The sunfish is well known to the public since 2015, when a diver captured a scene of "sea lions nibbling on a flatbread" underwater, which left a deep impression. In the picture, the sunfish is chewed like a pie by the sea lion, and there is no sign of resistance and escape during the whole process.
Since then, the sunfish has been jokingly called "sea fool" by netizens as one of the "three fools of sea, land and air", and the other two fools are "lu silly" roe deer and "empty stupid" whale-headed stork.
You know, when weak animals are attacked by predators, they either run away or resist. Animals like the sunfish, even if they are eaten most of their bodies, do not know how to resist, which is really rare. Today, let's take a look at this strange creature.
About the sunfish
The sunfish, also known as the sunfish, is between 3-5.5 meters long and weighs up to 3 tons, making it the largest fish in the bony fish class.
Sunfish is a name for our countrymen, after all, this cargo likes to lie flat on the sea and sunbathe, which looks like a "rolled over car". Its Latin name is "mola", Chinese translated as "line", which was named by the great Swedish naturalist Linner.
Most of the fish in the ocean are spindle-shaped, how suitable for swimming and how to evolve. But the sunfish is somewhat different, with the phrase "look at a line from the front and a large piece from the side" to describe the sunfish, and the overall shape is like a large plate standing in the water.
The fish has a long, pointed fin on its body and belly, and the tail fin is severely degenerated, looking like the back half of the body has been cut off, leaving only a "fish head" floating in the sea. This also reminds me of the dish of fish head bubble cake, but the "fish head" is so big that a pot really can't be stewed.
It is no wonder that in the novel "Twenty Thousand Leagues Under the Sea", there is a very vivid description of the sunfish - "put it in the pot to cook, the pot feels humiliated", mainly because the pot is really not so big.
Loved the "lying flat" sunfish
Some time ago, the word "lying flat" was popular on the Internet, and if you want to say that the natural world is really lying flat, you have to say that the sunfish, because what it often does is to lie on the surface of the sea and sunbathe.
Of course, the life of the sunfish "lying flat" is not passive slackness, but there is another reason.
First, remove parasites from the surface of the body
Scientists have observed that there are more than 40 kinds of parasites on the surface of the body of the sunfish, not only on the surface of the skin, but also in the mouth and orbit are crawling with various parasites, and even smaller parasites appear on the parasites. For their own sake, sunfish float flat on the water, using sunlight and seabirds to remove parasites from their bodies.
Second, replenish body temperature to help digestion
Sunfish feed mainly on plankton, jellyfish and small fish in the ocean, and in order to obtain more food, sunfish have to dive deeper into the water, sometimes even crossing the 100-200 meter deep thermosurface to feed.
As we all know, the farther away from the sea surface, the lower the temperature of the sea, in order to ensure body temperature, the sunfish will float on the surface of the water after each dive foraging, using the sunlight to restore body temperature. In addition, due to the weak digestion ability of sunfish, sun exposure can also allow them to accelerate intestinal peristalsis and help digest food.
When the sunfish is attacked, why does it neither flee nor resist?
I believe that the sunfish will certainly not be willing to be reduced to the rations of other animals, and in the face of danger, not running away and not resisting is not a really stupid sunfish, but it does not have the strength.
First, the sunfish swim slowly
The sunfish swims at a speed of between 0.4 and 0.7 meters per second, and it has little ability to swim compared to many marine animals. Mainly because its ventral and caudal fins have been severely degraded, it can only rely on the strong dorsal and ventral fins for slow swimming.
If you look at the sunfish from the front, you will find that the dorsal fin and the ventral fin are on the same level, much like the stern rudder on a ship that controls the direction. In the face of predators, the sunfish only swings back and forth on the dorsal and abdominal fins, and it is strange that it can run away.
Second, the sunfish have no weapons to resist
The mouth of the sunfish is very small, so that such a small mouth can only swallow jellyfish, plankton, small fish, etc. The main thing is that the sunfish has no teeth, and the mouth cannot be completely closed, and the mouth is always half open. Therefore, when the sunfish is facing danger, it can't do it if it wants to bite back at the predator, even if it bites and tickles.
The size of the large disc is matched with such a "cherry mouth", which looks like an inexplicable sense of violation. But it is undeniable that such a small mouth that can never be closed makes the sunfish look cute and cute.
If they won't run away and won't resist, why haven't the sunfish been exterminated?
Swim slowly, have no ability to resist, just have a "silly big" body, no matter how you look at it, the sunfish is like the product of the failure of natural evolution, and it is a miracle that it can survive until now without being eaten extinct.
However, if nature closes a door for you, it will inevitably open a window for you. The sunfish still survive on Earth with good manners, and naturally have special skills.
First, adult sunfish have few natural enemies
In some ways, the size of the sunfish deters most predators in the ocean. In adulthood, the sunfish can reach a maximum length of five meters and a weight of 3 tons. In terms of size alone, the sunfish stands at the forefront of marine life, except for large marine predators such as killer whales and sharks, other animals dare not easily provoke sunfish.
As for the sunfish that sea lions and seals nibble on, they are mainly juvenile small and medium-sized sunfish.
Interestingly, the newly hatched sunfish is only about 2 mm, weighs only 1 gram, and grows ten million times in size after adulthood, and I have to admire that this product can really grow.
Second, there are many eggs
A female sunfish can lay 300 million eggs at a time, which is the spawning champion among vertebrates, and spawning is mostly the main means for sunfish to continue to continue on earth.
After spawning, the female sunfish completely abandons it and leaves its cubs to fend for themselves. During the time from hatching, to juvenile and adult fish, small sunfish are at risk of being eaten by various fish, especially tuna and loach, and they are used as a good meal.
As a result, the 300 million eggs laid by the sunfish can grow to adulthood in only one millionth, or 300. It is this way of relying on the number of eggs laid and ensuring the survival rate that allows the sunfish to continue on the earth.
Third, sunfish diving experts can avoid predators
Although the sunfish has poor swimming ability, it is a master at diving. They can easily dive to 400 or 500 meters underwater, and the deepest can dive to 800 meters underwater.
The deeper the water, the greater the water pressure, the fewer species of organisms, compared to the diversity of organisms in the upper sea, sharks and killer whales cannot dive so deep to prey on a sunfish.
Fourth, the skin of the sunfish is thick and not delicious
The sunfish has an incredibly thick skin, its skin is composed of dense bone-femoral fibers up to 15 centimeters thick, such a thick fish skin that the average predator can't bite at all.
Even if the skin is bitten, the meat of the sunfish is not delicious, and for predators such as killer whales and sharks, unless they are extremely hungry, they will not have any interest in the sunfish. In addition, the sunfish bone is more meaty, and after removing the skin, the fish on the body is only one-tenth of the body weight.
Say at the end
Although the sunfish has not been extinct, it has become a vulnerable species on the planet, and the reason is that we humans have caused it ourselves.
In marine fisheries, there is a high proportion of by-catch in the form of drifting gillnets and reclaimed water trawls, coupled with the fact that the sunfish are too large, and the fishing boats naturally catch the sunfish after catching a net of fish. Foreign countries do not pay so much attention to it, and naturally they will not put the sunfish back into the sea.
Moreover, the skin of the sunfish is the raw material for boiling gelatin or fish oil, which can be used as a lubricant for precision instruments and machinery, and the cod liver can be made into cod liver oil and edible hydrogenated oil. In the western And South Atlantic, sunfish are a major target for fishermen here.
The sunfish have escaped predators, but not from human nets (desire).