If the longest river in the world is the Nile River in Africa, then the largest river in the world is the Amazon River – this river has the largest basin and highest water flow in the world. At the same time, the largest tropical rainforest in the world is the Amazon rainforest, most of which is located in Brazil. The two are closely intertwined to create the most diverse flora and fauna on the planet.
The Amazon rainforest is known as the “lungs of the Earth”, the air is quite fresh, there are also lush ancient forests and beautiful winding rivers that attract many people. This. This is home to the most species in the world, with more than 2.5 million species of insects and more than 10,000 species of plants and thousands of mammals such as pythons, golden parrots and freshwater dolphins. ..
But underneath these beautiful scenes and biodiversity, there are extremely scary dangers.
What makes the Amazon River so terrible? And why don’t people dare swim in it?
Besides the fact that the Amazon is home to the giant anaconda and countless other predators, one of the reasons comes from the name “Piranha”.
The Amazon River is famous for the terrifying “Piranha fish”, which has many fangs and a crazy bite force, and can hunt in groups. There are opinions that they can eat a 450 kg cow in 70 seconds. All that remains is the skeleton.
Piranhas are known for their razor-sharp teeth and relentless bite. (The word piranha literally translates to “sawtooth fish” in the Tupí language of Brazil.) True piranhas have tricuspid teeth, with larger/longer incisors.
The shape of Piranha’s teeth is often compared to the shape of a saw’s nose and this has clearly been adapted to suit their carnivorous diet. The actual tooth enamel structure of this fish is similar to the tooth enamel structure of sharks.
It is not uncommon for Piranhas to change their teeth throughout their lives. However, while sharks replace their teeth individually, piranhas replace their teeth and jaws multiple times throughout their lifespan, which lasts up to eight years in captivity. It is not uncommon for Piranha fish to lose half of their lower jaw.
There are many types of Piranha fish and they are both vegetarian and carnivorous. Their common foods include insects, fish, crustaceans, worms, animal carcasses, seeds and other plant materials.
In a 2012 study in the journal Scientific Reports, researchers found that the black (or red-eyed) piranha (Serrasalmus rhombeus), the largest of the modern species, bites with maximum force. is 33 kg (3 times body weight).
Using tooth fossil models, they discovered that the 10-million-year-old extinct ancestor of the Piranha species, Megapiranha paranensis, had a bite force at the tip of the jaw as high as 484 kg. For reference, this Megapiranha paranensis weighed only 10 kg when alive, meaning the bite force of Megapiranha paranensis was almost 50 times its body weight.
Science notes that the estimated bite force of T.rex was three times higher than that of this ancient Piranha (Megapiranha paranensis) – but the “king of reptiles” was T.rex. much heavier.
Not only possessing scary teeth, Piranha fish also possess an extremely intelligent prey attack strategy. A 1972 study of red-bellied piranhas found that the fish most frequently attacked goldfish in a laboratory setting, starting from the prey’s tail or eyes.
The researchers concluded that such an attack strategy would leave the piranha’s opponents immobilized or disoriented.
In addition, one can easily see that Piranhas often move in groups. They do this for safety.
Piranhas are not at the top of the food chain in the Amazon riverbed. They are prey for Caiman crocodiles, birds, river dolphins and other large Pescatarian fish. Therefore, traveling in groups in shallow areas helps protect the fish inside from being attacked.
A 2007 study linked noise, splashing water and spilling food, fish or blood into rivers to three cases of Piranha attacks on humans in Suriname (South American country).
Regarding blood, Piranha fish can smell a drop of blood in 200 liters of water. So, if you have just a minor injury, taking a dip in the Amazon River is not wise!
And although piranhas are famous for attacking humans, there is not much evidence to support this. Like grizzly bears, wolves, sharks, and pretty much any large creature with teeth, Piranhas will leave you alone if you leave them alone.
Black Piranha and Red-bellied Piranha are considered the most dangerous and aggressive species towards humans. However, veteran South American swimmers often emerge from piranha-infested waters without losing their flesh.
For the average person, danger occurs when you move where the water level is low, prey is scarce (for Piranhas) or you disturb its breeding grounds on the river bottom – Basically, this is situations where Piranha feel truly threatened or when they are truly threatened. hungry – therefore they will become more aggressive.
That’s why indigenous people rarely wade barefoot at the river’s edge. For them, hunting and eating Piranha is taboo, so they rarely touch this fish.
Scientists advise amateurs not to go or swim in the Amazon River, to avoid misleading them (being disturbed or potentially dangerous) so they attack humans.
