Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)

A Polisario fighter sits on a rock at a forward base on the outskirts of Tifariti, Western Sahara, September 9, 2016. At a rocky outpost in Western Sahara, a new generation of soldiers who have never known war are mobilising as tensions resurface in one of Africa's oldest disputes after a quarter century of uneasy peace. (Photo by Zohra Bensemra/Reuters)

Lake Assal is a crater lake in central-western Djibouti. It is located at the western end of Gulf of Tadjoura in the Tadjoura Region, touching Dikhil Region, at the top of the Great Rift Valley, some 120 km (75 mi) west of Djibouti city. Lake Assal is a saline lake which lies 155 m (509 ft) below sea level in the Afar Triangle, making it the lowest point on land in Africa and the third-lowest land depression on Earth after the Dead Sea and Sea of Galilee.

Tens of thousands of HIV positive prostitutes in the slums of Lagos to ensure a rapid spread of the epidemic. “If you arrive by car, you can smell the HIV virus outside”, joked my driver as we are on track to Badia a criminal slums of Lagos. Badia is a corruption of “Bad Area”. Nigerians have a lack of everything, except black humor. The poor West African country Nigeria, with a population of 140 million people, after India and South Africa the highest number of people with HIV / AIDS. (Photo by Ton Koene/Exclusivepix Media)

This 2014 series Shanghai Tian Wa saw Chinese photographer Liu Tao train his lens on two distinct districts in Shanghai. Here: “Shanghai Tian Wai №26, 2014”. (Photo by Liu Tao/The Guardian)

A young woman wearing the summer Kimono, “Yukata” watches the goldfishes during the press preview of “Eco Edo Nihombashi Art Aquarium 2014” exhibition in Tokyo on July 10, 2014. The two-month-long goldfish exhibition will starts July 11. (Photo by Toshifumi Kitamura/AFP Photo)

The new Citroen Concept Car Divine DS is presented at the 2014 Paris Auto Show on October 2, 2014 in Paris on the first of the two press days. European carmakers are hoping to impress with new models at this week's Paris Motor Show and prove they have come out stronger from years of economic trouble and cost-cutting. (Photo by Miguel Medina/AFP Photo)

Models pose for a group photograph outside the Victoria's Secret shop on New Bond Street in central London, December 1, 2014. The 2014 Victoria's Secret Fashion Show will be held in London on Tuesday. (Photo by Andrew Winning/Reuters)