Cubans gather at Havanas Malecon waterfront to watch the fireworks on the eve of the city's 500th anniversary on November 15, 2019, in Havana, Cuba. The fireworks were launched from the opposite side of the Havana bay, at the El Morro fortress and lighthouse complex. (Photo by Sven Creutzmann/Mambo photo/Getty Images)

In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)

A peacock walks next to the Monastery of the Holy Apostles, on the shore of the Sea of Galilee, northern Israel November 30, 2016. About 1 million tourists from abroad visit the Sea of Galilee, also known as Lake Tiberias or Kinneret, each year, according to the Israeli Tourism Ministry. (Photo by Ronen Zvulun/Reuters)

An alpaca is seen near the Inca citadel of Machu Picchu in Cusco December 2, 2014. Machu Picchu, a UNESCO World Heritage Site, is Peru's top tourist attraction, with the government limiting tourists to 2,500 per day due to safety reasons and concerns over the preservation of the ruins. (Photo by Enrique Castro-Mendivil/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)

A supercell thunderstorm develops, May 8, 2017 in Elbert County outside of Limon, Colorado. With funding from the National Science Foundation and other government grants, scientists and meteorologists from the Center for Severe Weather Research try to get close to supercell storms and tornadoes trying to better understand tornado structure and strength, how low-level winds affect and damage buildings, and to learn more about tornado formation and prediction. (Photo by Drew Angerer/Getty Images)

A couple sits on a swing during stormy weather along a beach by the Mediterranean Sea in Gaza City on December 8, 2021. (Photo by Mahmud Hams/AFP Photo)

Aerial view of a clear and turbid landscape at the intersection of the Sanjiang Estuary during the flood season on July 4, 2023 in Nanning, Guangxi Zhuang Autonomous Region of China. (Photo by Chen Guanyan/China News Service/VCG via Getty Images)