Research

Piranha predatory fish change their teeth in whole blocks. But why?

Hearing the phrase "predatory fish", many peopleimmediately remember the huge and bloodthirsty sharks. But the danger for many living creatures is also represented by tiny piranhas that can attack any animal with a whole flock and bite it with their teeth sticking out in all directions. Scientists already know quite a lot about this type of fish, but one feature of their body has always remained a mystery to them. The fact is that piranhas change their teeth not one at a time, but in whole blocks. It turned out that there is a good reason for this.

Piranha films say they are very dangerous. But is it really so?

How dangerous are piranhas to humans?

First, dispel one commonthe myth of piranhas - they are almost harmless to humans. As you know, their body length is a maximum of 50 centimeters, so because of their tiny size, they do not risk attacking large prey. The timidity of piranhas was proven by tropical fish expert Herbert Axeldorf. Once he filled a huge pool with piranhas and dived into the water in the same swimming trunks. Predatory fish did not touch him even when he lowered a piece of raw meat into the water.

It follows that horror films like “Piranha 3D”, where predatory fish devour humans, are sheer lies. Read our material on how filmmakers deceive us.

In addition, in the world there is a huge amountherbivorous piranha, like pacu fish (Colossoma macropomum). Outwardly, they are very similar to their predatory counterparts, but they are very different in their way of life. In particular, we are talking about solitary hunting and eating plankton, insects and all kinds of algae. It is known that the strength of their jaws is enough to crack nuts.

Piranhas of the species Colossoma macropomum do not eat meat

Why are piranha teeth interesting?

Horror movie directors are trying to scare usthe fact that piranhas have large mouths with many teeth sticking out in all directions. Undoubtedly, all this looks frightening, but these jaws can hardly harm people. But these teeth have one strange and very interesting feature - aged, they are replaced with new whole blocks. About why predatory fish need such a jaw feature, was described in a scientific article in the journal Evolution and Development.

It looks like the skeleton of a piranha

Scientists fromUS state of Washington. The team, led by Professor Matthew Colemann, studied 93 skeletons of carnivorous and herbivorous piranha species. Computed tomography, which allows you to look under the skin of any living organism, showed an interesting feature of the body structure of famous fish.

Piranha teeth

Scientists have discovered that the block system updatesteeth found in all types of piranhas. This means that this feature is in no way connected with a predatory way of life and the fish inherited from distant ancestors. The teeth are updated several times during their life, and during the growth of new ones, the old ones remain on them in the form of “caps”. When new teeth grow completely, the block of old teeth completely disappears.

Have you learned anything new about piranha? If you know other interesting facts about these fish, share in the comments or in our Telegram chat. We are grateful!

Piranha teeth cannot fall separatelybecause they are firmly linked. Researchers believe that such an unusual tooth structure is necessary for a uniform load. Thus, they wear out at about the same time. When old teeth fall out, there are already new piranhas in the mouth. This allows them to always be ready for the hunt and protects from hunger.