Blooms, or proliferation, of jellyfish have shown a substantial, visible impact on coastal populations -- clogged nets for fishermen, stinging waters for tourists, even choked intake lines for power plants -- and recent media reports have created a perception that the world's oceans are experiencing increases in jellyfish due to human activities such as global warming and overharvesting of fish. Now, a new study questions claims that jellyfish are increasing worldwide and suggests claims are not supported with any hard evidence or scientific analyses to date....