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Electric Fish 发电鱼

One way that Harold Zakon and his team find fish to study is to put electrical detectors into the bottom of murky streams in Venezuela. This works because certain fish emit pulses of electricity. Discover electric fish -- on today's Earth and Sky.

DB: This is Earth and Sky. You won't feel a shock. In fact, it takes a special instrument to detect the electric pulses made by a group of fish known as "weakly electric fish".

JB: Unlike eels, which zap their prey with electricity, weakly electric fish use electricity to navigate and locate objects -- and other fish. Harold Zakon studies them at the University of Texas at Austin.

Harold Zakon: ... each species has a different pattern, each of the sexes within a species and each individual. If they approached another fish, they could detect its discharge and determine what species, sex and individual it was. If it was a member of their own species, they might even recognize it.

DB: The electrical pulses of these fish might provide some insight into the workings of the human brain. That's because human brains also work electrically. But electrical discharges made by fish are easier to study than the electricity in the brain.

Harold Zakon: You always have to crack the brain and stick an electrode in. Here, the animals just emit this signal, and we can watch these changes and infer what's going on in the membranes of their cells, just from their behavior.

JB: There's more about electric fish and human brains at today's show at earthsky.org. Thanks to the National Science Foundation -- where discoveries begin. We're Block and Byrd for Earth and Sky.