Most electric eels are actually not even eels. They’re knife fish, which are a type of fish that has a long body and swims with its pelvic fins, rather than with its tail as most other fish do.
Male and female electric eels will find each other by following their sense of smell. When they find each other, they’ll swim up to each other and spawn, depositing their eggs into the water. The eggs will then develop into larvae and then hatch into fry.
The fry will live in freshwater ponds until they’re mature enough to survive in saltwater. They’ll then spend the rest of their lives near shore or in estuaries where they can mate but remain safe from predators while they grow larger than those predators could handle.
If you have ever wondered how electric eels reproduce, you are not alone. In fact, it is an ongoing debate among biologists and other scientists. Here are some of the details of these fascinating creatures. The answer to this question may surprise you. In this article, you’ll learn about Electrophorus electricus, Brachyhypopomus bennetti, and Brachyhypopomus walteri.
Electrophorus electricus
Electrophorus electricus, or electric teleost, is a freshwater teleost that lives in the Amazon and Orinoco basins in northeastern South America. The species is unable to live in deep water and therefore must surface frequently to breathe. One of its unique characteristics is its ability to reproduce by releasing high-voltage pulses from its main electric organ. These pulses are harmless to humans but are highly effective at deterring predators.
These eel species are found in the Amazon Basin, primarily in the northern and central regions of Brazil and French Guiana. The electric eel is an excellent example of a modern predatory fish because it is able to survive in water with very low levels of oxygen.
The electric eel is unique among freshwater teleosts because of its ability to generate electric discharges. It has three distinct electric organs, and these organs are formed from muscle tissue, with sarcolemma-like morphology. The electric organs contain cytoskeletal filaments that contribute to the polarized organization of the electrocyte. The electrolytes express the proteins desmin and actin.
Electric eels are nocturnal and live in freshwater habitats in Mexico and South America. They belong to the knife fish family but are related more closely to catfish and carp than true eels. According to Carlos David de Santana, an associate researcher at the US National Museum of Natural History, the electric eel is a unique example of a nocturnal fish that has evolved to use electric organs in predation and defense.
Although electrophorus electricus reproduces by smell, it also uses other forms of communication. The electric rays it sends out stimulate motor neurons in prey near its body. This may play an important role in mate selection. Furthermore, the electric eel has a remarkable sense of sound, and its Weberian apparatus, which is attached to the swim bladder, greatly enhances its sense of hearing.
Electrophorus electricus has a number of genomic changes that may be involved in adaptation to its environment. One of these changes is the amino acid substitution in the sodium pump a2 subunit. This change is also found in squid and is believed to enhance sodium transport. While the exact role of sodium transport remains to be determined, this genetic change is specific to E. electricus and the only squid species that shares this substitution.
Interestingly, electrophorus electricus expresses a novel miRNA, known as mir-11054. This miRNA is located on scaffold 5041 of the E. electricus genome and is highly expressed in electric organs. This discovery may shed light on the molecular mechanisms involved in the modification of the muscle program.
Several transcription factors from E. electricus were found to be highly upregulated. These factors provided binding sites for cluster 9 genes. The DNA binding sites for the transcription factors are assumed to be similar to those found in MatBase. The exact significance of these factors has yet to be determined, but they are likely involved in EO identity.
Reproduction
Electric eels have an incredible ability to generate electricity. They can direct the combined energy of thousands of generating cells into a single electrical current that can reach 600 volts. The electric eel’s mechanism of generating energy is similar to that of neurons, which transmit electrical signals. They generate the electrical charge by triggering ion channels in the cell membrane. These ions pump some ions into the cell and others out, creating a difference in potential within the cell and outside. This difference stimulates the work of mass of other channels. As a result, the signal is propagated along the membrane of the neuron in a process called autocatalysis.
Male electric eels mate with females and lay up to 1,700 eggs a year. Female electric eels then die and the eggs are fertilized by the male. The eggs hatch into larvae and are able to live independently after a year or two. Electric eels have a long life span, as they begin their lives in the Sargasso Sea and eventually migrate inland following ocean currents.
These fish are capable of producing intermittent electric shocks for many hours without tiring. They can also vary the intensity of their electric current, using lower ones for hunting, and higher ones for stunning their prey. When they reproduce, they must be fed regularly, and they must be allowed to rise to the surface to breathe. Oftentimes, the fish will surround their parent’s head, but their orientation organs have not developed yet.
The electric eel’s body is elongated, cylindrical, and has almost no scales. It has an elongated head with no gills and is flat. The eel’s intestines contain hundreds of thousands of electrolytes that are connected to one another, which causes it to be electric. These electrolytes cause the electric current in the eel.
Electric eels use a voltage of 300 to 600 V to produce an electrical discharge. These electric discharges are short, lasting a few thousandths of a second, and are generated by a pair of oblong organs located on the fish’s spine. The electric organ is a gelatinous, reddish-yellow mass that accounts for 30 percent of the fish’s body weight.
Brachyhypopomus walteri
The species Brachyhypopomus Walter, found in freshwater habitats, reproduces sexually. It has a relatively low fecundity and has a seasonal breeding schedule. It feeds on autochthonous insects. This species is an invertebrate that lives in the tropical regions of the world.
Both species of electrical fish produce electric organ discharges (EOD), which can vary in amplitude and duration in response to different stimuli. This plasticity is conserved among related species. EODs in these fish are usually monophasic, but they can also have complex waveforms with biphasic and multiphasic action potentials.
Brachyhypopomus bennetti
Researchers have found that the electric organ in Brachyhypopomus Bennett, a species of smelt fish, plays an important role in the reproduction of this fish. Its long, thin tail is covered with an organ that emits an alternating current. The organ is located along the body, near the anal fin, and occupies a depth of 14-17% of the fish’s body. The electric organ produces a characteristic discharge waveform which is usually 2.1 millimeters in duration.
This fish’s ancestral habitat likely resembled a low-conductivity, normoxic stream system. However, over time it has evolved to live in a variety of habitats, including habitats with high conductivity and hypoxic conditions. As a result, several species of Brachyhypopomus are eurytopic, meaning that they have a wider range of geographic range than stenotopic species.
The electrical signals produced by Brachyhypopomus Bennett’s are weak and monophasic, which is rare among weakly electric fishes. This feature may make them vulnerable to electroreceptive predators and put them at risk of predation. In addition, the fish’s preference for floating meadows puts them at risk for tail grazing.
The electrical emissions of this fish may be reflective of changes in water conductivity. This may explain why the Electric Eel and Brachyhypopomus Bennett coexist in the same floating meadows. The Electric Eel, however, is a predator and may be a threat to the species.
During the breeding season, the rate of EOD modulations increases tenfold. Moreover, the rate of chirps increases during male-female mating. The underlying mechanism of EOD modulation in this fish is believed to be glutamatergic transmission and androgen binding in the PN. The injection of glutamate into the ventral PN triggers interruptions in females, while it induces chirping in breeding males.
The electrolytes of B. bennetti reproduce by electrical activity. The electrical activity in these electrolytes is associated with Na+ channels. The presence of Na+ channels in the anterior membrane of B. bennetti electrocytes may contribute to the cell’s depolarization.
Biphasic and monophasic EODs have been suggested as mechanisms of cloaking the fish from electroreceptive predators. However, the biphasic EODs sum at close distances to the fish, whereas DC-balanced EODs are undetectable to predators. This may explain the reversion to monophasic EOD in B. bennetti, which has a large amplitude and a low DC component.
The adrenocorticotropic hormone regulates the electrophysiological activity of B. bennetti. Researchers found that the levels of an adrenocorticotropic hormone produced by B. Bennett were increased by about 5%. They also found that the level of electric discharge in B. brevirostris increased in two to three weeks.