Electric Fish on Verge of Evolutionary Split [View All]

Robert Roy Britt
LiveScience Managing Editor
LiveScience.com
Sat Jun 3, 11:00 AM ET

Electric fish emit weak signals from an organ in their tails that serves as a battery. Different emissions signal aggression, fear or courtship.

While the fish can apparently understand each others' warning signals, "They seem to only choose to mate with other fish having the same signature waveform as their own," explains neurobiologist Matt Arnegard of Cornell University.

But in the Ivindo River in Gabon, Arnegard and colleagues have found fish with the same DNA emitting distinctly different signals. The fish are likely on the verge of splitting into two species, the researchers announced today.

"We think we are seeing evolution in action," Arnegard said.

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