When the skinny, small male trout finds the opposite sex, a girl who is 500,000 times heavier than it, it will not let go easily. No matter where the opposite sex appears, the male trout will bite it tightly, fuse his face into the other's body tissue, and then release sperm on the other half for the rest of his life.
There are more than 160 species of deep-sea catfish under the classification, and it is understandable if you mistake the females and males of deep-sea catfish as different animals.
The females of the trout are radiant, and their most notable feature is that they have a glowing "bait" at the front of the head, which helps them attract prey and the opposite sex. Different species of trout have different shapes of bait, and the pattern of light is also different, and the males who wander around can find the same kind of females. The female also has a large mouth of blood basin, the mouth is covered with huge sharp teeth, and the stomach in the body is like a cave to ensure that they can eat and digest whatever prey they encounter in the lonely deep sea.
Different species of trout also vary considerably in body shape. Some of them are slim and streamlined, while others have a face on a spherical stomach, with a funny appearance, like a water balloon in a swimming pool, and have no a life associated with adjectives such as "agile" and "flexible".
Sometimes, females have tiny bumps that look like parasites begging for food. In fact, it is true to say that they are parasites, these things are indeed "parasitic" in their own unique way - those are male fish.
Males are so small that some species of males are even one of the smallest vertebrates in the world ("vertebrates" are vertebrates, corresponding to "invertebrates"—animals without vertebrates)." These lucky males achieved their only goal of a lifetime: to find a female fish that might weigh 500,000 times heavier than them.
In fact, male trouts are unable to eat, and from birth, their task is to find females in the endless darkness, but only about 1% of males succeed, leaving only those who are starved alive. However, because of its small head, the male has the largest nostrils in the animal kingdom, can smell the female, and then firmly hook the female with pincer-like teeth and merge into one for life.
The principle of "fit" between the husband and wife of the trout is as follows: after the male is in place, the enzyme will begin to melt its face, making it one with the female. After contact and fusion with the female's circulatory system, the male will absorb nutrients from the female and continue to grow, while unnecessary organs and structures such as the eyes will shrink. To be precise, males steal nutrients from females, and they are indeed "parasites" for females.
This lifestyle is known as "heterosexual parasitism" – yes, the trout parasitizes "its own people" (there are also several males who are so lucky that they don't blend. After connecting with each other, stealing nutrients and releasing sperm, the male will let go of the female and turn away).
The hormone secretion of the loving couple is also synchronized, that is, the wife can also stimulate the husband to release sperm while releasing the egg cells. Females have 30 feet (about 9.1 m, 1 ft≈30.48 cm) in their egg cells that absorb the male's sperm (since the male also provides something to the female – such as sperm – some biologists believe that the way the squid gets along is not entirely parasitic. Their relationship is also very complicated.)
As a result, the female trout became an auto-fertilized, hermaphrodite species. During her 30-year life, the female was able to combine with several males, all of whom produced sperm for her until the female died. At this time, the entire "complex" will sink into the abyss of the seabed.
This solution to the mating problem can be described as ingenious, but it also turns the trout into a fertility machine, and the husband and wife must constantly produce egg cells and sperm, and do not exhaust the energy of the female fish. This is also why females press their partners in body shape – all because of gametes, i.e. egg cells and sperm.
Humans always think that males are superior to females, and that this is universally accurate, but the truth is that in nature, most species of females will grow larger than males, in part because females spend a lot of energy to produce egg cells. The mouth and stomach of the trout girls are so massive, and because there is a shortage of food in their habitat, the female must ensure that she can eat everything she encounters to obtain energy. In addition, egg cells take up more space than sperm, so it doesn't matter if the male grows relatively small.
In other corners of the animal kingdom, the gametes that a female can produce in a lifetime are quantitative, so egg cells are of great significance, and females must carefully select mating partners. For example, girls may only spend the Spring Festival with the best dancers or the strongest fighters to ensure that the pillow people can pass on the best genes to the next generation. When mammals and other creatures are pregnant with offspring, mothers have to take in more energy to raise the little ones in their stomachs.
The female's pickiness causes the male to fight fiercely for mating rights, which eventually leads to the evolution of "supernormal" shapes in some organisms - in order to defeat the opponent and win the female's heart, the male will eventually grow more burly than the female.
Both the female broad-footed bag shrew and the squid "pick" the opposite sex that is most adapted to the environment in their own unique ways. The former allows the partner to grow majestic testicles, while the latter method really makes the male "scratch his head". Remember I said that only 1% of males can find females before they die? The dead friends were not because they didn't work hard enough—it was so hard to lock a female in the depths of the vast, dim ocean, and only the best tracking masters had the opportunity to blend in with the female and perpetuate their own incense. Presumably this is why the males' nasal passages have been so developed over time, and it is the large nostrils that guarantee their right to transmit genes.
In the early 20th century, the first biologists to observe the trout thought that the female fish was full of her juvenile small fish. But the fish's way of living is so bizarre, it's no wonder scientists come to the wrong conclusions. However, when the truth came out, the initial confusion turned into shock, and then into fear. In 1938, the great naturalist and explorer William Beebe summed up the look of the trout as follows:
In such a vast and intimidating darkness, driven by the smell, a brain rushes to the behemoth-like opposite sex, actively bites a hole in its soft body side, feels the blood of the other party gradually overflowing the blood vessels, and abandons everything that is a fish, commits to becoming a worm, abandons the mind, abandons the feelings - this is pure fantasy, unless the evidence is in front of us, we will never accept it.
Boy, keep swimming, show them the evidence, and don't lose your identity.