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Written by Skin
"Didn't scare you?" | Flickr@ David Lehrian
Maybe you don't want to get close to the fish as soon as you see what it looks like, but when you know the secret about its teeth, you will definitely subconsciously stay away from it. Because this grumpy omnivorous fish has a sharp tooth that makes people san crazy.
Ready for the san value to go crazy, slide left. | Wiki
The Ophiodon elongatus is a ferocious omnivorous fish, and for smaller fish and marine life, the Pacific cod is a "bully" because of their appetite to eat everything, including flounder, grouper, crab and squid. In addition, they will even kill each other and eat their own children.
Just look at its teeth and you know that it's a greedy predator because it has more than 500 teeth in its mouth, and these needle-sharp teeth can crush almost anything that's put in its mouth.
Pacific Cod: I declare this ocean my feast |! Wiki
Pacific cod have a set of upper and lower jaws, which are much more flexible than humans, so that they can open their mouths as widely as possible to prey. Moreover, not only did it have a row of teeth, but even the inside of his upper jaw was covered with fangs. These fangs cover all the way down their throats.
When Pacific cod prey, they drag their prey into their mouths before crushing the food with their teeth in their throats.
However, in order to maintain this sharp and good tooth, Pacific cod also had to develop its own dental protection: they have to change more than 20 teeth every day.
The tooth tycoon is the bottom of the direct replacement of the broken! | Wiki
The study, published in a recent issue in the Proceedings of the Royal Society, said that when Pacific cod have dull teeth, they have a hard time catching prey, so losing and replacing teeth becomes their routine.
If you want to study "bullying teeth", you can't let it bite directly. So in this study, the scientists used the method of staining the teeth to visualize the timeline of cod teeth replacement.
Twenty small Pacific cod were placed in fluorescent red pigment jars for 12 hours, so they all had a mouthful of glowing red fangs. For the next 10 days, they were again placed in a fluorescent yellow-green jar. As a result, the initial red teeth are replaced by the green teeth that have been replaced.
Red is the old teeth, green is the new teeth. The dyed teeth are still quite festive. | doi.org/10.1098/rspb.2021.1436
The researchers took pains to count the more than 10,000 teeth in the cod's mouth. However, they eventually found that of the more than 500 teeth in the mouth of Pacific cod, 3.6% of the new teeth were changed every day, that is, about 24 teeth.
And even if they don't eat and their teeth aren't worn, they'll change their teeth. This kind of tooth replacement seems to be as predestined as human teething, and it will be regulated by genes.
In fact, it is not uncommon for fish to change their teeth. Pacific cod may only be considered small bullies, piranhas and sharks are really underwater bosses, and when their teeth are worn, they also need to be replaced in time. But their tooth replacement mechanism is not the same.
One bite of a kitten!
Pacific cod is a bony fish that, like humans, has a hard vertebrae. The seemingly ferocious shark is actually a cartilaginous fish, they have no real bones, the skeleton is made of cartilage.
The cartilage on their bodies is lighter and more elastic, allowing them to move freely and are better able to adapt to the high-pressure environment in the depths of the ocean.
Tough guys also have soft bones. | Pixabay
When bony fish like cod change their teeth, their new teeth will still grow in their original position. But cartilaginous fish are different, their teeth in their mouths are not as hard as we think, more like a kind of scale, with sharp parts to hold the prey in place.
In addition, this tooth does not have a root and is not connected to the nerve, so it can easily fall out. After the falloff, the tooth plate in the back row of their mouths will move forward like a conveyor belt to fill the gap, so that they have a steady stream of good teeth.
There's a dental factory in the shark's mouth that keeps replenishing its teeth forward. | Pixabay
The piranha is the big local tycoon in the tooth exchange world, when one of its teeth is worn, its entire row of teeth will fall out at the same time, directly replaced by a whole row of new teeth.
This is because the entire row of teeth that are joined together will distribute the pressure generated when chewing food evenly across each tooth. If a tooth is broken, an important link is missing from the eating process, and only when all the teeth can work together is it the strongest set of teeth.
A tooth is broken, and it is not fragrant to eat anything. That's right.
In addition to frequent tooth changes, Pacific cod have another quirky feature: some of their flesh is blue-green.
About 20 percent of Pacific cod have this seemingly poisonous blue-green meat. This blue-green color may be due to a pigment called bilirubin.
Cod: I'm so "blue |"! Flickr@Ed Bierman
This pigmentation is likely to be affected by the environment and may also be a survival strategy for fish. For example, some salmon's bright orange flesh is attributed to diet and genetics.
The color of Pacific cod varies from region to region, and energy and energy storage also differ from normal colored fish. Other studies have found that the bilirubin that causes blue-green may also be associated with hunger and stress. Hungry Atlantic cod produce excess blue-green bile in the gallbladder, which penetrates into the intestines.
However, why the Pacific cod has such a magical color is still a mystery.
Although this fish looks scary and strange, it is delicious! Its delicious taste has won the love of many people, and its green fish meat will return to normal color after being cooked, becoming a delicacy on the human table.
Even bullies can't escape the fate of becoming food. | Pixabay
Bully tears: people don't want face, how the final ending is to turn into food!
Cover source: Flickr@ David Lehrian
References: https://docs.qq.com/doc/DU3VzWHpNcmFsSE5k
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