Before starting today's knowledge points, let's first imagine the examples around us:
If a man and a woman get married and have children, shouldn't they take care of each other and take care of the family?
The answer is yes, because this is the responsibility of the individual in human society. Not only human society, but you will find the same in the animal kingdom:
Male lions and female lions also distribute their work to each other, one hunting and one feeding; the wild horse leaders of the steppe are also burdened with resisting foreign enemies of the family, and the mare concentrates on eating grass and giving birth to children.
From a macroscopic point of view, this is the "symbiosis" of nature: two individuals together, supporting each other and asking for each other, regardless of who benefits for the time being, in short, the purpose is to let the population continue.
If a husband, who is worthless himself, depends on his wife to support himself, then we call him "eating soft rice." This kind of behavior is despised in our eyes.
But in nature, there is really such a magical animal: they are born to eat soft rice for a living, and even if the wife dislikes them, she can't get rid of it, because in order to eat soft rice, it grows on the wife. This is what we are going to talk about today in the animal kingdom, the first place to eat soft rice: trout!
<h1 class="pgc-h-arrow-right" data-track="8" > when did we know about the trout? </h1>
When I was very young, one of my favorite books every day was called "100,000 Whys", and now that I think about it, the content is really old and outdated. When I was about seven or eight years old, I learned about the fish in the animal book.
The book says: They live in the deep sea, the seabed is dark, and the head of the trout has evolved a small lantern that "will glow", attracting the small fish to get closer, and then swallowing the small fish in one bite.
So this fish took root in my head. When I grew up, I did animal research, thinking that everyone knew what kind of fish the squid was. Until one time eating fish hot pot was asked by peers:
What kind of fish is this squid? Do we want to eat it?
I realized that there were still many people who didn't know it, and I suddenly felt that I had a little responsibility to introduce this "deep-sea strange" fish to everyone.
In fact, in the 80s and 90s, not many people really knew about such things as sturgeon. The first is because the sturgeon lives in deep sea areas below 500 meters, when fishing and transportation capacity are limited, and it is normal not to see sturgeon in cities far from the sea.
Another, more important reason is that the marine ecology at that time was still very healthy. Delicious yellow croaker and striped fish abound, in 1992 China also introduced the turbot (trade name: multi-treasure fish) to breed and sell, people are naturally not interested in the "ugly" and "not delicious" fish of the catfish.
Later, in the 21st century, fishing technology improved, and people began to pursue rare ingredients, so the sturgeon gradually came to the table. In fact, this also reflects the decline of other fish stocks on the side - the sturgeon is actually not delicious.
As a result, the squid that came to the table because of the "general pulling out the shogun" was more and more understood by more and more people.
Now you know why in recent years we can always see the trout always appear in the restaurant, right? (But thanks to this, otherwise many people would not have known about this magical creature.) ）
<h1 class="pgc-h-arrow-right" data-track="19" > Trout: The reason it is called lanternfish</h1>
The sturgeon live in the deep sea, the light can not enter, their first dorsal spine gradually extended forward, specialized into a "fishing rod", the end of the expansion, we call "bait".
The glandular cells in the bait secrete photon, which, under the action of catalytic enzymes, slowly oxidize with the oxygen in the water, which produces a "luminous" effect.
We can understand that the head of the catfish has a small glowing lantern on the top of its head, so they are called "lantern fish". The sturgeon is bulky, slow to move, and alone, making it very difficult to find something to eat in the vast deep sea.
With the help of this small lantern, the sturgeon can attract the small fish in the sea and then quickly open their mouths when they are not paying attention: relying on the strong internal and external pressure difference to suck the small fish near the lantern into their stomachs.
The sturgeon has a stomach that can swell to about the size of its own body and can put down the same food as itself. I think this is also another way to store food, although there is a small lantern, but after all, the prey is not so easy to catch. Catching a large one is enough to digest it for a month.
However, the cold knowledge is that many of these lantern-like trout are actually females. Where did the male squid go? A: Eat soft rice and go!
<h1 class="pgc-h-arrow-right" data-track="26" male squid that eats soft rice >: a magical reproductive parasitism</h1>
There is a great relationship between the size and sex of the sturgeon, and the female trout is often 60 times the length of the male, and the weight difference can be as high as 500,000 times. For example, the female of the dense spiny squid can reach 1-1.2 meters in length, while the male is only 8-16 cm long!
Male sturgeon are typical "soft rice men", they are weak and have no ability to take care of themselves. Partial nostrils and eyes are more developed, relying on the nostrils and eyes to perceive the pheromone emitted by the female squid, and began to live a soft rice life with a dead face.
The male squid first bites the female's stomach (or elsewhere) without letting go, and the circulatory system of its own body and the female's body slowly combines, similar to the fact that we humans have completed an "organ transplant".
At this time, the male squid's physical functions and internal organs will slowly disappear, completely becoming a wife's "parasite", or even leaving only a pair of genitals, and eventually becoming a ruthless breeding machine.
The male attaches himself to the female all his life, and the female has no choice: she can only let her husband absorb her own nutrition.
This is the artifact phenomenon that exists only in the animal kingdom on the body of the trout: reproductive parasitism! We also don't know if it's for breeding or parasitism.
Successfully fertilized female sturgeon will lay eggs in the water, these eggs have hatched, hatched male sturgeon will immediately go to "find a wife", to seize the time to complete the parasitism: because if it is too late, it will either starve to death or be eaten by heaven and earth!
This breeding parasitism was not discovered until 1920 by Icelandic fisherists: because he found that the sturgeon he caught was still dragging his family!
You see on the back of this spiny-headed bare-stick squid, there is a small "male" parasitic.
Although it is famous for eating soft rice, we must also state that not all squid is soft rice. There are 65 species of sturgeon in the world, and different species reproduce in different ways.
The sturgeon is not delicious, but the scientific significance is very large. The medical community is currently deciphering the genes of the trout in an attempt to discover why two individuals share the same system without a rejection response. If the study is successful, it will be an important milestone in human organ transplantation.
From this point of view, eating soft rice for a living does not seem to be useless?