A whole different world far in the past, animals that none of us ever met. Around 245 million years ago, dinosaurs first appeared on Earth and dominated it until roughly 65 million years ago. This is a huge period of time, and there is a lot that we can discover about them and the past on our planet Earth.
In general, dinosaurs belong to the reptile group. The often huge animals lived on earth for nearly 180 million years. Most of them died out by the end of the Cretaceous Period, about 66 million years ago. However, there are still some kinds that evolved into birds or other reptiles that we still have today.
The name dinosaur originated from the Greek words deinos, which means “terrible” or “fearfully great”, and sauros, which means “reptile” or “lizard”. When first discovered, it was quickly clear that these animals were different from other known reptiles. Firstly, they were large yet obviously terrestrial; they had five vertebrae in their hips, whereas most known reptiles have only two; and rather than holding their limbs sprawled out to the side in the manner of lizards, dinosaurs held their limbs under the body in columnar fashion, like elephants and other large mammals.
There are more than 1000 different species, with more and more getting added with the scientific explorations around the world, even though there are not always complete researches or finds and the reconstruction of the dinosaur happens based on fragmentary materials.
What we definitely know is that dinosaurs were diverse animals with widely varied lifestyles and adaptations. Pterosaurs, for instance, were the first animals after insects to evolve powered flight, which means they actually fly by flapping their wings. These have also evolved into a dozen species. The size can vary from as small as a paper plane to as big as an F16 fighter jet. The Tyrannosaurus rex is probably the best-known dinosaur and was, at the same time, one of the fiercest predators of all time. Around 12m long and 3,5m tall, with a massive body, sharp teeth, and powerful jaws, they could crash a car. That is basically the opposite of Albertadromeus. These kinds of dinosaurs were the smallest known from Canada. They only ate plants and reproduced by laying eggs. In comparison to an average man, it would reach up to about the knees. The Albertadromeus was close to the bottom of the food chain of dinosaurs and probably also belonged to a normal meal for T. rex.
It is quite astonishing that we know that much about a time period that is so long in the past, but thanks to dinosaur fossils and tracks that have been discovered throughout human history, we can have an image of what their lives might have looked like in the past. Not even that long ago, in 1842, Richard Owen introduced the term dinosaur. The remains of them might already have been found before that year, but they could never be classified or understood. After Owen’s announcement, many kinds of dinosaurs were discovered all around Europe and England and given names. Shortly after, the first life-size models were created. A lot of research was done in the years after, and all the found fossils were first discovered and then analysed by scientists from all over the world.
With this research, we also got to know more about the reasons why humans were never able to see dinosaurs in real life, or, in other words, when and why dinosaurs went extinct. This happened around 66 million years ago; however, some records from North America show that dinosaurs had already declined during periods before. This is very complex and difficult to attribute to a single source. First, we have to understand that evolution happened naturally, even during the time of dinosaurs. Different species evolved rapidly and were quickly replaced by others throughout the Mesozoic. There were completely different species living in the different epochs. It was a continuous process of dying out and renewing dinosaurian life. Another point is the K-T boundary. Whatever factors caused it, there was undeniably a major, worldwide biotic change near the end of the Cretaceous. The best-known change here is the dinosaur. Many assumptions and theories were made about what exactly happened there. One of the ones that was actually possible and seriously taken into consideration is the so-called asteroid theory. It does not explain all the details of the K-T boundary and all the extinctions that happened, but it definitely gives some indications. It basically states that an asteroid collided with the Earth and caused the extinction of many animals. Sunlight was possibly blocked for several years, and this had an impact on plant life, which influenced the lives of dinosaurs as well. Nevertheless, the birds that we know today are still direct descendants of the giant, extinct dinosaurs, and crocodiles and alligators are close relatives.
If your biggest dream is to see dinosaurs in real life, looking up at the sky and seeing birds fly is actually pretty close to it. I hope you learned some new and interesting information in this article. Have a nice day!
Sources
https://www.britannica.com/animal/dinosaur