Holly Rakotondralambo is on a mission to save her native Madagascar from being ripped apart by multinational companies exploiting tar sands for oil.  So she is coming to Scotland this week to confront the bank she blames for backing big oil: Royal Bank of Scotland.  RBS is implicated in the environmental destruction facing Madagascar from tar sands mining,  she said.  We call on them to switch their investments away from these polluting fossil fuels and into renewable energy.  RBS is alleged to have helped finance the French oil giant, Total, with more than ?300 million over the last three years. Total has been exploring two areas of the african island thought to be rich in tar sands, Bemolanga and Tsimiroro in Melaky.  Rakotondralambo, pictured right, is a spokeswoman for an alliance of community groups. Exploiting the tar sands would have  devastating consequences  for people and the environment, she warned. There are fears that drinking water and land could be polluted, while Madagascar s rich and unique wildlife could also be threatened.  Rakotondralambo is speaking at meetings in Glasgow and Edinburgh tomorrow and Tuesday organised by the World Development Movement.  Since the banking crisis in October 2008, RBS has received more than ?45 billion of public money.  The bank insisted that it did not directly fund the mining of tar sands in Madagascar.  a spokesman said:  We regularly review our lending policies with regard to environmental, social and ethical matters and discuss these issues with our customers.