It’s obvious why the electric eel has its name: it produces electricity. Though other animals are known to produce electricity, no species group has specialized in it better than the electric eel. With its ability to generate electricity, there's almost no other animal like this unique fish. Read on to find out 6 cool facts about this stunning fish.
1. Electric Eels Aren’t Actually Eels
At first glance, the electric eel looks like an eel, but it is anything but. In fact, it is a type of knife fish and is only called an eel due to its slim, streamlined shape. They aren’t even closely related to true eels; recent studies suggest that electric eels are closer to piranhas, tetras, and catfish.
Electric eels are found throughout poorly oxygenated bodies of water throughout Northern South America, including the Amazon basin. Due to the lack of oxygen within their environments, they must breathe through air periodically.
Electric eels sport gills but don’t absorb as much oxygen as from their mouths. Adults prefer feasting on small fish, while juveniles eat mainly invertebrates such as insects and crustaceans. Some other fish species, such as stargazers, torpedo rays, and electric catfish, can all discharge electrical shocks, but no other fish is as specialized in doing so as the electric eel.
2. There are Three Species of the Electric Eel
Until 2019, the electric eel was believed to be just one singular species: Electrophorus electricus. Recent research has shown that the electric eel is made up of three species: Electrophorus electricus, Electrophorus voltai, and Electrophorus varii. Formerly seen as subspecies, all three species have diverged millions of years apart, with E. varii separating from the other two species around seven million years ago. All three species have minor physical differences in appearance but also differ with the strength of electricity they all discharge.
3. Electric Eels Sometimes Hunt in Packs
E. voltai, also known as the Volta’s electric eel (named after Alessandro Volta, inventor of the first battery), has recently shown pack-hunting behavior, previously unknown in the electric eel (and most other fishes). Before this discovery, it was commonly believed that the electric eel was strictly a solitary predator.
In 2019, a large research study was published highlighting the first recorded instance of pack-hunting in electric eels. The eels were found to cooperate, rounding up schools of small fish into what is known as a "bait ball". As soon as the fish are captured, the eels would electrocute them in tandem, shocking them together before catching and gobbling up their prey.
4. Their Shocks are Very Powerful
The Volta’s electric eel produces the strongest volts out of the three species, generating up to 860 V. This high amount is enough to incapacitate a human being. Because of this, electric eels have no known predators.
Despite this, the electric eel’s shock usually doesn’t kill its prey; it merely stuns them. Though volts are enough to pack a punch, the electric eel doesn’t produce enough amperage for its shocks to be lethal. Deaths are usually either from multiple discharges or from drowning. Despite its fearsome reputation, the electric eel is not aggressive and only attacks in self-defense.
Researchers are currently studying the electric eel to utilize their electrical abilities for various forms of technologies, such as batteries and, potentially, artificial human organs.
5. They Use Electricity for Many Purposes
Electric eels sport three electric organs that span throughout their long tails (which make up for around 4/5ths of their body): the main organ, Hunter’s organ, and the Sach’s organ. All their vital organs are situated further toward the front of their bodies. Why it has three separate organs is uncertain, but what is known is that the electric eel produces two types of discharges: high-voltage and low-voltage.
High-voltage shocks are mainly produced by both the main and Hunter’s organs to hunt prey and defend themselves. Electric eels may even leap at their threats to scare them away. Meanwhile, low-voltage shocks are produced by the Sach’s organ and are used to communicate amongst each other as well as navigate through murky waters.
Since these fish are blind, they use electrolocation to sense their murky surroundings and to detect prey. Being mainly nocturnal animals, having poor eyesight would be detrimental in the darkness. Therefore, this fish creates electrical fields almost function as a form of vision. The electric eel even sports polarities on its body, with its tail sporting a negative charge and its head sporting a positive one. Both charges help the electric eel generate an electrical field throughout its surroundings to help navigate.
6. They Were the Inspiration for the First Battery
When creating prototypes for the first batteries, Alessandro Volta attempted to replicate the electric eel’s electric organs through various physical models, experimenting with various types of metals and other materials before subjecting them to a series of electric shocks.
Eventually, these replications would become the world’s first batteries created by humans. Though Volta’s prototypes were inspired, the electric eel’s method of producing electricity is much more complicated and different than how he imagined it; involving a series of electrochemical reactions formed by specialized cells and contractions.