Growing human presence in water will keep encounters rising, scientists say
                                
                                
                                    (Newser) -
                                    Shark populations are way down, but attacks on humans are up, LiveScience reports. There were 71 shark attacks worldwide in 2007, continuing a four-year upswing, says shark expert George Burgess, although populations of the fish have shrunk 50% during the past 20 years. Even so, as human populations expand rapidly,...