When you think of dinosaurs, you will think of the big meteorite that was 65 million years old, as if the dinosaurs were directly killed by meteorites.
With the in-depth analysis of the crater of that year, scientists found that the extinction of dinosaurs that year was far more terrifying than previously imagined.
Geological layers are a history book that can lead people back hundreds of millions of years.
The crater on Mexico's Yucatan Peninsula is the key to this history.
Meteorites hit Earth
Dinosaur Dynasty
Dinosaurs ruled the earth for almost 160 million years, a length of time that no fauna has surpassed, from the end of the Triassic to the Cretaceous, dinosaurs spanned an entire Mesozoic Era.
Many people feel sorry for the dinosaurs, if it were not for the meteorite, the earth might still be under their rule.
The secret to the longevity of dinosaur dynasties is that they occupied almost every terrestrial niche.
In terms of top carnivores, they have theropod dinosaurs, the star dinosaur Tyrannosaurus rex, and the lion tiger are not enough for it to plug its teeth.
Dinosaur Dynasty
In terms of grazing, they are more, they have Mamenxi dragon, brachiosaurus, lianglong, these height directly killed today's giraffes, weight directly crushed elephants.
In addition, there are triceratops, stegosaurs, duck-billed dragons, and armored ankylosaurs.
In short, you can think of the way the terrestrial creatures live, the dinosaurs have played it for 160 million years.
So much so that our mammalian ancestors, in the dinosaur dynasty, could only be the bottom of the food chain and only dared to come out at night.
Huge dinosaurs
Many animals today have a certain degree of color blindness, most of which can only see black and white, and even humans can not see any color.
This is actually the after-effects of our ancestors under the pressure of the dinosaurs.
Mammals' strong sense of smell and hearing is also a survival skill cultivated in the era of dinosaurs.
Mammals of the age of the dinosaurs
In general, because dinosaurs occupied almost all ecological niches in the Mesozoic Era, mammals could only become nocturnal animals.
It's really hard to imagine how mammals would have fought back without that big meteorite.
65 million years ago, a meteorite about 10 kilometers in diameter struck the Earth in what is now the Yucatan Peninsula in Mexico.
The Dinosaur Dynasty was stopped in front of this involuntary alien visitor. So what really happened back then?
Meteorites hit Earth
Meteorite of destiny
In mexico's Yucatan Peninsula, there is a crater with a diameter of 180 kilometers and a depth of 900 meters, which is not on the ground, but underground, and even a large part of the seabed.
Humans can't see the crater standing on the ground, and can only rely on satellite maps to see its real body.
Scientists took samples of rock near the crater and detected traces of iridium.
Iridium is one of the rarest elements on Earth, and iridium may only account for 0.001 parts per million in the entire crust.
Obviously, the amount of iridium in this impact crater in Mexico alone may exceed the sum of iridium in the Earth's crust.
Yucatan Peninsula, Mexico
Because these iridium elements come from outer space, the proportion of iridium in meteorites is higher, which is 500 times the content of the earth's crust.
Based on this meteorite impact crater, scientists have calculated that the energy released by the meteorite when it hits is equivalent to 100 million tons of TNT explosives and 4.5 billion "Little Boy" nuclear bombs, and on the day of the impact, the shock wave hit the entire North American continent.
But according to dinosaur fossils, the extinction of dinosaurs was not completed in a day, on the contrary, the extinction process of dinosaurs lasted tens of thousands of years.
This suggests that not all dinosaurs went extinct on the day of the impact.
The day the impact occurred
Dinosaur extinction
The moment the meteorite hits, the huge impact makes the entire crust shake, and soon there are tsunamis, earthquakes and volcanic eruptions.
Hundreds of kilometers in all directions of the impact, the forest fell into a sea of fire, and the dinosaurs fled in panic, but found that they could not escape anyway.
Because the fragments of the meteorite impact were splashed into the air and then fell, falling from the sky, a dense meteorite rain was formed.
Large dinosaurs have nowhere to hide and can only be smashed to death.
The day of the meteorite impact
Dust from the impact and ash from volcanic eruptions enveloped the entire planet, and plants fell because they could not receive sunlight.
There were no dinosaurs that died on the spot, and they couldn't survive the food shortage after that.
A large number of plant-eating dinosaurs died, followed by carnivorous dinosaurs.
Only a few small and medium-sized dinosaurs remain, struggling on the brink of extinction.
Small and medium-sized dinosaurs
The volcano erupted large amounts of sulfur dioxide, an icy chamber gas that would cause the world to cool, and a cold winter befell the earth.
In this dark and cold environment, there is less and less food, and even small and medium-sized dinosaurs cannot meet their own lives.
After tens of thousands of years, these only remaining dinosaurs have completed the last period of the dynasty.
The demise of the dynasty, naturally there will be a grand funeral, and the pterosaurs and plesiosaurs, which belong to the evolutionary branch of the main dragon class with the dinosaurs, are also all extinct, and even 5 species of mammals have not survived.
Plesiosaurs were also extinct
The meteorite-induced mass extinction is known as the late Cretaceous mass extinction, in which about 76 percent of the world's species disappeared.
This extinction also has a name - the dinosaur mass extinction.
Scientists once thought that the dinosaur family no longer existed, but we underestimated the extent to which dinosaurs occupied the ecological niche in the first place.
Pterosaurs are also extinct
The last glory of the dinosaurs
At first, scientists always thought that dinosaurs were a kind of lizard, so we will find that the early dinosaur restorations were all large lizards with scales.
However, as more and more dinosaur fossils have been unearthed, some well-preserved fossils have shown that dinosaurs have feathers.
The famous biologist Thomas Henry Huxley discovered during a chicken eating that the skeletons of birds and dinosaurs are surprisingly similar.
Huxley was a staunch advocate of Darwin's theory of evolution, and he was quick to hypothesize that birds evolved from dinosaurs.
Dinosaurs also wanted to fly into the sky
So in the following time, paleontologists tried to use fossils to connect the evolution of birds, and finally found the most critical link in northeast China - the Chinese dragon bird, and the evolutionary process of birds was clear.
Birds did not evolve from dinosaurs, they were a class of dinosaurs, and this evolutionary branch was called the Hand Robbers.
The hand-raptors belonged to the theropod suborder , small and medium-sized carnivorous dinosaurs , some of which later became vegetarian. In the early Cretaceous Period, members with gliding abilities emerged from the hand-raptors.
Based on them, the bird taxa began to differentiate from the dinosaurs.
Chinese Dragon Bird
Moreover, birds at that time had two evolutionary branches, the anti-ornithischian suborder with teeth, and the suborder of today's birds without teeth.
The latter were the birds we have today, and the former became completely extinct at the end of the Cretaceous period.
The suborder Ornithopods were initially more inclined to ground combat, and even one branch evolved into a diving bird, the Dusk Bird, the "penguin" of the Cretaceous Period.
Later, at the end of the Cretaceous period, the pterosaurs and anti-ornithopods were extinct, the sky ecological niche was completely vacant, and the current bird subclass, as the only animal with the ability to fly, naturally wanted to occupy this big rice bowl.
Extinct anti-ornithischian subclass
Unexpectedly, this occupation has continued to this day, and has completed the blossoming of water, land and air.
Dinosaurs also gradually got rid of the traditional shape of large lizards, and their restorations began to be closer to today's birds.
To show that dinosaurs were not completely extinct, the dinosaurs that became extinct at the end of the Cretaceous period are now called "non-avian dinosaurs".
Birds were born out of the theropod suborder dinosaurs, branching out and becoming one of the animal groups that flourish today.
There are more than 10,000 species of birds on Earth, more than mammals.
Birds today
Among them, the chicken hugged the thigh of the human, and the number reached 19 billion in the world, which is the largest number of birds and continues the last glory of the dinosaurs.
Rather than lamenting the fact that the dinosaur dynasty is not the same, humanity is more worried about whether we will encounter something similar to the dinosaurs in the future and be hit by meteorites.
Scientists believe that humans are more likely to "play off" themselves than to be destroyed by meteorite impacts.
We are now most likely standing at the doorstep of the sixth mass extinction, global warming, environmental pollution, and melting glaciers, and if these problems cannot be solved, it is only a matter of time before humanity is on the road to extinction.
The last glory of the dinosaurs
There is no eternity in this universe, and human beings are nothing special for the earth, when dinosaurs can be obliterated by a meteorite, and humans will also be harmed by their own operations.