A pigeon sits on the cap of an Indonesian military personnel during a ceremony marking the country's 80th Independence Day, at the Presidential Palace in Jakarta, Indonesia, on August 17, 2025. (Photo by Ajeng Dinar Ulfiana/Reuters)

Contestants compete during their model physique competition to mark International Olympic Day at the Myanmar Convention Center in Yangon, Myanmar, Saturday, June 28, 2025. (Photo by Thein Zaw/AP Photo)

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)

A Kurdish girl celebrates Newroz Day, a festival marking spring and the new year, in Akra, Iraq March 20, 2016. Nowruz is the name of the Iranian New Year also referred to as Persian New Year which is celebrated worldwide by Iranian peoples, along with some other ethno-linguistic groups. Nowruz is the day of the vernal equinox, and marks the beginning of spring in the Northern Hemisphere. It usually occurs on March 21 or the previous/following day, depending on where it is observed. Although having Persian and religious Zoroastrian origins, Nowruz has been celebrated by people from diverse ethno-linguistic communities for thousands of years. (Photo by Ari Jalal/Reuters)

Boys dressed in historical uniforms stand before a military parade in Red Square in Moscow November 7, 2014. The parade marked the anniversary of the 1941 parade when Soviet soldiers marched through the Red Square towards the front lines of World War Two. (Photo by Maxim Shemetov/Reuters)

History enthusiasts dressed as soldiers fight during the re-enactment of Napoleon's famous battle of Austerlitz near the southern Moravian town of Slavkov u Brna November 29, 2014. Hundreds of history enthusiasts took part in the re-enactment of the battle to mark its 209th anniversary. (Photo by David W. Cerny/Reuters)

Henry Leese drives a 1952 British Rail Ivatt number 46512 at Strathspey Steam Railway on August 27, 2013 in Aviemore,Scotland. This year marks the 150th anniversary of the Highland Main Line built as a transportation link to the South for lairds and landowners living in northern Scotland. (Photo by Jeff J. Mitchell)

An India Christian devotee reenacts the sufferings of Jesus Christ on the occasion of Good Friday in Mumbai, India, Friday, March 29, 2013. Christians all over the world are marking Good Friday, the day when Christ was crucified. (Photo by Rajanish Kakade/AP Photo)