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Recently, a Hollywood blockbuster "Megalodon" was screened, which made many people see the horror of the marine monster. In fact, in prehistoric times, there were still many maritime overlords who stood at the top of the food chain, and the three giant beasts brought today are part of them, and they ruled the underwater world for a period of time.
First, strange shrimp
Looking back at history, when it comes to giant beasts, we have to mention the Cambrian odd shrimp, although they are only about 1 meter long, it seems to have nothing to do with the word "giant beast", but during that period, it was indeed a real giant predator.
In addition, don't look at the word shrimp in its name, just think it's the same as the shrimp we are familiar with now. This guy is a genus of odd shrimp in the family Odd Shrimp, and is considered a close relative of the arthropod phylum.
It is a flat, free-swimming animal with a concrete joint structure that can use soft appendages on both sides of the body to make wavy movements in the water, and the appendages overlap on both sides of the body to form a single "fan" to help the body move in the water.
The widest part of the body is located between the third and fifth pairs of appendages, the closer you get to the tail, the narrower it becomes, and you have at least 11 pairs of appendages. The appendages closer to the caudal end are difficult to distinguish, so the number of appendages is difficult to calculate.
This big eye is still a bit cute
Odd shrimp have a pair of eyes (compound eyes) that are 3 cm long and are estimated to have as many as 16,000 crystals. Up to now, only dragonflies (with 28,000 crystals) can compare with it.
In the Cambrian period, the compound eyes of trilobites only had the ability to distinguish between day and night, and the compound eyes of odd shrimp were thirty times more acute than those of trilobites, and they also used this advantage to firmly control the initiative.
The front of the mouth of the odd shrimp has two appendages that resemble the tail of the shrimp, which can be opened up to seven feet. The structure of the mouth of the odd shrimp is very unique, consisting of 32 overlapping tooth plates, including 4 large tooth plates and 32 small tooth plates, shaped like pineapple slices, with a ring of hard and sharp teeth in the center.
Its mouth is more rectangular than round, and the ring of teeth cannot touch each other. Nevertheless, it still has the ability to bite open the shells of small arthropods such as trilobites, as well as other animals.
Odd shrimp have a large fan-shaped tail that can make wavy movements with the appendages, and it is likely that it can push the odd shrimp forward in the water.
It is widely distributed in the Cambrian oceans, and can be found all over the world, including China, Canada, Utah and Australia, and survived from the early to mid Cambrian period.
Odd shrimp feed mainly on hard-shelled organisms, including trilobites. Odd shrimp have a strong mouth structure that can penetrate the shells of shellfish, showing that they are a predator.
2. Spiny tooth shark
When it comes to sharks, I believe that the shadow brought by the "Megalodon" movie has not yet dissipated, and the megalodon shark in the film is about 15 meters in size, and the maximum can reach 19 meters - 20 meters, which has been called the largest shark.
Although the spiny tooth shark we are going to talk about now has a shark word and a body length of 15 meters, it does not belong to sharks, it is an ancient fish, cartilaginous fish, plate gill subclass, spinodon shark order.
This 270 million-year-old ancient fish was also dominated for a while, its English name is Helicoprion, Helico is derived from the Greek word "spiral", and Prion is derived from "saw", which together means "spiral saw".
Megalodon + Chainsaw horror visual sense
This also fits its image, unlike the powerful bite force of the megalodon shark, it does not even have upper teeth to complete the bite, only the spiral fangs that keep erupting grow on the jaw.
These teeth, from large to small, are rolled into a circular spiral tooth, like a milling cutter, extremely cutting, and look chilling.
Regarding how to eat, scientists said that in fact, the spiny tooth shark will still use the bite action, because the jaw is too narrow to suck and eat, so it can only rely on the saw-like jaw to cut the prey, and at the same time bite is also feeding food into the mouth.
Their structure has led to the abandonment of prey with thick carapaces and the need to focus on dishes that are relatively "soft", such as the ancestors of squid and octopus, prehistoric cephalopods.
Third, the dragon
Canglong was the largest top predator in the Mesozoic ocean, although its evolutionary history was short, evolved from the cliff lizard on land, but once the climate drove out many dragons, it was also a marine amphibian that breathed with its lungs, and it was also a fetal germ.
In addition, Canglong is only a genus of the Family Ofonidae, and there are currently 27 species known: Astral VertebrateOsaurus, Canglong, Floating Dragon, Ocean Dragon, Neptune Dragon and so on.
The body shape of the dragons resembled that of modern monitor lizards, but in order to adapt to swimming, the body became more slender, with a medium-sized head, a short and thick neck, a tail equal to the length of the body, a reduced length of limb bones, and their fin-like limbs formed by webbing between slender phalanges. Their tails are wide and provide strength when moving.
They may have moved in a manner similar to today's moray eels or sea snakes. The body is snake-like and twisted during movement. The limbs are fin-shaped and play a helmsmanship role. The anterior and posterior feet are multi-toed segments. Up to 10 toe nodes are more. The teeth are tapered, large and sharp.
The teeth of the dragon are sharp and conical, curved in the shape of a barb, the jaws produce a huge twist while biting to break the prey, and there is a ring of inner teeth inside the upper jaw for dragging food. It eats in a manner similar to that of modern Komodo dragons.
Remember its domineering appearance in Jurassic Park?
In terms of vision, the eye is almost a decoration, and it mainly relies on a developed sense of smell and hearing. Like its ancestors, the main sniffing organ is still the tongue, and their ears can amplify sound even 38 times.
The smallest known species of plesiosaurs is Carinodens belgicus, which is 3 to 3.5 m long and probably lives in shallow seas along the shore, using its bulbous teeth to catch mollusks and sea urchins for food. The larger dragons are more typical: the dragons can reach a length of up to 17 meters. Helenosaurus is the longest species of diplodocus , measuring 17.5 m long.
For hundreds of millions of years, the earth has been that earth, and the once vicious beasts have turned into fossils, but their legends have not been annihilated. With the advent of human beings, although the land has undergone earth-shaking changes, the sea world has preserved many traces of history.
Human beings are also in the continuous exploration to understand the true face of the earth, the rise of diving let us into a new field, explore the unknown world and feel the magic of nature has become the core charm of the sport of diving!
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