EcoWatch: June 8 is World Oceans Day. Its a fitting time to contemplate humanitys evolving relationship with the source of all life. For much of human history, weve affected marine ecosystems primarily by what weve taken out of the seas. The challenge as we encounter warming temperatures and increasing industrial activity will be to manage what we put into them. As a top predator, humans from the tropics to the poles have harvested all forms of marine life, from the smallest shrimp to the largest whales,...