How terrible is the underwater notorious piranha?

Piranhas, also known as gobys, or piranhas, are a class of omnivorous freshwater fish in the rivers of South America. Piranhas are not a single species of fish, but several species of fish in the family Lipodidae.

They are best known for their sharp teeth and crazy carnal appetite!

Classification of piranhas

Piranhas are a collective term for fish in several genera in the sawfish subfamily, including: sawfish, gluteal carp, jiri sawfish, and sawfish.

The well-known red-bellied piranha

Pygocentrus nattereri

It is a representative species of the genus Cyprinus

The question of how many species of piranhas there are is still unknown and controversial.

First, there is a taxonomic controversy, with some studies suggesting that piranhas should be limited to the genus Sawfish and the genus Slump. Some studies have pointed out that in addition to the four genera previously identified, the genus Sawfish should be added.

Second, new piranha species are still being discovered.

Therefore, the estimated range of the number of piranha species is roughly between thirty and sixty species.

Piranhas are generally 14-26 cm long, with some large individuals reaching 40 cm in length.

Their teeth are tightly arranged in a single layer fixed to the upper and lower frontal bones, and the sharp teeth are easy to pierce and cut off prey.

The teeth are generally triangular, pointed or leafy.

Piranhas are often known as fierce hunters. However, the latest research points out that under the premise that "they are cooperative to complete the hunt", it was found that piranhas are actually a timid fish, they only protect themselves through group actions, and piranhas are often attacked by cormorants, caimans and finless porpoises. "They're just a bunch of ordinary fish with slightly larger teeth."

Researchers studying Lake Viana in Brazil during the rainy season found that piranhas have been eating herbs at some point in their lives, so strictly speaking, piranhas are not carnivorous fish.

Piranhas are an important part of the local ecosystem

It is widely distributed in a variety of environments such as still water and rushing rivers, and sometimes greatly hinders the drainage of local low-lying areas. In the habitat of piranhas, there are often multiple species of piranhas living together.

As a carnivore and scavenger, they feed on plants, fish, bugs and some animals that are larger than themselves, and their presence affects the composition and distribution of local fish population structures.

Some piranhas also feed on plant seeds, which they chew fully, so they do not become propagators of plant seeds.

There are often rumors circulating on the internet that piranhas can chew people or cows to death or eat white bones in tens of seconds. There is also a rumor that piranhas are carnivores attracted to blood. (These rumors often refer specifically to the Nash breech carp, commonly known as the red-bellied piranha.) In addition, the Carey's buttocks are also aggressive, and the sharp teeth can cause severe trauma. ）

These rumors were refuted by The Paper published in Biology Brief by Helder Queiroz and Anne Maguran.

The relationship between piranhas and humans

Studies in Suriname have shown that piranhas occasionally attack humans, but generally only occasionally when the water level is low, there is less food, the density of fish is high, and the colony conflicts with the fish. These reports of attacks on humans usually occur near fishing bays where fish offal or offal are often thrown into the water.

Piranhas can harm swimmers and bathers in the river, often due to accidents caused by the swimmer's personal negligence.

Piranhas also wreak havoc on local commercial and competitive fishing, stealing bait, cannibalizing, destroying nets and equipment, and even attacking humans when caught.

An aquarium experience program

Piranhas are often found in the fish trade and are traded as pets, but this trade is illegal in many parts of the world.

The most common pet piranhas are mostly red-bellied piranhas, and it is very common to be attacked by the same kind of people and have fewer eyes in the piranha during the breeding process, and if the food is not enough, the piranha will eventually eat the same kind.

Piranhas are naturally distributed in the Amazon Basin, the Orinoco River, the rivers of Guyana, the Paraguay River, the Paraná River and the San Francisco River Basin.

They have been introduced to the United States as ornamental fish and have been found to flow into the Potomac River, Lake Ozarks in Missouri and Lake Wennebergo in Connecticut, although these piranhas generally do not survive the cold winters.

Similarly, piranhas have been found in Lake Kaputai in Bangladesh.

In July 2012, the media reported an attack on piranhas near Liujiang in Liuzhou, Guangxi Province.

Some investigations have shown that piranha populations have been dispersed from their original habitats into rivers around the world, and some unscrupulous fish traders have evaded sanctions by scattering piranhas into local waters to avoid being pursued by their own police.

The scariest movie "Piranha"

This is a movie I've seen before, (probably the 1978 version) and it was really young and felt so "scary" after watching it!

A group of small fish can soak the blood of people's bites, subverting my understanding of ferocious animals. Since then, it has also left a shadow in the heart, which has been influenced to this day.

I can swim in the sea, but I never dare to enter rivers, lakes, or even man-made lakes in parks. The muddy water makes me feel uneasy forever.