol of the Taliban's puritanical rule over Afghanistan. (Photo by Ebrahim Noroozi/AP Photo)

Lava erupts from a crater of Mt. Etna, Europe's largest active volcano, behind Santa Maria della Guardia church in Belpasso, near Catania, in southern Italian island of Sicily, early Friday, June 18, 2021. Since Feb. 16, 2021, Mt. Etna has begun a series of spectacular eruptive episodes. (Photo by Salvatore Allegra/AP Photo)