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)

Pakistani truck drivers from different cities sit on the roof top of the buildings at Truck station offering Dua before breaking the fast during Holy month of Ramadan in Lahore on April 15, 2021. Ramadan is marked by daily fasting from dawn to sunset Islami's holy month of Ramadan-ul-Mubarak is celebrated by Muslims worldwide marked by fasting, abstaining from foods, sеx and smoking from dawn to dusk for soul cleansing and strengthening the spiritual bond between them and the Almighty. (Photo by Rana Sajid Hussain/Pacific Press/Rex Features/Shutterstock)

Plants grow on houses in the abandoned fishing village of Houtouwan on the island of Shengshan July 26, 2015. Just a handful of people still live in a village on Shengshan Island east of Shanghai that was once home to more than 2,000 fishermen. Every day hundreds of tourists visit Houtouwan, making their way on narrow footpaths past tumbledown houses overtaken by vegetation. The remote village, on one of more than 400 islands in the Shengsi archipelago, was abandoned in the early 1990s as first wealthy residents then others moved away, aiming to leave problems with education and food delivery behind them. (Photo by Damir Sagolj/Reuters)

A motorcyclist ferries a pillion rider sitting on goods in Phnom Penh on June 6, 2017. (Photo by Tang Chhin Sothy/AFP Photo)

A man runs away during a police round up of suspected drug addicts in Kabul, Afghanistan December 27, 2015. Afghan officials have opened a new drug treatment centre in an abandoned NATO military base in Kabul, in the latest attempt to stamp out the country's massive problem of drug abuse. Camp Phoenix, a former training camp on the edges of Kabul set up by the U.S. army in 2003, will take in around 1,000 homeless drug addicts who will receive food, medical attention and treatment, said Public Health Minister Ferozuddin Feroz. (Photo by Ahmad Masood/Reuters)

A Cambodian tuk tuk driver and guide with a tarantula in his mouth shortly after is was dug from the ground on June 7, 2010 in Skuon, Kampong Cham Province, Cambodia. The trade for spiders and other insects as food and for medicinal purposes has been in effect since the 1970's in Cambodia but only very recently have tourists been finding a way to see where the spiders are hunted in the nearby countryside. One guide, who can be found in Kampong Cham Town has started offering tours to tourists who can find him. (Photo by Tim Whitby/Getty Images)

Sеx worker Geraldine, wearing cat make-up, excitedly holds up a dress she is thinking of buying from a street vendor, so that her partner, sitting nearby to keep her company, can see it, as she waits for clients outside the Revolution subway station, in Mexico City, Saturday, March 13, 2021. According to Geraldine, 30, the pandemic has cut clients and increased risks to the sеx workers but has also brought out more assistance for them too, both from dedicated organizations such as the activist group Brigada Callejera or “The Street Brigade” and from individuals who have donated food or clothing. (Photo by Rebecca Blackwell/AP Photo)

An aerial view of the holy Muslim Shiite shrine of Imam Moussa al-Kazim as pilgrims gather to commemorate his death, in the Shiite district of Kazimiyah, Baghdad, Iraq, Wednesday, May 13, 2015. The anniversary of 8th century Shiite Imam Moussa al- Kazim drew tens of thousands of Shiites from all walks to converge on his golden-domed shrine in northern Baghdad. The pilgrims typically march to the shrine while hundreds of tents are erected to offer them free food, drinks and services. (Photo by Hadi Mizban/AP Photo)