in this article we will know, how dinosaurs went entint, how dinosaurs died, when dinosaurs ruled the erath, when dinosaurs died, where dinosaurs came from, how dinosaurs really looked, can dinosaurs come back,
Hello, friends! About 100 million years ago, the Earth looked different. There were no signs of humans. And there was a kingdom of terrifying animals all over the planet. Dinosaurs that were so big that they were taller than buildings. Their claws were so powerful that they could break your bones in a second. And their speed was so fast that they ran at a speed of almost 90 km per hour. To be precise, they were heart-wrenching creatures. They ruled the Earth for more than 170 million years. But then one day, there was an incident where they suddenly disappeared from the Earth. What exactly happened? And how? Let's understand in today's article.
The word Dinosaur actually originated from Greek, friends. It is derived from the words Deinios and Sauros. Denios means Terrible. Saurus means Lizard. A terrible lizard. Literally, this is what the word Dinosaur means. It was only used for the first time in 1841. Because it was the time when the first dinosaur fossil was found. A British scientist named Richard Owen started using the word dinosaur. At that time, people didn't know much about what dinosaurs were and how they looked. So the drawings that were made in the beginning on how dinosaurs looked, looked quite different compared to today. Megalosaurus was one of the first fossils of dinosaurs to be found. After many decades, as such researchers came to know more about them, they modified their drawings, and tried to make them more realistic.
And today's depictions are something like this. Today, more than 10,000 dinosaur fossils have been excavated by paleontologists around the world, of which we have identified 900 different species of dinosaurs. You might think, how much more can we dig to discover new things? But interestingly, from 2003 onwards, By 2022, on average, every year, 45 new species of dinosaurs are found. So the work of paleontologists is still ongoing. Look at these photos of the new species of dinosaurs discovered let's start the story from the beginning.
Let's go back in time. Many millions of years back. Scientists estimate that the first dinosaur must have emerged around 230-240 million years ago. Because the oldest dinosaur fossil we have found is 231.4 million years old. was found in Africa. The condition of the Earth at that time compared to today, was very different. The continents you see today, Asia, Africa, Australia, Europe, all these continents were connected at that time. There was only one supercontinent, which we named Pangea. Scientists estimate that Pangea looked something like this. You can see where the different continents of today were. At this time, the Earth's climate was very dry, dry and arid, and there was very little rain. This time period is known as the Triassic period. A period when dinosaurs began to emerge.
Dinosaurs slowly began to come to Earth through evolution. The dinosaurs that came at this time were not as small as you imagine. They were very small in size. The most common dinosaurs at this time, were usually only 2 meters in size. For example, the Eoraptor. It's a dinosaur that existed at that time. In fact, this dinosaur is also known as the ancestor of all other dinosaurs. The dominant animals on Earth at this time were actually large reptiles. Some of these reptiles looked cute, like this one, known as the ancestor of all turtles. As time went on, the Earth began to change gradually. About 201 million years ago, the Triassic period ended. When the climate of the Earth suddenly changed, the Pangaea began to break into pieces.
When I'm using the word suddenly, it doesn't mean that it happened in a day. I'm using the word relatively. If we're looking at the time scale of millions of years, it happened gradually in a few thousands of years. Cracks started to form on the supercontinent. Large volcanic explosions occurred in these cracks. Many volcano eruptions caused the release of carbon dioxide. Sulfur dioxide was released. This caused intense global warming. The sulfur dioxide and aerosols that were found in the atmosphere, blocked the sunlight and caused cooling. Ocean acidification occurred when the carbon and sulfur dioxide were found in the water. The acidity of the water in the ocean increased. What happened was that the climate changed rapidly. And it became difficult for the animals that existed at that time to survive.
Most of the reptiles and other species were cold-blooded animals at that time. They couldn't tolerate temperature changes. But the dinosaurs were warm-blooded, like humans. It was easy to tolerate temperature changes for the dinosaurs. For nearly 6 lakh years, the volcanic eruptions continued and the climate changed. Because of this, almost all other species went extinct. The only survivors were dinosaurs, crocodiles, turtles, and early mammals. This event is known as the Triassic-Jurassic Extinction Event. And as I said, after this, the Triassic period ends and the Jurassic period begins. If you've heard of this name, then yes, friends, it's the same name used by the Jurassic Park films. They took the word Jurassic from this Jurassic period. So this Jurassic period goes on for 201 million years, up to 145 million years.
During this time, the dinosaurs are the most dominant species on Earth. Some of the earliest Titanosaurus, which were around 160 million years old, each weighed 15,000 kg. And could be up to 15 meters in length. Some other iconic dinosaurs at this time were Brontosaurus, Brachiosaurus, Diplodocus, and Stegosaurus. In this Jurassic period, flying dinosaurs also entered. The first feathered dinosaur was Archaeopteryx, which looked something like this. At the same time, our Pangaea supercontinent had expanded into two parts. Two small supercontinents. Which we named Laurasia and Gondwanaland. Because of the Jurassic Park films, the Jurassic period is best known. But in reality, the next period after it, was the period where the dinosaurs had a good time. The Cretaceous period. Because this was the time when we saw explosions in the diversity of dinosaurs.
Many new types of dinosaurs, started coming here. The T-Rex, the most famous dinosaur shown in films, actually existed in the Cretaceous Period. It reached its dominance at the end of the Cretaceous Period. From 65 million years ago to 68 million years ago. Although this is a controversial issue among researchers, most scientists believe that the T-Rex didn't actually exist in the Jurassic Period. It's ironic that a Jurassic Park film was made, and the T-Rex is shown here on its logo. The Cretaceous period was actually the longest period in the dinosaurs' era. It started 145 million years ago and lasted until 65 million years ago. The two supercontinents, Laurasia and Gondwanaland, also began to break up. And the structure of the continents started to look like today.
Many flowering plants were also born at this time. The temperature of the Earth was also very hot compared to previous periods. The sea levels were high. And almost all kinds of dinosaurs that you can imagine, exist today. Raptors, Armoured Dinosaurs, Large Herbivorous Dinosaurs, Large Carnivorous Dinosaurs, Titanosaurs, one of the largest land animals, Argentinosaurus, which could weigh up to 77 tons, and T-Rex, which was 40 feet long, and was known as the Apex Predator of its time. If you compare its claws with the most powerful animals. A fun fact here is that grass, the evolution of grass started only 70 million years ago. So in all the stories that I was about to tell you, don't imagine that grass was growing on Earth. There were other types of plants.
And T. rex and Triceratops, their evolution started 68 million years ago. Do you understand what I mean? The T. rex dinosaur, Today, we are closer to it as compared to the T-Rex dinosaur from the Jurassic period. Because there's a difference of 80 million years between the Jurassic period and the T-Rex. And between us and the T-Rex, there's only a difference of 68 million years. Another interesting dinosaur that existed at the time, the Ornithomimids. They looked like ostriches and were among the fastest dinosaurs. They could run at a speed of 80 kmph. And if we talk about flying instead of running, the largest flying dinosaur, the Quetzalcoatlus, It had a wingspan of 10-11 meters. As you can see, the period for dinosaurs was the best.
The climate was favouring them, new species were evolving, and there were no other animal species that could compete with them. So they were easily ruling the Earth. Everything was going well, until one day, something happened that would destroy dinosaurs forever. A huge asteroid, whose size was roughly 10-15 km. It flew rapidly towards the Earth and collided with the Earth. This happened about 66 million years ago. And this asteroid strike ended the Cretaceous Period. The speed of this asteroid was 30 km per second. That is 150 times faster than a jet airliner. Specifically, it collides with the Yucatan Peninsula of Mexico. This is the place where after millions of years, the Mayan tribes come up, and create historical wonders like Chichen Itza. I had explored the Yucatan Peninsula in my vlogs.
If you want, you can watch the vlogs there. I'll put the link in the description below. So what happens when an asteroid collides with this place? It forms a big pit. In a diameter of 180 km. Due to its impact, energy is released at a speed of 100 teratons TNT. Or if you compare it with the atomic bombs dropped on Hiroshima and Nagasaki, it has 1 billion times more energy than those atomic bombs. It is such a huge explosion that everything around it disappears in a blink of an eye. Due to the impact, a lot of soil floats in the air, the ground gets very hot, and this hot dust actually pours like rain on the rest of the area. The temperature on the entire Earth rises for several hours, several degrees Celsius.
The animals living in the thousands of km range of this area, are burned alive by this heat. It is believed that only small animals survived the impact of this initial blast, because they found an underground shelter, or went into the water to hide. or into caves, or into large tree trunks. This was just the initial impact. After this, there's a shockwave, a heat pulse. Wildfires are seen in the jungles for thousands of kilometers. Large tsunamis are seen. It's immediately said that a 2 km high tsunami must have occurred. Can you imagine a 2 km high tsunami? Volcanic eruptions are seen again. Acid rain falls, and earthquakes occur. These short-term effects are very dangerous. But you'd think that on the other side of the Earth, where there's an impact, some animals would have been able to survive.
But the long-term consequences are even more dangerous. The dust particles in the air block the sunlight from the Earth for the next year. A nuclear winter occurs on the planet. The temperature drops rapidly. It is estimated that for the next 3 years, freezing temperatures on Earth, causing the deaths of many plants and animals. And because sunlight was blocked for a year, photosynthesis became impossible for plants. So plants die, and plants die, and herbivores die. And because of that, the carnivores die. There's a chain reaction here. The only animals that survived the consequences, were the small omnivorous animals. Like mammals, crickets, turtles, and some birds. These animals are able to survive because they can survive like scavengers. The dead dinosaurs, some fungus growing on the ground, the decaying plant matter, are eaten by them.
Small animals can survive for a long time. The impact of the asteroid had destroyed many carbonate rocks. Due to which, carbon and sulphur go back into the atmosphere. And for the next thousands of years, the sunlight is quite reduced. It's not in the normal amount. Apart from this, acid rain continues for thousands of years. When the nuclear winter ends, the dust in the atmosphere settles down. The sunlight comes back to the planet. But the problem is that a lot of carbon dioxide has been released in the atmosphere. Because of this, we get to see intense global warming. Think about it, friends. One asteroid changed the history of the Earth for thousands of years. If we ignore some exceptions, even a four-legged creature, weighing more than 25 kg, could not survive this event.
All the terrestrial dinosaurs were extinct. Along with them, all the plant and animal species living on Earth, were more than 75% extinct. At this point, the Cretaceous Period ends. is the beginning of the next era, which we call the Paleogene Period. It's not as if everything is over. This event comes as an opportunity for the remaining species of animals. The kings of the earth, the dinosaurs, are no more. So for the rest of the animals, this is an opportunity to rise. To rule the earth. Humans should thank this asteroid first, because the mammals got a good chance of evolution after the dinosaurs left. The gap that the dinosaurs left in the food chain, was filled in by many mammals. During this period, we saw the evolution of horses, whales, lizards, primates, and many snakes and small lizards emerged here.
The only group of dinosaurs that survived were actually flying dinosaurs. which evolved gradually, and became birds after evolution. You heard it right. The birds you see in the sky today, are the ancestors of the flying dinosaurs. Most studies have confirmed that birds belong to the same family as dinosaurs. Specifically, the most ancestry is shared by chickens and ostriches. This is why some people say that the T-Rex, such a dangerous dinosaur, The closest living relative today is a chicken. A chicken. You must be wondering about the asteroid. How did we find out today that the asteroid crashed there? And 66 million years ago, how did we find out about this date? There's evidence behind this, a rare mineral, called Iridium. Scientists found that on Earth, on many places, on the ground, we see a high concentration of Iridium today.
But when geologists analysed the Earth, they found that it is a very rare mineral on Earth. But it is still abundant on our ground. How is this possible? This is possible because in comets and asteroids, there is a high concentration of Iridium. When scientists studied the dating of Iridium, they found that all the Iridium that we're getting is 66 million years old. This can only happen when an asteroid collides with the Earth, and when the asteroid is completely blasted, the minerals present around it spread all over the Earth. And you might be thinking that when the asteroid has had such a huge impact, we should be able to see its pit somewhere on Earth. This is true, but something that happened 66 million years ago, might not look like what you imagine.
Because since then, continents have also kept shifting here and there. Today, the asteroid crater is hidden in the Yucatan Peninsula. But several digging expeditions have been conducted to prove that it actually happened. And that it happened at this location. If you look at the map, you'll see its exact location here. It's half in the water, half below the sea, and half below the ground. A real-world impact that can be seen today, is the cenotes in this area of Mexico. These very beautiful sinkholes, in which you can see a pattern, the crater formed by the asteroid, all these cenotes are actually seen in a ring formation around the crater. Today, it is a major tourist attraction. You can even go swimming in these cenotes.
In total, all these cenotes make up the world's largest underground cave system. Listening to the story of the asteroid strike, one thing might be coming to your mind. What would happen if an asteroid collided with the Earth today? Would humans also be destroyed completely? This is definitely a threat. The asteroids that could collide with the Earth in the near future, are called Near Earth Asteroids. NASA and other space agencies are tracking all the Near Earth Asteroids and are looking for a way to connect them to the Earth. As of April 2022, more than 28,000 near-Earth asteroids have been identified. More than 800 of which have a diameter of 1 km or more. This is a terrifying number. So many asteroids that could potentially collide with the Earth.
But today, there's nothing to be afraid of. Because the scientific calculations have been so advanced that we can clearly predict and calculate their path, as to where exactly they are going to go. We can also estimate the chances of them colliding with the Earth. And if they are on the path of colliding, what can we do to stop them? For this, NASA launched the DART space mission in 2021. Double Asteroid Redirection Test. Their plan was to take a spacecraft and collide with an asteroid so that the asteroid's path can be changed. And if in the near future, an asteroid collides with the Earth, we can change its path. It may sound like science fiction, but this idea has already been successful. In September 2022, it was tested with an asteroid that wasn't on the Earth's path.
NASA sent a spacecraft, collided with it, and changed its path. If it was tested with that asteroid, it could be tested with future asteroids as well. But it's not that there's no danger at all. The danger is actually from humans. The asteroid strike that killed the dinosaur is known as the 5th extinction event in the history of the Earth. After this, scientists believe that the 6th extinction event has already begun. And this is not because of a volcano or an asteroid, but because of humans. It is known as the Holocene Extinction Event. In the last 100-200 years, we have seen biodiversity loss on such a large scale. Because of the rapid extinction of different species of animals and plants by humans, biologists have given it the status of mass extinction.
The forests that are being cut down by humans, the pollution that is being spread in the sea and in the air, due to this, the current rate of extinction of species is more than 100 to 1000 times the normal rate. The habitats of the animals that exist today are being destroyed. Thousands of mammals, birds, reptiles and amphibians are now in the endangered category, or have already been extinct because of humans. To stop this crisis, the United Nations Convention on Biological Diversity meeting was held in Japan in 2010. 20 biodiversity targets were set to be achieved by 2020. Unfortunately, only 6 of them were partially achieved. In January 2020, a new Paris-style plan was created to stop biodiversity and ecosystem collapse. The deadline for this was 2030.
The purpose of this was to give 30% of the Earth's land and oceans to the protected areas. To reduce 50% of the pollution that is being spread around us. Scientists have proposed that the extinctions that are taking place, should be kept at least 20 extinctions per year. The coming time will tell us how many of these targets are being met. But one thing is for sure, it will be very important to do this. Because if the species of plants and animals are extinct today, in the same way as they were in the previous extinction events, then it may not be possible for humans to survive. And if we talk about humans, humans originated only 300,000 years ago. In Africa. This is calculated. And if you compare it to dinosaurs, which lived for 174 million years,
