Although Piranhas are omnivorous, they are known for their sharp teeth and an aggressive appetite for meat. The total number of piranha species is not known and new species continue to be described. Piranhas range in colour from yellow to steel-grey to bluish to partly red to almost black. Piranhas are normally about 15 to 25 centimetres long 6 to 10 inches , although reported individuals have been found to be up to 41 centimetres 24 inches in length.
Piranhas have a bulldog-like face with a very large lower jaw and many razor-sharp teeth. The teeth are replaceable. When one is broken off, a new one grows in its place. All piranhas have a single row of sharp teeth in both jaws.
Their teeth are tightly packed and interlocking via small cusps and used for rapid puncture and shearing. Piranhas are opportunistic carnivores flesh-eaters. They eat aquatic and land animals that are in the water. Some of their prey includes fish , mollusks, crustaceans, insects , birds, lizards , amphibians, rodents and carrion carcasses.
Piranhas are diurnal most active during the day. Piranhas generally eat smaller fish. Though estimates vary, around 30 species inhabit the lakes and rivers of South America today. A study suggests that modern species diverged from a common ancestor around 9 million years ago. Also, the Atlantic Ocean rose around 5 million years ago, expanding into the flood plains of the Amazon and other South American rivers.
The high salt environment would have been inhospitable to freshwater fish, like piranhas, but some likely escaped upriver to higher altitudes. Genetic analysis suggests that piranhas living above meters in the Amazon have only been around for 3 million years. Piranhas attract a certain type of pet lover, and sometimes when the fish gets too large for its aquarium said pet lover decides its much better off in the local lake. In this manner, piranhas have shown up in waterways around the globe from Great Britain to China to Texas.
Piranhas are known for their razor-sharp teeth and relentless bite. Adults have a single row of interlocking teeth lining the jaw. True piranhas have tricuspid teeth, with a more pronounced middle cuspid or crown, about 4 millimeters tall. The actual tooth enamel structure is similar to that of sharks. But, while sharks replace their teeth individually, piranhas replace teeth in quarters multiple times throughout their lifespan, which reaches up to eight years in captivity. Though they are hardly as menacing as fiction suggests, piranhas do bite with quite a bit of force.
Using a tooth fossil model, they found that piranhas' million-year-old extinct ancestor, Megapiranha paranensis , had a jaw-tip bite force—the force that jaw muscles can exert through the very tip of its jaw—of as high as 1, pounds. For reference, the M. Science notes that T.
Humans and capybaras are only part of the piranha diet if these prey are already dead or dying. The idea that a piranha could rip a human to shreds is probably more legend than fact, too. For the curious, Popular Science spoke to some experts who estimate that stripping the flesh from a pound human in 5 minutes would require approximately to piranhas. The red-bellied piranha female, for example, lays her eggs in a nest that is dug by her mate.
After the male fertilizes the eggs, they attach to plants at the bottom of the water source and hatch within just a few days. Piranhas live up to eight years. The piranha's conservation status has not been assessed by the International Union for Conservation of Nature.
They are not currently considered endangered. The piranha's top and bottom teeth work together like scissors to cut up food. They lose and regrow teeth, much like sharks. Theodore Roosevelt spread a lot of scary information about these fish in his book, "Through the Brazilian Wilderness," about his travels to South America in Piranhas have very strong jaws for clamping down on prey.
The black piranha has the strongest bite force recorded for bony fish, according to this study by scientist Justin R. Grubich and his team. Its opportunistic behavior allows it to adapt to various biotopes. It is timid and not aggressive but it possesses powerful teeth that can cause serious bites, and is therefore, potentially dangerous.
River Monsters. Piranhas are world-famous for their razor-sharp teeth. Native peoples of South America will catch the piranha and use their teeth to make tools and weapons. Even the fisherman who catch these vicious little predators have to be careful when the fish is out of water. A single piranha out of water is still dangerous enough to take off the flesh, or the odd toe, from an unwary fisherman. Adult piranha will eat just about anything - other fish, sick and weakened cattle, even parts of people.
Sickly cattle that have stooped their heads down to drink from the river have been grabbed by the mouth and nose and pulled into the water, completely devoured minutes later.
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