Are dinosaur index fossil


The different dinosaurs

Not every dinosaur is a dinosaur. In the Middle Ages, which began 230 million years ago and ended 65 million years ago, dinosaurs conquered almost all habitats on earth.

Giant marine dinosaurs up to 25 meters long cruised the seas. Horned, armored dinosaurs equipped with razor-sharp claws and teeth roamed the mainland, while pterosaurs with wingspans of sometimes over ten meters rose into the air.

But these three groups of dinosaurs were not related to each other and developed separately. That is why the dinosaurs can be clearly distinguished from the marine and pterosaurs. They only include the dinosaurs that lived on the mainland during this period.

Dinosaurs in Germany

Here in Germany, too, there are traces of dinosaurs. The Solnhofen limestone in Bavaria is one of the most important fossil deposits in the world. All known fossils of the famous Archeopteryx come from this place, with some exceptionally well-preserved details.

Northern Germany, on the other hand, is known for its dinosaur tracks: they are some of the longest in the world. A whole herd of sauropods, gigantic herbivores and also huge predatory dinosaurs have left their footprints in Lower Saxony. The first indications of sickle-clawed dinosaurs ("raptors") in Europe were also discovered there.

Smarter than expected

When they were discovered in the 19th century, dinosaurs were considered downright stupid and solitary. Most of the reptiles living today hardly show any social behavior.

In the course of time, however, more and more discoveries have shown that these properties cannot simply be transferred to all dinosaurs. At least some species lived together in an orderly manner, which required an intelligence comparable to that of mammals and, above all, birds.

Caring brood care

The majority of dinosaurs, like most reptiles and birds, hatched from eggs. The largest dinosaur eggs found so far are 30 centimeters long and hold three to three and a half liters.

While reptiles usually just lay their eggs and then don't care about the clutch, the breeding behavior of some dinosaurs is more reminiscent of that of birds. Because some types of dinosaur built nests and incubated their eggs.

In Mongolia, researchers were able to uncover the fossils of an Oviraptor, which was probably caught by a sandstorm while it was breeding and tried to protect the nest with its outstretched arm.

Some dinosaurs continued to care for their young after they hatched. The Maiasaurier even formed whole nest colonies and looked after their offspring for a long time.

Out and about in a group

Unlike most reptiles, the dinosaurs also formed groups for other purposes and must have the intelligence necessary to communicate. The small, bird-like predatory dinosaurs such as velociraptors and saurornithoides, which chase after their prey in hunting groups, are considered to be particularly clever.

Footprints also show the social behavior of some herbivores who had banded together in herds. In a rock layer in Texas, 20 tracks running side by side were discovered by giant dinosaurs. The prints suggest that the young animals moved in the middle of the herd, where they were protected from predators.

The secret of success

Some dinosaurs had terrifying claws and teeth, while others grew to perhaps 40 meters long and weighed 100 tons. Their size and imposing weapons are certainly an important reason for the enduring fascination with dinosaurs.

However, the reference to some martial phenomena hardly explains why these were able to prevail against other animal species for an entire geological age. Because dinosaurs came in very different sizes and many were not prepared for open combat.

Many researchers attribute the dinosaurs' success to their running skills. Because the dinosaurs differ from most other reptiles by their leg position. The dinosaur legs are just below their body and do not come off to the side. The straight legs allowed the dinosaurs to move faster and, above all, more permanently.

Most other reptiles, on the other hand, can only crawl with their pairs of legs and are designed for long, energy-saving breaks.

Like the birds

The spectacular discovery of the Archeopteryx around 150 years ago was the first evidence of the long-disputed relationship between birds and dinosaurs. Since then, more and more similarities between birds and dinosaurs have come to light.

Even the giant dinosaurs had bones with cavities that allowed the greatest possible stability with reduced weight - this bone construction also gives birds the weight advantage that is crucial for flying.

Some herbivores among the dinosaurs, like birds, swallowed stones to break up the food in their stomachs. And some dinosaurs built nests, incubated the eggs, and cared for their offspring - just like birds.

Well-known dinosaurs in a new look

Feathers, too, are not an achievement of birds. In the past few years, four new feathered dinosaur species, the Proto-Archäopteryx, Caudipteryx, Sinosauropteryx and Sinovenator, have been discovered in China, some of which are very closely related and almost as old as the Archeopteryx.

According to the latest research, not only the small, bird-like predatory dinosaurs, but also larger dinosaurs had feathers. For example, New York researchers Alan Turner and Mark Norell discovered bony knobs on the forearm of a Velociraptor that were previously only known from birds to attach flight feathers.

The scientists therefore assume that the Velociraptor had feathers for thermal insulation, comparable to those of today's birds.