Why Not Feed the Polar Bears?

When Christopher Columbus first moored in the Caribbean, sea turtles were so plentiful that the sound of their carapaces thumping against the ships’ hulls kept his crew awake at night.As late as the 19th century, passenger pigeons flew in flocks so large they blocked the sun and snapped the branches of trees on which they roosted, and herds of stampeding bison coming across the prairie slammed into trains with enough force to knock boxcars off their tracks.