Dark clouds hang over the Great Belt Bridge connecting Nyborg and Halsskov, Denmark, on June 26, 2023. (Photo by Mads Claus Rasmussen/Ritzau Scanpix via AFP Photo)

An old car passes by while dark clouds are seen due to the tropical storm Idalia in Havana, on August 28, 2023. (Photo by Yamil Lage/AFP Photo)

“The Spanish Civil War (The Crusade among Nationalists, Fourth Carlist War among Carlists, The Rebellion or Uprising among Republicans) was a major conflict fought in Spain from 17 July 1936 to 1 April 1939. An estimated total of 500,000 people lost their lives as a consequence of the War”. – Wikipedia. Photo: Actors take part in a re-enactment of the “Battle of Areces” that took place during the Spanish Civil War, in Grullos, north of Spain, September 14, 2013. The re-enactment of the historic 1937 battle was organised by the Frente del Nalon Association. (Photo by Eloy Alonso/Reuters)

“Models decorated with glow-in-the-dark paint manage to stand out in a new series of pictures shot in the dark. Its well known that capturing beautiful photos without natural light is a tricky undertaking even for the most talented photographers but Hid Saib Neto has found a way to make the most of the darkness. The 26-year-old Brazilian photographer covered the group of models in neon paint before illuminating them with just a single ultra-violet light”. – Caters News. Photo: A model wearing the neon make up. (Photo by Hid Saib Neto/Caters News)

Imagine living in the sea where it is permanently dark, cold, and food is hard to find. For many animals at depth, it may be weeks to months between meals. If you find something to eat, you have to hang on to it. This is why so many deep-sea fishes have lots of big teeth. This dragonfish, spotted off the coast of Australia, even has teeth on its tongue. They would be terrifying animals ... if they weren’t the size of a banana. (Photo by Julian Finn/Museum Victoria)

The bloodwood tree (Pterocarpus angolensis) is a deciduous tree with a high canopy, reaching about 15m in height and has dark bark. The red sap is used traditionally as a dye and in some areas mixed with animal fat to make a cosmetic for faces and bodies. It is also believed to have magical properties for the curing of problems concerning blood, apparently because of its close resemblance to blood. The name bloodwood for these trees stems from the dark red to brown sap that accumulates on wounds on the trunks.

Participants of the the goth festival “Wave Gothic Festival” walk in fancy costumes along the festival area in Leipzig, central Germany, Saturday, May 23, 2015. About 20,000 members of the scene are expected to attend one of the world's largest gothic and “dark” culture festivals until May 25, 2015. (Photo by Jens Meyer/AP Photo)