introduction
The large fish in the water are not only reflected in the species of fish, but also in the production of fish. The vitality of the fish is really tenacious, as if there is water and there is fish, the Red Army on the road of the twenty-five thousand miles long march, through a muddy swamp, where the cooking squad leader catches small fish, cooks fish soup for the sick little Red Army soldiers to drink. In this place where people are rare and birds don't, how can there be fish, there are many small fish, because this body of water is not large.
A picture of a lot of big fish in the water
If there are more species of large fish in the water body, there are often large fish. Everyone also knows that it is impossible for someone to carry fry to be stocked in this mud swamp in this harsh environment, but how did this small fish come from? Also, I often hear the old man say that going to a deep mountain forest to dig a large pond for irrigating planted fruits and vegetables or irrigating newly reclaimed crops, after a long time, there will be fish in the pond, everyone thinks that weed seeds become fish, is this really the case? Is nature really intrigued? Could it be that plant seeds can mutate into moving fish? Is there something out of nothing? If you want to thoroughly understand the reasons, let me explain it systematically, starting from the structure of fish, talking about the relationship between mermaids, talking about the way fish reproduce, talking about the magic of nature, and talking about the transmission of fish.
Fish construction
Diagram of the structure of fish
The head, torso, and tail are general components of fish. Fish breathe with gills, from the mouth into the gills outflow, the direction of water flow is exactly the opposite direction of blood flow in the gill plate, the formation of a countercurrent exchange system can efficiently bring both oxygen and carbon dioxide.
You may ask a lot of questions, some animals with fish characters are not actually fish, crocodiles, turtles belong to reptiles, whales belong to mammals. Everyone's knowledge is very profound, and then some people will propose, African lungfish is not a real fish, it is breathed with lungs, this I want to popularize this knowledge, in Africa there is a fish called lungfish, this fish in addition to being able to breathe with fish gills, may also breathe with fish swim bladders. Due to the local special climate, every once in a while it will enter a dry period, when the water of the river will dry up, and the lungfish that were originally in the water will rely on the oxygen in the swim bladder to breathe. At the same time, they hide themselves in the mud and go into hibernation. This is the real function of the evolution of fish to adapt to the local environment. That is to say, the lungfish does not have a real lungfish, because it leaves the water, the mouth is also closed, leaving the water for a long time will not die, just like the lungs, so people call it lungfish. It seems that there is no way to distinguish the species of organisms according to the text alone.
Mermaid relationship
Diagram of the Evolutionary Tree
According to the research of relevant scientists, human beings are evolved by ancient apes after three or four million years of evolution, so how did ancient apes come from? At present, the more recognized evolutionary trees roughly believe that our mammals come from reptiles, and the ancestors of reptiles are amphibians, and amphibians are all from marine aquatic animals and fish. So, humans actually evolved from ancient fish. This aspect of the data has been very my scientists have been demonstrated, we listen to it, you can also discuss it in the discussion board, because of the space limitations, we talk about the main points, can not always be entangled here.
Fish breeding methods
A diagram of how fish reproduce
Fish reproduce in three ways, namely oviparous, oviparous and viviparous. Oviparous is when a female lays mature eggs into water and fertilizes in the water to reproduce. Oviparous fish, the female fish can not protect the eggs, so the proportion of development and survival is very small. As a result of long-term evolution, the spawning volume of oviparous fish is considerable. Some spawns do not lay much eggs, such as tilapia, but the females hold the eggs in their mouths to hatch, which also ensures the continuation of offspring. Including grass carp, goldfish, salmon and other species, the female will release pheromones to lure the male fish when spawning, the male fish will hit the female's abdomen to promote ovulation, and after ovulation, the male fish will fertilize on the egg.
Egg birth is when an egg is fertilized in the female and develops in the female's reproductive tract, with nutrition still provided by the egg itself, just as a chick hatches in an egg. The "egg" is safer in the female than in vitro and can better protect the offspring. The main fish that breed in this way are turtles, sea crucian carp, mosquito-eating fish, swordtails, cranefish and most sharks. Males fertilize the female and begin spawning when her fetal spots become larger, darker, and her anus protrudes.
Viviparous, including moonlight fish, dufar and other species, fertilized eggs develop in the mother's body.
Nature's magic
A picture of a ghostly workmanship
One species of fish is a professional sharpshooter, which is the water shooter, which lives in some mangroves on the coast of the Indian and Pacific Oceans. On the surface, these small fish are nothing special, but the most amazing thing about them is that they can spew out a stream of water from the water, directly shoot some small insects that stay on the surface of the water into the water, and then eat these small insects as their own meal.
Picture of a shooting fish
There is a fish called lungfish, and in some parts of Africa the dry season lasts for several months, which forces lungfish to need to complete their survival in another way, changing themselves into cocoons.
Lungfish diagram
African lungfish hid underground for several years without eating or drinking. African lungfish face severe droughts, usually lasting several months. When the lungfish perceives that the water in the river or field is gradually drying up, the lungfish will make a hole in the mouth of the next few days and drill into it. At this time, the lungfish will secrete a large amount of mucus, which can help the soil to complete the agglomeration, and it can seal the hole, leaving only the mouth of the lungfish outside.
There is a fish called desert fish, its name is derived from its life in the desert, the world only in the United States [Death Valley] has this fish, Death Valley is located in North America at the lowest altitude, the hottest temperature, the driest place on the surface, its living environment is extremely harsh, only a few creatures can survive, such as rattlesnakes and geckos. But because desert fish are fish after all, they also need water, and there is a small puddle at the bottom of Death Valley, and such a little space has given birth to a life that has survived for up to 50,000 years. Because of their poor survival and extreme lack of food, they are said to have evolved to survive for several years without eating or drinking.
Desert Fish Map
Fish transmission routes
The first pathway is that the soil contains fish roe when the soil encounters water and has corresponding suitable temperature conditions. The roe will naturally hatch and become juveniles.
The second way is the wind of nature, the fish eggs are laid in the algae, the water surface gradually falls, in a rainy and windy weather, the algae is not likely to blow away, scattered to a certain body of water, when the environment is suitable for hatching into fish.
Birds and fish
The third way is the animals flying in the sky, some go to the water's edge to drink water, some want to catch small fish, their feathers may be stained with water, there are fish eggs in the water, birds fly around, because of chance, they come to a certain body of water.
The fourth way is that turtles crawl around, frogs jump around, small green snakes shuttle between land and water bodies, crabs run rampant, dragonfly larvae become dragonflies, in short, these animals are stained with fish eggs, they also follow the old saying, often walk by the river, where there are shoes that are not wet. It is these "shoes" with fish eggs that help the fish "migrate".
The fifth way is humans, humans have to water fruit trees or crops, humans may also have been active between different bodies of water, humans themselves, or the equipment used with fish eggs, these will help fish "migrate", at that time there were also a few people like to release some aquatic animals, these are "helping the fish" migration.
The sixth way is the fish themselves, fish like to swim up against the current, heavy rain, rainwater from the mountains into the river, the fish may swim against the current to a certain body of water.
The seventh way, the eighth way, the N way are all possible, please leave a message in the discussion area, many ways waiting to be excavated.
summary
Speaking of this, everyone can clearly understand that there is water and fish are relative, and fish cannot be made out of nothing. Of course, there will be a lot of mysteries that cannot be solved, welcome to leave a message in the comment area, share their feelings together, and also welcome the small partners to move the Yang finger of fortune to pay attention to, collect, forward, solve the doubts in the heart, share the interesting things around us, our slogan is to produce happiness and spread science.