Majestic and spectacular, the Himalayas are the highest mountain in the world. Very few people can successfully reach the top, so no one will believe that they can find a "fish" in this place. Because of the extremely high altitude, extremely low temperature, and perennial snow and ice cover, there are not many animals and plants on the mountain, especially reptiles, but 200 million years ago, animals landed here. And it's all over the world, and it's a marine reptile, so is it swimming up the Himalayas?
This mysterious animal is the Ichthyosaur.
< h1 class= "pgc-h-arrow-right" > the mountaineering team found fossils</h1>
In 1964, China's mountaineering team found ichthyosaur fossils in the Himalayas, this place is 4300 meters above sea level, even if the climbing team members stand here, they will still feel cold and intolerable, lack of oxygen, it is difficult to believe that ichthyosaurs once lived in such a place.
Therefore, since 1966, China has organized many biological expeditions to the Himalayas, and new fossils have been discovered continuously during the investigation, which still contains many fossils similar to ichthyosaurs, but they are not very certain, because for the sake of rigor, these fossils were quickly transported back to the institute and handed over to the corresponding experts to study. After research, biologists believe that these fossils do belong to ichthyosaurs, and are a new genus in the ichthyosaur family, and named them Tibetan Himalayan ichthyosaurs. From the appearance point of view, this ichthyosaur is very similar to today's sharks, the body length is about 10 meters, they have sharp teeth in their mouths, and the teeth are flattened and cone-shaped; The eyes are very large and round, suitable for living in the deep sea area; The entire head is triangular; The limbs have evolved into flipper-footed, flattened, suitable for swimming: the body is spindle-shaped, the tail is long and powerful, and the tail of the ichthyosaur will provide it with assistance during its swimming, which makes the ichthyosaur one of the fastest swimming creatures in the ocean, which is also one of its advantages in the marine world.
The Himalayas are snow-capped, with protruding peaks and endless horizons, known as the roof of the world, full of glacial snowflakes, and in such a place, so many ichthyosaur fossils can be found, and the investigators are really surprised. How did the ichthyosaur, which originally lived in the deep ocean, come to the Himalayas? Is it really a swim up? To figure this out, biologists and expeditions have studied this in depth...
<h1 class= "pgc-h-arrow-right" > restore the former overlord and lament the vicissitudes of the sea</h1>
After investigation, it was found that 180 million years ago, the Himalayas were still a vast ocean, vast and turbulent, and fish and dragons lived in it. However, due to earthquakes or volcanic eruptions caused by frequent crustal movement, the earth's crust rises year by year, and with the passage of time, the sea becomes a mulberry field and becomes a mountain, and the Himalayas are still increasing at a certain rate every year. In the process, the ichthyosaurs that originally lived in the sea could not escape, so they were buried in the dirt and became fossils in time.
From the fossil point of view, the ichthyosaur tail vertebrae folded downward into the lower lobe of the tail fin, at first biologists thought that the tail of the ichthyosaur was injured, but later found out that this is a special structure of the ichthyosaur in the evolutionary process, and with evolution, the degree of downward folding will deepen. In the early days, this degree of down-folding will be lighter, or even invisible, but in the late period, the degree of down-folding is very strong, making people feel as if the tail has been greatly damaged, and in the end, the upper and lower lobes of the tail fin are almost the same, this evolutionary way makes the tail fin like a rock when swimming in the water, which can speed up the swimming speed of the ichthyosaur. Based on these characteristics, biologists deduce that the fossils should have been produced in the Late Triassic, when it was still a vast ocean that could communicate with the ancient Mediterranean Sea, so the ichthyosaur did not really "swim" up, but because the crustal movement was buried in the soil, the crust rose, and it took tens of millions of years to reach its current position.
<h1 class="pgc-h-arrow-right" > dolphin-like fertility patterns</h1>
In the Late Triassic period, reptiles were abundant, and in addition to ichthyosaurs, most snake dinosaurs, turtles, lizards, etc. belonged to reptiles. Reptiles are generally oviparous, and during the breeding season, reptiles will crawl to land to lay their eggs and then hatch into pups on land, such as turtles. Biologists wonder if this is the case with Ichthyosaurs.
Later, when paleontologists studied ichthyosaur fossils, they found that some of them were pregnant, proving that ichthyosaurs, like whales and dolphins, could not spawn on land, but directly gave birth to small ichthyosaurs. Biologists believe that the fossil of an ichthyosaur in a pregnant state can be divided into two possibilities, one is normal reproduction, the small ichthyosaur lives well, and the tail will come out; The second is that the ichthyosaur is dead, and as the ichthyosaur's body continues to decay, it will produce the corresponding gas, pushing the small ichthyosaur out of the birth canal, and the small ichthyosaur is born. This mode of production is common in whales.
Why do you say that Mr. Will out of the tail?
This is because if mr. head comes out, the little ichthyosaur is likely to drown in the water, and this situation will also involve the ichthyosaur and die. When the small ichthyosaur dies, it will remain in the cloaca, the activity of the ichthyosaur will be blocked, and the body of the small ichthyosaur will continue to decay, producing toxic substances, and the ichthyosaur will also be poisoned. Only Mr. Tail can survive. Of course, biologists also found in the investigation that there are also Mr. Head who have survived, such as such as dolphins, but successful cases are rare.
Who knows what the once overlords became, what was once the oceans became land and ridges, the world has been changing, and what will become in the future?