Six months after the April 20 Deepwater Horizon explosion, the environment and economy of the entire northern Gulf of Mexico region remain in a state of uncertainty, with overturned livelihoods, out-of-work fishermen, reluctant tourists, widespread emotional anguish and untold damage to the sea and its shores.

It could be years before the spill's true effects are understood. The science is largely scattered about what the roughly 200 million gallons of oil that spewed from BP PLC's blown-out well -- some 170 million gallons of which actually spilled into the Gulf -- will ultimately mean for the animals and plant life that inhabit one of the world's most diverse bodies of water.

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