ON TV: National Geographic's Explorer: Monster Fish of the Congo airs in the United States on Saturday, February 14, at 7 p.m. ET/PT on the National Geographic Channel.

February 13, 2009--Goliath tiger fish, such as the one seen above, are among the uniquely adapted "monster fish" of the Congo River, which winds through several African countries.

A recent, unprecedented river run on the Congo yielded a raft of new discoveries, including different species--some potentially new--in nearly every nook and cranny, scientists announced this week.

The river was also found to be possibly the world's deepest, and its extraordinary changes in depths and currents help explain why it's such a hotbed of fish diversity.


"What we're seeing here is kind of evolution on steroids," said team leader Melanie Stiassny, a fish biologist at the American Museum of Natural History. Stiassny, a member of the National Geographic Society's Conservation Trust, was among the marine and evolutionary biologists, hydrologists, and kayakers who conducted the exhaustive research in summer 2008. (The National Geographic Society owns National Geographic News.)

--Tasha Eichenseher

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