Zitteraal study How strong are the electric shocks?
Kenneth Catania of the University of Nashville has self-determined that shivering eels are also giving large mammals strong surges by lifting themselves out of the water.
Alexander von Humboldt's report
Alexander von Humboldt already reported in 1800 on his trip to South America of shaking eels, the horses missed so strong electric shocks that they died.
Fishing with horses
Humboldt had asked Fischer to catch him shaking eels for scientific purposes. The fishermen then drove horses and mules into a water hole. Various shivering eels sprang out of the water, pressed against the horses and delivered electric shocks to them. Several horses collapsed, two drowned.
Many scientists considered Humboldt's portrayal untrustworthy.
Stronger than stun gun
Catania now electrocuted herself and confirmed that it was stronger than a stun gun.
Defense against threats
The electric eels would protect themselves against the threat of electric shock. He writes, "Apparently, for the Eel Hall, a fierce attack is the best defense."
Shaking eels are not eels, but knife fish living in tropical South America.
Generation of electricity at first hand
Evolution has led to a special development in these fish of the Amazon: The body of the eel is filled with the power-generating organs.
Electricity through the body of the victim
Catania had previously demonstrated that shaking eels amplify the force of the surges by leaping out of the water. So they direct the stream from their chin directly into the body of the victim, through the water the stream flows into the tail of the shaking chamber, and the circuit is closed.
Electricity in the water for hunting
Under water, the energy of the stream is distributed. Here, the eel eels launch the thrusts, especially for hunting smaller prey animals. These are paralyzed by the stream and can be eaten so easily.
Electricity outside the water for defense
Outside of the water, however, the eels defend themselves against larger parts of the land, which can be dangerous to them, and whose bodies are partially submerged.
Low water attacks
Catania found that the eels are particularly vulnerable when the water level is low. In the home of animals remained of waters in the dry season, only small ponds in which the "eels" predators without the electrical defense are helplessly exposed.
40 to 50 milliamps
In the provoked attack on his own body produced a small electric eel to 50 milliamps. For example, human pain receptors respond by retracting the arm at five milliamperes.
The biologist says: "It is impressive that a small electric eel can deliver so much electricity. We do not know the exact motive for the behavior, but they must scare off enemies, and I can tell you that they are really good at it. I can not imagine that an animal that has suffered such a shock will stay close. "
How dangerous is the electric eel?
Deadly consequences of electric shock from human echinoderms are unknown. Risky, however, is a possible muscle spasm due to the electric shock under water, which can lead to drowning in deeper water.
Electric shocks can not only be dangerous but also helpful: Minimal electric shocks can significantly reduce pain in migraine headaches. Stimulation with electric current improves the memory.
(Dr. Utz Anhalt)