What separated them? Most likely, the Amazon River itself. Around 9 million years ago, after eons of flowing westward, the mighty river started reversing its course. Its modern eastward flow became entrenched around 2. Clear water contains fewer dissolved minerals than muddy water, and is worse at conducting current.
The three species might also behave differently. The National Museum in Rio de Janeiro —the largest natural-history museum in Latin America—was gutted by a fire last year, destroying millions of priceless specimens in a preventable tragedy caused by inadequate funding. About 40, blazes have swept through the Brazilian Amazon this year—an 80 percent rise from last year. David de Santana discovered a small, river-fed lake filled with more than adult electric eels, many of which were upwards of 4 feet long.
On its own, this was an intriguing discovery, electric eels—a type of knifefish rather than true eels—were thought to be solitary creatures. Then groups of up to 10 eels periodically split off to form cooperative hunting parties, not unlike packs of wolves or pods of killer whales. Those smaller groups then surrounded the prey ball and launched simultaneous electric attacks, stunning the tetras into submission.
De Santana is the senior author of a new paper describing this novel behavior in the Jan. The findings overturn the idea that these serpentine fish are exclusively solitary predators and open the door to new questions about how these little-understood fish live.
His pioneering expeditions into the murky, remote waters of the Amazon and its many tributaries have brought to light 85 new species of electric fishes. Just last year, he tripled the number of known species of electric eels , which had stood at one for roughly years. Direct measurements of these simultaneous shocks are one of the things de Santana and his colleagues hope to collect on their next expedition to the remote waterways of the Amazon basin.
Fortunately for de Santana, who has been shocked more than once by individual eels in the field, the shock only lasts about two-thousandths of a second, but it is enough to cause a painful muscle spasm that might knock a person off their feet. Bastos, now a scientist at INPA, discovered a small lake directly connected with the Iriri River, and to his amazement, the lake held more than adult electric eels. Genetic analysis suggests that the E. Electric eels provided Alessandro Volta with inspiration for the first electric battery in , and more recently inspired a battery that could power medical implants.
By Sam Wong Electrophorus voltai is one of the two newly discovered electric eel species L. Sousa An investigation into the diversity of electric eels has produced quite a shock. Despite their serpentine appearance, electric eels are not actually eels. Their scientific classification is closer to carp and catfish. These famous freshwater predators get their name from the enormous electrical charge they can generate to stun prey and dissuade predators.
Their bodies contain electric organs with about 6, specialized cells called electrocytes that store power like tiny batteries. When threatened or attacking prey, these cells will discharge simultaneously. They live in the murky streams and ponds of the Amazon and Orinoco basins of South America, feeding mainly on fish, but also amphibians and even birds and small mammals. As air-breathers, they must come to the surface frequently.
They also have poor eyesight, but can emit a low-level charge, less than 10 volts, which they use like radar to navigate and locate prey. Electric eels can reach huge proportions, exceeding 8 feet in length and 44 pounds in weight.
They have long, cylindrical bodies and flattened heads and are generally dark green or grayish on top with yellowish coloring underneath. Human deaths from electric eels are extremely rare. However, multiple shocks can cause respiratory or heart failure, and people have been known to drown in shallow water after a stunning jolt. All rights reserved.
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