How long did the Dinosaurs live?
Dinosaurs lived on Earth between 165 and 177 million years ago. They first appeared between 243 and 231 million years ago, during the Triassic period (We'll learn more about the Triassic and other geologic periods later in the article). The dinosaurs became extinct about 66 million years ago. This means they were on Earth much longer than they were extinct. 🦖
Dinosaurs were very successful, especially considering that modern humans (Homo sapiens) have only been around for 200,000 years. Today, many scientists consider birds to be dinosaurs! In fact, during the Jurassic period, a branch of dinosaurs began to transform into birds. 🦅
Therefore, when we talk about "dinosaurs" on this page, we are referring to "non-avian" dinosaurs, that is, all dinosaurs that did not evolve into birds.
How long did the dinosaurs live: in numbers
A million in numbers is "one" followed by SIX "zeros", that is: 1,000,000. Therefore, in numbers, the dinosaurs were on Earth for as long as 177,000,000 years. That's a long time! While we're on the subject of big numbers, you might be interested to know that the Earth was formed about 4.54 billion years ago. A billion in numbers is "one" followed by NINE "zeros", which is: 1,000,000,000. 🌍
Therefore, in numbers, the Earth formed 4,540,000,000 years ago. Life began to appear about 3.5 billion (3,500,000,000,000) years ago. 🧬
So, in the grand scheme of things, even dinosaurs, which were on Earth for 177,000,000 years, are relatively new!
When did dinosaurs first appear on Earth?
As we have seen, dinosaurs appeared on Earth between 243 and 231 million years ago. They evolved from a group of reptiles called Archosaurs. This was during the Triassic period, which is part of what is called the "geologic time scale".
History of Dinosaurs: The Geologic Time Scale
In the geologic time scale, time periods correspond to rock layers. For example, the Triassic period refers to the time period in which the rock in the Triassic layer formed. 🏜
Just as days are divided into hours and minutes, so are the units of the geologic time scale. An era is divided into periods, which in turn are divided into epochs. You can learn more about the geologic time scale and the age of dinosaurs here: Dinosaur Periods.
The Dinosaur Era: The Mesozoic
Dinosaurs existed during the Mesozoic Era, which is divided into 3 periods: the Triassic, Jurassic and Cretaceous. Dinosaurs appeared on Earth in the middle of the Triassic period. They became the dominant land animals around the beginning of the Jurassic period. They were on Earth until the end of the Cretaceous period. 🦖
At the end of the Cretaceous, something happened that caused the extinction of not only the dinosaurs, but 75% of all species on Earth! Scientists now believe that the most likely explanation for the extinction of the dinosaurs is that the Earth was hit by a large asteroid. You can read more about the extinction of the dinosaurs here: The causes of the extinction of the dinosaurs
Are Dinosaurs Really Extinct?
Strictly speaking, dinosaurs still exist on Earth. As we have seen in many of our dinosaur pages, scientists now consider birds to be dinosaurs. This is because the animals are grouped into branches. Because a group of dinosaurs "branched off" and evolved into birds, they are still considered dinosaurs. 🐦
Therefore, instead of becoming extinct at the end of the Cretaceous period, dinosaurs are still alive and well, and living in your backyard!
The Story of the Dinosaurs: 10 Facts
- The Dinosaurs lived on Earth for 165 to 177 million years.
- Dinosaurs appeared between 243 and 231 million years ago.
- It was during the Triassic period.
- Dinosaurs evolved from a group of reptiles called Archosaurs.
- The Triassic, and other periods on the geologic time scale, correspond to layers of rocks. ⛰
- The Earth formed about 4.54 billion years ago. (It was 4,540,000,000 years ago in figures).
- Life appeared on Earth about 3.5 billion (3,500,000,000,000) years ago.
- Homo sapiens (humans) have been on Earth for about 200,000 years.
- Many scientists now consider birds to be dinosaurs, so dinosaurs are still on Earth!
- All non-avian dinosaurs became extinct at the end of the Cretaceous period, about 66 million years ago. ☄️
Dinosaur history: conclusion
In this article, we found out that dinosaurs were on Earth between 165 and 177 million years ago. We also discussed the geological time scale and finally that scientists believe that dinosaurs still exist in the form of birds.
