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 small British company with a dream of building a re-usable space plane has won an important endorsement from the European Space Agency (ESA) after completing key tests on its novel engine technology. Reaction Engines Ltd believes its Sabre engine, which would operate like a jet engine in the atmosphere and a rocket in space, could displace rockets for space access and transform air travel by bringing any destination on Earth to no more than four hours away”. – Chris Wickham via Reuters. Photo: Artist's impression of Skylon. (Photo by Reaction Engines Ltd)

These photos and video were taken in the Russian city of Astrakhan on the evening of June 7th, 2012. (Photo by Maxim Korotshenko)

Meet the real beach babes: the herd of pigs that live a life of luxury paddling in the crystal clear waters of the Bahamas, on August 28, 2013. (Photo by Caters News)

A Palestinian girl watches from the balcony of her house as Israeli soldiers conduct a security operation in the village of Aqraba, east of Nablus in the occupied-West Bank, on May 3, 2021. Suspected Palestinian gunmen carried out a drive-by shooting at a nearby junction the previous, leaving three Israeli civilians wounded, one of them in critical condition, with a manhunt underway. (Photo by Jaafar Ashtiyeh/AFP Photo)

Igor, a 40 year-old Ukranian soldier embraces his wife in front of his military basement in the center of Odessa on March 17, 2022. Odessa, which Ukraine fears could be the next target of Russia's offensive in the south, is the country's main port and is vital for its economy. But the city of one million people close to the Romanian and Moldovan borders also holds a special place in the Russian imagination. (Photo by Bulent Kilic/AFP Photo)

A Chinese woman poses for a photo in front of a flower display dedicated to frontline health care workers during the COVID-19 pandemic that was created with other floral decorations in advance of the country's national holidays, also known as Golden week on September 28, 2020 in Beijing, China. China will celebrate national day marking the founding of the People's Republic of China on October 1st.(Photo by Kevin Frayer/Getty Images)

Girls talk outside the Niavaran Palace in northern Tehran, capital of Iran, March 26, 2024. People visited the Niavaran Palace during the new year vacation of Nowruz, which falls on March 20 this year. (Photo by Xinhua News Agency/Rex Features/Shutterstock)