Electric eels are one of nature’s coolest animals. Despite their name, they are not actually eels, but a type of fish that is most closely related to carp and catfish. They are the most famous type of electric fish and they use their shocking talents to stun and kill prey and find their way around in the murky rivers they live in. But how do they do it?
Electric eels have a specialized structure called the electric organ in their tails. In this organ, thousands of disc-shaped cells that can produce electricity are lined and stacked up like tiny batteries. These cells are called electrocytes and they work because their outsides are negatively charged compared to their insides. When the eel decides to shock, its electric organ sends out a tiny bit of a neurotransmitter juice that travels along these cells and attracts the negative charges to one side of the cell and the positive charges to the other side. The cells act like batteries and produce a small amount of electricity, but since they are stacked up, they all work together to make a big shock! All 6,000 electrocytes fire within two milliseconds, and the eel sends out a shockwave of more than 600 volts. That’s five times the voltage of a standard wall socket! With this burst of energy, electric eels can stun or kill almost anything they want to eat.
Electric eels also use their electricity to see in their murky river home, like bats use sound to see at night. Electric eels live mostly in the Amazon and Orinoco rivers of South America, and the water is very muddy and difficult to see in. They can fire off little bursts of lower-voltage power from their electric organ, and they use these bursts like radar to navigate the river and find prey. These low-power bursts are usually about 10 volts, or sixty times less powerful than their killing bursts.
Electric eels are not the only kind of electric fish. Certain types of catfish or rays can also emit very powerful bursts of electrical energy to stun and kill prey, and knifefish and elephant-nose rays have electric organs they use to emit low-level electric pulses or waves to navigate and communicate with each other. Some fish, like sharks and catfish, cannot generate electricity but can sense it. They use specialized electroreceptors to sense the very weak electric fields that their prey emit. All in all, fish that use electricity are some of the most awesome animals you will ever find, and electric eels are the brightest stars of the bunch.
Caputi, Angel. "How do electric eels generate a voltage and why do they not get shocked in the process?" Scientific American 5 December 2005: 17.
This article is written by a professor of neuroscience and explains exactly how electric eels work. The language is pretty accessible, but it takes a second read-through to really absorb what it is saying. The author acknowledges that nobody knows exactly why eels do not shock themselves when they discharge, but offers a good possible explanation. I trust the source because Scientific American magazine has a good reputation and won the 2011 National Magazine Award for General Excellence. Overall, this is a concise and helpful article.
"Electric Eel." 2011. National Geographic. 17 October 2011 < http://animals.nationalgeographic.com/animals/fish/electric-eel/. >.
This article is a general description of electric eels: where they live, how they live, and how they shock. It is a good general source for information about electric eels besides how their electricity works, and it also explains the electric shock in clear, easy terms. I like it because it places electric eels in a context and tells you how they discharge in very understandable language. I trust this source because National Geographic is well-known for its scientific excellence. Overall, this is a good, simple, helpful article.
Kawasaki, Masashi. "The Electric Fish." n.d. University of Virginia. 17 October 2011 < http://people.virginia.edu/~mk3u/mk_lab/electric_fish_E.htm. >
This article is by a professor of biology at the University of Virginia and it describes all sorts of electric fish and their types and physiology. The author focuses his own research on weakly electric fish, which I did not really know existed until reading this. It describes how the electric organ works and explains the different ways fish can use this organ, in clear, concise, and easily understandable terms. I also took the animation of how the electric organ works from this site. I trust this source because it is a part of the University of Virginia’s website and the author does personal research in this field. Overall, this article is a good and useful explanation of the different types of electric fish.
"Electric Eel." True Wild Life. 27 October 2011 < http://true-wildlife.blogspot. com/2011/02/electric-eel.html. >
This is a personal blog that focuses on a new animal each day. I did not get much information from this source, but I used one of their pictures. I do not trust the actual information as much as I do with my other sources, because it is a personal site.
