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Miners want to drill for billions of dollars worth of copper and gold beneath the wilderness of America's last wild frontier; fishermen say the world's last great salmon run could be jeopardized.
As sea levels rise, the sunken city of Heracleion sounds a warning of the growing threat faced by the planet's teeming coastal cities.
Conservationists turn killers in this battle to turn back time by eradicating mammal invaders threatening the islands' unique ecosystem.