Migrants hold placards as they demonstrate, waiting at the buffer zone in front of the Pazarkule border crossing to Greece, in Edirne. AFP / BULENT KILIC

Two polar bear cubs hide behind their mother "Malik" during their first outing at the Polar Bear enclosure in Aalborg Zoo, Denmark. AFP/Ritzau Scanpix/Henning Bagger

A wounded Syrian child sits at a makeshift clinic in the town of Maaret Misrin following Syrian government forces airstrikes in the country's northwestern Idlib province. AFP/Aref TAMMAWI

A member of the Syrian Civil Defence, also known as the "White Helmets", carries a child after she was recovered from debris in the town of Maaret Misrin following Syrian government forces airstrikes in Syria's northwestern Idlib province. AFP/Ahmad al-ATRASH

A woman feeds her granddaughter while other children watch inside their home at Labor Camp community in Lunsar, Sierra Leone. REUTERS/Cooper Inveen

Men daubed in colours take part in "Lathmar Holi" celebrations inside a temple in the town of Barsana, in the northern state of Uttar Pradesh, India. REUTERS/Adnan Abidi