How dinosaurs became extinct It is something that many people and scientists ask themselves. However, it is not known exactly, but there are several theories that are more affected by the scientific community. Such theories are based on evidence that can prove their worth. But there are many questions that are still unresolved on this subject.
In this article we are going to tell you what the main theories are about How dinosaurs became extinct.
How dinosaurs became extinct
Dinosaurs have been by far the largest reptile-related animals on Earth. They are considered a type of prehistoric warm-blooded reptile, related to but quite different from living reptiles and even birds. They lived for about 160 million years, during the Mesozoic, divided into three periods: Triassic, Jurassic and Cretaceous. They disappeared from the earth's surface a long time ago.
When and How dinosaurs became extinctThis is one of the most common questions still surrounding these animals of the past. While science has established a date and a reason for this, today, thanks to scientific advances, more details and research have emerged, more theories have been proposed, and in some cases, the date can even be changed.
The date of the extinction of the dinosaurs is believed to be about 65 million years ago. But, what is the most accepted theory of the extinction of the dinosaurs in the scientific community? For decades, it has been determined that the impact of meteorites or asteroids on Earth is likely to wipe out these long-ruling giants. However, as we have already mentioned, there are more possible reasons for this, and today, these are the most likely theories:
- meteorite or asteroid
- Volcanic activity
- Climate Change
The meteorite theory in the extinction of the dinosaurs
Between the late 1970s and early 1980s, a 12-kilometer-diameter meteorite or asteroid that hit Earth, particularly in the Yucatan Peninsula region of Mexico, was theorized to cause the extinction of the dinosaurs.
An iridium-rich geological layer or formation has been discovered that occupied the entire Earth and dates back to the time of the mass extinction. This chemical element is not commonly found on the Earth's surface, but it is present in magma within the Earth, as well as in ancient formations and meteorites that lie deep underground. Because the element is highly toxic and radioactive, scientists believe that after a large meteorite or asteroid rich in the element hits and produces large quantities of the element from the Earth's inner layers, the material spreads throughout the planet, the end of life on Earth. Many creatures and dinosaurs largely became extinct, but this wasn't the only reason; a chain reaction occurred.
The huge Chicxulub crater, discovered in the Yucatan Peninsula in Mexico, it also dates to about 65 million years ago, so it is believed to be the site of the discovery of large asteroids that expanded the iridium shell. It eventually led to this great disaster.
So the mass extinction of the dinosaurs was caused by a meteor hitting Mexico. However, it was not the impact itself that ended the lives of so many people, but rather it had a chain reaction that ended most of the life on Earth.
The reactions that led to the death of the dinosaurs were as follows:
- It was this influence that wiped out the dinosaurs in the region.
- An explosion or shock wave that creates a huge impact and phenomenon over a large area of ​​land, such as a massive tsunami. You can learn more about how a tsunami originates.
- Toxicity and radioactivity of iridium and other elements expelled from the innermost layers of the Earth as a result of ejecta from meteorite impacts.
- The massive rise in temperature was calculated to be several times that of the Sun, and even caused fires thousands of kilometers from the source of the impact.
- A thick and extensive layer of minerals and other elements that forms in the sky as a result of the impact of jets and gases from fires. The sky was primarily covered in gypsum, a sulfate-containing material that covered much of the Yucatán Peninsula at the time. The gypsum volatilizes and turns into sulfates that rise into the atmosphere in large quantities, preventing sunlight from reaching the Earth's surface. Photosynthesis stops (on land and in the ocean) due to the blockage of the sun's rays, food webs are largely disrupted, and animals can barely see, making it difficult to find food, even if it's small. After a few days of sudden air temperature drops (about 10°C), causing much of the Earth to freeze. So, due to one reaction or another, the creatures of the time were slowly dying off most of the life left on Earth. Over time, this layer dissolves and partially falls to the ground, allowing enough sunlight to come back to life to resurface the few survivors.
The theory of volcanoes was the reason for the extinction of the dinosaurs
Another theory that most supports the scientific research carried out so far is that the volcanoes wiped out the dinosaurs. There is evidence that, on the day of this extinction, there was massive volcanic activity that continued for a long time without interruption, especially in the Indian part. In fact, lava from these volcanic eruptions covered more than 2,6 million square kilometers of India. If you want to know more about previous extinctions, you can consult information on the extinction of species.
It is believed that such a catastrophe will kill all animals in this part of the planet. Furthermore, due to magma from inside the earth and volcanic lava rich in iridium, along with volcanic ash and toxic gases emitted by continuous eruptions, the dinosaurs disappeared. The difficulty of sunlight reaching the earth's surface, the increase in greenhouse gases and the toxicity of the air (which decreases oxygen) are the perfect combination to prevent many species from surviving this era.
The theory of climate change in the extinction of the dinosaurs
Finally, the last theory accepted by the scientific community about why the dinosaurs disappeared is that of climate change in the Cretaceous. There is ample paleontological evidence in geological strata and in animal and plant fossils that a chain of disasters, such as earthquakes, tides and marked drops in temperature, occurred during the final stages of the Age of Dinosaurs, leading to extreme climate change. To better understand the context of extinctions throughout history, you can read about the Permian extinction as an emblematic case.
In addition, the Earth's water level has dropped significantly due to the drastic drop in temperature. Another aspect is the major changes in the environment at that time, and these large animals cannot adapt in time.
I hope that with this information you can learn more about how the dinosaurs became extinct.
