Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

In this February 7, 2014 file photo, Matt Figi hugs and tickles his once severely-ill seven year old daughter Charlotte, as they walk together inside a greenhouse for a special strain of medical marijuana known as Charlotte's Web, which was named after the girl early in her treatment for crippling severe epilepsy, in the mountains west of Colorado Springs, Colo. Colorado is poised to award more than $8 million for medical marijuana research, a step toward addressing complaints that little is known about pot's medical potential. Among the research projects poised for approval on Wednesday, December 17, 2014, are one for pediatric epilepsy patients, and another for children with brain tumors. (Photo by Brennan Linsley/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)

In this September 1, 2014 photo released by the U.S. Geological Survey, fluid lava streams from the June 27 lava flow from the Kilauea volcano in Pahoa, Hawaii. The June 27 lava flow is named for the date it began erupting from a new vent. The Hawaiian Volcano Observatory issued a warning Thursday, September 4, 2014 to a rural community in the path of a lava flow on Hawaii's Big Island, as the molten rock moved to within a mile of homes. Observatory scientists said lava from the Kilauea volcano could reach the Kaohe Homesteads in five to seven days if it continues advancing through cracks in the earth. (Photo by AP Photo/U.S. Geological Survey)

A statue of a Japanese Akita dog named “Hachiko” wearing a face mask is seen near Shibuya Station Wednesday, April 8, 2020, in Tokyo. Japanese Prime Minister Shinzo Abe declared a state of emergency on Tuesday for Tokyo and six other prefectures to ramp up defenses against the spread of the new coronavirus. Hachiko has waited for his owner University of Tokyo Prof. Eizaburo Ueno at the same place by the station every afternoon, expecting him to return home for nearly 11 years even after Ueno's death at work. (Photo by Eugene Hoshiko/AP Photo)

Mohammed El-Dahshan, 38-year-old “Mesaharati”, or dawn caller, accompanies his donkey wrapped with colored led lights to wake Muslims up for a meal before sunrise, during the Islamic holy month of Ramadan, in the Delta city of Dikernis, about 93 miles (150 km) North of Cairo, Egypt early Wednesday, April 12, 2023. Each night, El-Dahshan, sets out after midnight with his donkey banging his drum, chanting traditional religious phrases and calling out on residents by name to wake them in time for the vital pre-dawn meal known as “Suhour”. (Photo by Amr Nabil/AP Photo)

The Wildscreen festival is the world’s biggest celebration of screen-based natural history storytelling which takes place every two years in Bristol. Here: “Walrus in Midnight Sun”. Walrus feed mostly on bivalves in productive, shallow and often sandy habitats in the Arctic. This individual, though, arrived on a beach outside Tromsø, northern Norway, and found comfort on a stranded dead sperm whale. After two weeks he approached Audun, and only half a metre away he stretched his tusk forward and touched his hand gently. “This was one of the most memorable moments of my life”, Rikardsen says. He named the 500kg male Buddy. After two months, the dead whale was decomposed and Buddy suddenly disappeared. (Photo by Audun Rikardsen/Wildscreen 2016)

A heifer, tied with a rope, turns during “Toro de Cuerda” in the white village of Villaluenga del Rosario, southern Spain September 3, 2016. Dazzling clusters of cube-shaped houses perched on top of Andalusia's olive tree-studded mountains, the “Pueblos Blancos”, or white villages, of southern Spain are named for the lime wash the buildings are painted with to keep the interiors cool. The labyrinths of narrow alleyways are a throwback to when this region was known as Al-Andalus and was part of a medieval Muslim territory. While this region is stunningly beautiful and a big draw to tourists visiting the south of Spain, it is also one of the poorest areas in the country and has one of the highest unemployment rates in the European Union. (Photo by Marcelo del Pozo/Reuters)