In his series “Ballerinas of Cairo”, photographer Mohamed Taher documents Egyptian dancers making the city streets their stage – pirouetting, leaping and posing their way through their country’s sprawling capital. The photos are, at first glance, stunning snapshots of a city’s vibrant culture in motion. (Photo by Mohamed Taher/Ballerinas of Cairo)

Riot police officers in position to crack down on demonstrators during a protest against Venezuelan President Nicolas Maduro, in Caracas on April 20, 2017. Venezuelan riot police fired tear gas Thursday at groups of protesters seeking to oust President Nicolas Maduro, who have vowed new mass marches after a day of deadly unrest. Police in western Caracas broke up scores of opposition protesters trying to join a larger march, though there was no immediate repeat of Wednesday's violent clashes, which left three people dead. (Photo by Juan Barreto/AFP Photo)

Runners wearing full solid-coloured bodysuits take part in a marathon in Tel Aviv, Israel February 26, 2016. Tens of thousands took part in the event, which saw streets closed off from Rokach Boulevard in the north to Jaffa’s Jerusalem Boulevard in the south. Other than the main 42-kilometer (26-mile) run, the day’s events also included a half-marathon route, several shorter circuits, a handcycle race for the handicapped and a mini-marathon for kids of a single kilometer (0.6 miles). (Photo by Amir Cohen/Reuters)

Supporters celebrate as they watch official results from the Union Election Commission on an LED screen in front of the National League for Democracy Party (NLD) head office in Yangon, November 9, 2015. Myanmar's ruling party conceded defeat in the country's general election on Monday, as the opposition led by democracy figurehead Aung San Suu Kyi appeared on course for a landslide victory that would ensure it can form the next government. "We lost," Union Solidarity and Development Party (USDP) acting chairman Htay Oo told Reuters in an interview a day after the Southeast Asian country's first free nationwide election in a quarter of a century. (Photo by Soe Zeya Tun/Reuters)

(L-R) A man nicknamed "Barcelona", Alexey Bolotov and Alexey Jakushin drink vodka as they travel by a pioneer motorised railcar on their way to Kalach, Sverdlovsk region, Russia October 18, 2015. The "pioneer," a light auxiliary rail vehicle, is a popular form of transport among people who live along the Alapayevsk railway. In a remote corner of the Urals region at the end of a narrow-gauge railway is Kalach, population about a dozen. Three decades ago 600 people called the village home, but the local forestry industry suffered as the former Soviet Union imploded and people moved away in search of work. In Kalach today there are no telephones, no mobile reception and only a few hours of electricity a day. (Photo by Maxim Zmeyev/Reuters)

A Hindu holy man is reflected on a mirror as he prepares a bowl of vermillion powder for devotees near “Sangam”, the confluence of holy rivers of Ganges, Yamuna and the mythical Saraswati, during the annual traditional fair of Magh Mela in Allahabad, in the northern Indian state of Uttar Pradesh, India, Tuesday, January 6, 2015. Hundreds of thousands of devout Hindus are expected to take holy dips at the confluence during the astronomically auspicious period of over 45 days celebrated as Magh Mela. (Photo by Rajesh Kumar Singh/AP Photo)

A British photographer has captured life at the “edge of the world”. Timothy Allen, best known for his work on BBC's Human Planet, trekked through the freezing Siberian wilderness for 16 days as he joined part of an 800km migration of reindeer in the Yamal-Nenets region – a name that roughly translates to “edge of the world”. The stunning pictures feature the nomadic Nenets tribe, who drink blood to survive in -45°C temperatures. Timothy's epic journey, which will be revealed in an eight-minute documentary on Animal Planet USA, saw him travel across the bleak terrain of the frozen Ob River with the Nenets people in December last year. Here: An empty camp is shown beneath a colourful sky in Siberia, December 2016. (Photo by Timothy Allen/Barcroft Productions)

A leader “Rolli” of a yodel group “Schuppel” runs in the snow in front of a farmstead during the “Silvesterchlausen” in the early morning in Urnaesch in the Swiss canton Appenzell Ausserroden on January 13, 2017. (Photo by Michael Buholzer/AFP Photo)