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Find an evolution of snakes to tell you, it's not that you need it or not, it's a matter of species evolution. On February 20, 2006, according to foreign news, Australian scientists found that this snake evolved from a lizard by studying the fossil of a giant snake bone 30 million years ago, which is of great significance for the study of the evolutionary history of reptiles. The earliest ancestors of reptiles may have been lizards, but ironically, as descendants of lizards, the snake family usually feeds on lizards.
Recently, scientists discovered a well-preserved fossilized snake bone near Mount Yaisa in Brisbane, Australia, which is about 18 feet long, and its characteristics have been described in detail in the prestigious journal Nature. Scientists named it "Sky Snake", the term ** from the Australian Aborigines, in some myths and legends the aborigines blame the occurrence of natural disasters such as floods on the "Sky Snake", which is closely related to the rainbow in the sky. Because giant snake bones are fragile and difficult to preserve intact, the origin of snakes has been a question for scientists for a long time, and Jack Garron, a paleontologist at the University of Queensland, believes that the discovery of this complete snake bone will help scientists understand the evolution of snakes from lizards and how they evolved.
The snake family has existed in the ancient Mediterranean Sea (now Australia, Antarctica, Africa and South America) since the time of the Gondwana continent, and has been around for tens of millions of years. They also found a giant fossilized snake bone that had been badly damaged and deformed, which is speculated to predate the appearance of the "celestial snake". Scientists point out that snakes in ancient times had relatively strong and inflexible throats, unlike modern snakes, which had a very loose throat structure and could swallow animals several times larger than their bodies with their mouths wide open.
Queensland, Australia, is home to many fossils of ancient ancestors of modern animals such as kangaroos, wombats, crocodiles and bats. Paleontologist Peter Roberie of the California Academy of Natural Sciences in San Francisco, USA, praised Garron's discovery as a bridge between the known lizards and a family of snakes that went extinct long ago. The discovery of this fossil could also help to understand the evolutionary history of modern snakes, as their skeletal structures are many similar to those of lizards.
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Snakes originally had no legs and feet, and they didn't need legs and feet, long-term evolution is like this, and it's not a snake if it's added.
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Add leg and foot ......Just think about geckos. I don't think he needs ......After all, it was nature's choice to evolve in this way.
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The four-legged snake crawling on a person means that a lizard has crawled on a person.
Four-legged snake"Commonly known as lizard and skink because it has"Snakes"In fact, the four-legged snake is neither a snake nor a bite. The four-legged snake is about 20 centimeters long, and its tail is extremely long, accounting for about 2 3 of the total length. The whole is covered with scales.
snout obtuse rounded, snout length times the diameter of the eye; Nostrils in the scales of the nose**; 2 3 small scales between the nasal scales, snout scales, and the first upper lip scale; head scales vary in size and are all ridged; There is a tympanic membrane, which is covered with small scales; The eyelids are well-developed and motile, and the pupils are rounded. dorsal scales and lateral scales smaller; There are hyenas on the back, which become smaller and smaller the backward until the tail disappears; It has 1 row of scales on each of its two outer sides.
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It's not interesting, it's just just climbing up.
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Serpents have no legs. Its body bones do not have limbs, and it is a reptile with vestigial limbs.
The internal structure of the snake is divided into ten parts: ** system, skeletal system, muscle system, respiratory system, digestive system, cloaca system, nervous system, sensory organs and chromosomes.
The snake is able to crawl because it has a special way of locomotion:
One is the meandering movement, in which all snakes are able to crawl forward. When crawling, the snake body makes a horizontal wavy bend on the ground, so that the back of the bend exerts force on the rough ground, and the reaction force of the ground pushes the snake body forward, if the snake is placed on a smooth glass plate, then it will be difficult to move an inch, and it will not be able to crawl in this way, of course, there is no need to worry about the snake, because in nature there will be no smooth ground like glass.
The second is the crawler movement, the snake does not have a sternum, its ribs can move freely back and forth, and there are costal skin muscles between the ribs and the abdominal scales. When the costal muscles contract, the ribs move forward, which drives the wide abdominal scales to erect in turn, that is, slightly warped, the upturned abdominal scales are like stepping on the ground, but at this time only the abdominal scales move and the snake body does not move, and then the costal skin muscles relax, the posterior edge of the abdominal scales exert force on the rough ground, and push the snake body forward by reaction, and the effect of this movement is to make the snake body crawl forward in a straight line, just like a tank.
The third way is the telescopic movement, the front of the snake body is raised, stretch forward as much as possible, when it touches the supported object, the back of the snake will follow the retraction forward, and then lift the front of the body to stretch forward to get the support, and the back part will retract forward, so that the snake can continue to crawl forward. Snakes that crawl slowly on the ground, such as lead-colored water snakes, will quickly expand and contract continuously when alarmed, speeding up the crawling speed and giving people the feeling of jumping.
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Pythons have no feet, at the back of the python's body, the protrusions are called stump feet, in the process of evolution, snakes initially had feet, with evolution, snake's feet gradually disappeared, snakes no longer move with feet, but use the scales on the body, as well as the flexion and extension of muscles to crawl.
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Snakes have no feet. The snake crawls by using the twisting and swinging of the snake's abdominal scales and body muscles.
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The average snake has no legs, but there is an animal called the "four-legged snake" in the world, which has four legs, similar in appearance to the brachied tiger, but larger than the brachied tiger, and generally lives in the southwest of China
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Snakes have legs, just less obviously. It's just that in the process of evolution, the snake gradually shifted from the ground to the ground, because it is very inconvenient to have four legs in the ground (mainly the size of the hole, because the snake's food is animals about the same size as the diameter of its body). So the snake's feet slowly degenerate, and in the end they are only about five millimeters (if you look closely).
But some snakes are still undegenerate, and still have legs as long as lizards.
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Snakes should belong to the legless reptiles, excluding some snake evolutionary base mutant foot species.
The snake has no feet, and the snake is called a drawing snake to add enough proof.
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No, it moves on its belly, but snakes used to be in mythology
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Snakes have legs, and in the snake skin, they are usually not visible, but I saw them when I was a child, and my uncle killed the snake, and after removing the skin from many layers, you can see it, as well as toes and nails.
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Snakes are said to have legs, and you can try roasting a snake over a fire so that its feet stick out. Its feet are small, though.
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Some have, but very, very few. Probably gone, most of them not.
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Legend has it, reality doesn't know.
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