World of wondersFlirt, date, divorce: The robust romantic lives of birdsOn Valentine's Day we look at their love lives and reveal unique courtship and the reality of separation.World of wondersRare footage shows life through the eyes of polar bearsScientists attached cameras to polar bears to learn how they adapt to a warming planet and found worrying trends.World of wondersPhotographer tells BBC how he captured polar bear photoThe poignant image of a snoozing polar bear won the Wildlife Photographer of the Year People's Choice Award.World of wondersSearching for gold in AlaskaQasa Alom visits Alaska where he searches for gold with a local gold prospector.World of wondersThe monster volcanoes hidden beneath ItalyYou know about Mount Vesuvius, but there's a nearby 'supervolcano' with even more immense scale and power.World of wondersThe Greek Island of geometrical wondersPyrgi is a puzzling medieval village in the middle of the Mediterranean island of Chios, in Greece.World of wondersThe church built for all religionsA journey to the hidden church in Slovenia from WWI that transformed into a symbol of peace.World of wondersThe Mediterranean’s hidden wondersA look at the fascinating hidden world of the Mediterranean depths.World of wondersEarth's spectacular and remote 'capital' of lightningWith storms occurring between 140 to 160 nights a year, it's no wonder the area is a world record holder.World of wonders