Scientists have uncovered the gruesome secret behind Antarctica's infamous Blood Falls – it's alive with the descendants of ancient sea creatures. The eerie crimson waterfall, which pours from the Taylor Glacier into Lake Bonney, has long fascinated researchers with its blood–like appearance. They added: 'These findings indicate that the subglacial brine–fed system at the Taylor Glacier Terminus retains marine–derived biological signatures long after physical separation from the ocean.' Until now, however, there has been little biological proof that the trapped water really had a marine origin. The findings may also help scientists reconstruct Antarctica's ancient history by revealing when seawater became trapped beneath the growing ice sheet.