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The Amazon River is filled with mysterious creatures, and one of those is the piranha. Almost everybody knows what a piranha can do and yes, they're real. They're carnivorous fishes and they can strip ...

A freshwater Amazonian fish has evolved scales with microscopic armorlike structures specially designed to resist a piranha's piercing bite, new research shows. Arapaima gigas is the largest — and ...

Six years ago, the fish ecologist Rodney Rountree was on a skiff in the Peruvian Amazon. He was holding a piranha in his hand…underwater…in a river filled with ...

Diver Alex Reeson checks on the Arapaima or Pirarucu fishes in the tropical section of Europe's biggest freshwater aquarium Aquatis, due to open October 21, in Lausanne, Switzerland. Reuters ...

Researchers in a California biomechanics lab recently staged what should have been the most lopsided freshwater cage match of all time. In one corner was a red ...

This giant red bellied piranha has swum a long way from its native waters of the Amazon - to Devon. The 14in fish died after being dumped in the River Torridge near East Okemont. The Environment ...

Marine biologists have acquired a better understanding of the evolutionary history of piranhas. About 4 million years BP, rise in sea level appears to have brought about the isolation of small ...