When the tide is about to come in the sandy sand of the beach, there are many jumping fish, there are two feet like frogs, obviously they are a fish, but they have long legs and still jump on the beach, which is very strange. Today's topic starts with this kind of walking fish. The so-called jumping fish is also called mudskipper, this kind of mudskipper has not liked to stay in the water, most of their lives on land, what shoals, swamps, intertidal zone are suitable for landing, similar to frogs and salamanders these amphibians.
Will the mudskipper, although it looks like a fish, actually be an amphibian like a baby fish?
This is to say about the origin of the mudskipper, the mudskipper is the goby family, in the biological classification belongs to the chordate phylum - radial finfish - gobies - mudskipper genus, is an authentic fish, not an amphibian.
Morphologically speaking, the mudskipper is very close to the gobies, including two distinct features, one is that the eyes are protruding above the head, and the field of view is very wide. The other is the shape of the abdominal fin fused into a suction cup, which is like a flat support to prop up the upper body, and the expressions of the two people are also very similar, they are not very smart feelings, and they are a family at a glance. Then as a fish that is not very serious and wants to live on land, you must face two basic problems, one is the breathing problem, after coming out of the water, the gills' ventilation efficiency must be greatly reduced, you have to have other ways to do it, the other is how to move the problem, without the buoyancy of the water you have to face the gravity of the earth, cetaceans stranded and clumsy seals and sea lions after landing is a good example, indicating that the parallel goods will not be very easy after landing.
How do mudskippers solve the problem of breathing and moving?
First of all, the breathing problem, mudskippers come to land, more than a few functions. One is more through the function of breathing through the skin, which is the same as the frog, the lung function of the frog is not enough to rely on the skin to help, not only with the skin to breathe, there is a premise is to keep wet, dry is not smooth, so you will often see mudskippers rolling on the mud, at every turn inexplicably lie down, this is to ensure smooth breathing to do so. In addition, the gills of the mudskipper are particularly large, it can contain a particularly large mouthful of water in the mouth, as a reserve water for gill breathing, and after the oxygen in the saliva is consumed, the mudskipper will find a puddle to replace it with a mouthful of water, that is to say, even if it is on the shore, its gills are still working, this operation is a bit like what, a bit like the feeling of free diving without an oxygen cylinder, sucking in a full breath before going into the water, holding on for a while, you have to come up to change your breath. Mudskippers are equivalent to reverse operations, we dive in water, they dive in air, probably this meaning. Then in addition to the skin and gills, the inner wall of the mouth and throat of the mudskipper can also be exchanged for gas, but the premise must also be moist, and no matter which way the mudskipper breathes, it is still inseparable from the water for the time being, although the mouth says that it likes land life, but the body is still very honest. At this stage, they can only live in the semi-wet and semi-dry mudflats, so there are also called beach fish that are also very intimate, so that the problem of breathing is solved, and the problem of walking should be solved.
How do mudskippers walk when they reach shore?
If it is just like the killer whale on the beach, twisting around on the beach is obviously a little bit not enough to see, like a seal jumping on the belly and walking with the belly also feels not flexible enough, so at least you have to use the pectoral fin and tail fin like a sea lion to say that you can walk, people mudskippers really do this, saying that the mudskipper's pectoral fin is very developed, which is the result of leaving the buoyancy of the water to re-adapt to the gravity of the earth, after all, doing flat support on the ground is much more difficult than the goby in the water, and it is not enough to have developed muscles. A pair of pectoral fins of the mudskipper are obviously much longer, and even evolved a joint suitable for walking, both the elbow joint and the shoulder joint, you can make a forward crawling action without any sense of violation, and then with the parafin in the middle of the pectoral fin, the iconic crutch walking method of the mudskipper is so formed, why is it called the walking cane walking method, because the logic of its walking is exactly the same as the person who walks on the double crutches, the anabrasive fin in the middle, the pectoral fin to take a step forward, and then the parafin to support the pectoral fin and take another step, It's still pretty fast if you've been feeding it all the time, so you can move very quickly on land, which is very important for them to prey on and avoid danger. In addition, mudskippers will also suck their parafins on rock walls or tree trunks so that they can complete the climbing action by taking one step at a time, so it is quite remarkable that mudskippers are not only walking fish but also tree-climbing fish. Then in addition to the main abduction walking, the bouncing power of the mudskipper is also amazing, often jumping around in the mud, which is the origin of the two names of the mudskipper and the jumping fish, then the mudskipper jump is not dependent on the pair of pectoral fins, this has to rely on their tails, the mudskipper arches its body and jumps up on the ground with its tail, and it can even jump out of tens of centimeters. This is very useful when they launch a surprise attack or escape, and another important role is to use it to engage in objects, male mudskippers often have many beautiful spots on the dorsal fin, the courtship season is particularly bright, some dorsal fins open, like the wings of the dragon quite imposing, and their throats will become brighter and fuller. These are the characteristics they use to attract females, but living in the mud is a bit of a distraction, because it is not as easy to be noticed by females as in the water, especially the throat is completely unobtrusive, and it is all depressed. What to do, the male mudskipper thought of throwing himself into the air, showing off the dorsal fin and showing off the throat, and the higher the jump, the healthier the body, through this courtship dance to attract potential females.
Of course, sometimes, two males who fight and dance also have eyes, and a fight is inevitable. Mudskippers are exactly like this when they are dry, both of them open their mouths to the maximum, yell at each other and it is over, even if the mouths are stuck together, there is no intention of closing their mouths to bite each other. Rushing up is just to roar a little more imposingly, that's all. As for how to finally determine the victory or defeat after a crazy roar, we don't know, maybe who yells first and lacks oxygen even if who loses, in short, the winning male is easy to win the female's heart, the female will follow it to the pot it has dug in advance to complete the rest of her life, then when it comes to the hole dug by the mudskipper, there is still a lot of success inside. First of all, why should mudskippers dig a hole and live in a hole? This is also related to their dislike of living in the water, because their body structure is no longer suitable for swimming, very inflexible in the water, and the eyes are also very clear on land, it is very blurry underwater, and it is quite dangerous to talk about mudskippers staying in the water at high tide, so it is necessary to dig a hole in the beach to make a home and avoid predators at high tide. Is such a reason, but as a fish, want to dig a hole in the ground is not so easy, mudskipper is still very ambitious, although there is no industrious hands but people have a diligent mouth, go in and nibble a mouthful of mud to climb out and spit it out, and then bite and spit it out, just bite out a hole, it is too inspiring, and everyone don't think that the hole that the mudskipper chews out with its mouth is very simple, in fact, their hole is still very designed, There are vertical parts and curved parts, even if the tide is high, the hole will not be completely filled, always flow out of the livable room with air, which can also be seen that the mudskipper is really iron heart does not want to stay in the water, then when the female mudskipper spawns, it will lay the eggs in these airy rooms, and then the male fish will fertilize the eggs, and the follow-up care work is also taken care of by the male, one of the main tasks is to ensure that the oxygen in the room is sufficient, how to do it, or use the mouth. The male fish will take a full breath at the mouth of the hole and then transport it in, just like this mouthful of fresh air outside the hole to spit in the room, playing the role of a human flesh ventilation fan is very difficult, so the mouth of the mudskipper, eating, fighting, breathing, digging holes, ventilation are all dependent on it. I don't think it's an exaggeration to say that it's the most versatile mouth in the world
So how does the mudskipper come to live on land? It's easy to overlook, that is, fish don't have a tongue or they don't have a tongue like a terrestrial vertebrate, which is not a big deal if it's put in water, because when the fish eat, they suck food and water into their mouths and then filter the water out. The flow of water helps them swallow food, and if they come to land, it is troublesome to not have a tongue, which is absolutely indispensable for vertebrates on land. Then let's talk about how mudskippers eat some insects on land, small shrimp, small crabs, and organic pieces. If they have a tongue like a frog, then it is naturally excellent, it is quite difficult to suck food into the mouth out of thin air, and the mudskipper has developed a very ingenious way to achieve the function of the tongue, the mudskipper will take a mouthful of water in the mouth when eating, and after being close enough to the food, it will spit out the water to wrap the food, and then instantly and quickly suck the saliva back to eat the food by the way, even swallowing it in one go, and finally solving the problem of eating. From the above content, we can see that mudskippers have gone to great lengths to live on land, but the difference between them and terrestrial vertebrates is still obvious, and they do not walk on all fours without breathing with their lungs.