Dinosaur extinction theories are many and diverse. Here, grouped in this article, theses most accredited by scientists to explain the sudden extinction of the great prehistoric lizards.
Dinosaurs are a diverse group of extinct animals that for the 160 million years were the dominant vertebrates on the surface of the globe, specifically from the late Trio (about 230 million years ago) until the end of the Cretaceous (about 65.5 million years ago).
Most types and species of dinosaurs disappeared during the extinction event of the Cretaceous-Triangular period, and scientists have believed for a long time that they did not leave behind any proportions, but that assumption proved wrong, as researchers discovered later that birds are the closest relatives of the remaining dinosaurs in the current era, and that Through what emerged from the fossils linking the two species, as it turned out that all birds today descend from a common ancestor that evolved from the Theropod dinosaurs during the Jurassic period. Also, most modern classifications place birds as a surviving group of dinosaurs.
Dinosaurs are considered one of the most diverse groups of the animal kingdom. Their descendants are the most diverse vertebrates on the face of the earth, with more than 9,000 species. Ancient biologists have been able to identify more than 500 species and 1,000 different types of non-avian dinosaurs, and today different forms of dinosaurs can be found on all continents of the world, whether they are living as represented by birds, or death that are defined by their inducers. A number of dinosaurs were herbivores and others were carnivores, and some of them went on their hind legs, while others went on four legs, and some were able to navigate using the two methods. Many non-avian dinosaurs have developed external extensions of their skeleton that have a physical shield, bone collar, or antlers, and some species have achieved worldwide fame for the strangeness of their exterior shape as scientists imagine. Bird dinosaurs have dominated the atmosphere of the globe since the extinction of winged reptiles, which were considered their main competitor and the main reason for inhibiting their evolution. Dinosaurs are famous because of the size of some huge species, which generates an idea for the general public that all these animals were giant, but in reality, most dinosaurs were the size of a human or even smaller. It is known that most species of dinosaurs used to build nests to lay eggs and incubate them until hatching.
The skeletons of dinosaurs displayed in museums around the world have become important tourist attractions since the first fossil fossils were discovered in the early nineteenth century, and these animals became a symbol of global and local culture for some countries. Dinosaurs have been photographed in many novels and movies that have achieved great success and a huge sales percentage, such as the series “Jurassic Park”, as well as any new discovery of great importance is covered by various media and presented to an audience interested in these matters.
The term dinosaurs
The term Dinosauria (Latin: Dinosauria) was formally formulated in 1842 by the English scholar, Sir Richard Owen who used it to refer to the “tribe or distinctive layer of orchid reptiles” that had been identified in England and around the world. The term is derived from the Greek words: “dinos” (in Greek: δεινός) meaning “great”, “strong”, or “amazing”, and “Soros” (in Greek: σαύρα) meaning “greatness” or “creeping”. Although the scientific name is often interpreted as a reference to dinosaur teeth, claws, and other frightening properties, Owen intended to refer to the size and fear of the dinosaurs.
The word “dinosaur” is used in colloquial English sometimes to refer to something unsuccessful or a failed person, even though dinosaurs have dominated the Earth a hundred and sixty million years, and the breeds of descendants of their birds spread and diversified. The term “dinosaur” is used in the Arabic language, in general, to refer to these animals, which is a distorted word for “Dinosaur” in English, and some are written by “dinosaur” as in the French word “Dinosaure”.
During the middle period during which dinosaurs lived for 165 million years, the world witnessed many changes on the planet, the most prominent of which was the erosion of continental sites and climate change, which greatly affected the life of dinosaurs and their environments. But these reptiles generally inhabited during the period of existence on the ground all seven continents, including Antarctica, Australia, and all other continents.
At the beginning of the Triple Age, only one giant continent called Pangea was covered in the earth, and the climate of the world at that time was a little hotter than it is today, and this linking of continents was extremely important in enabling the transport and spread of dinosaurs between the continents. The first known real dinosaurs were the Euraptor and the thesaurus, whose remains were found in Argentina in the layers of the Triple Age, and therefore scientific studies of evolutionary relations and biogeography are the continent of South America, the cradle of dinosaurs and the birthplace of the first. And given that all the land was then united in Pangea, the regions of these reptiles expanded rapidly to include the continents of North America, Africa, and Europe as well as South America itself, and despite this, there were still a few types of dinosaurs at the time, so each species was It occupies a relatively wide geographical area. This widespread triple dinosaur makes it difficult to study, track their diversity and spread.
With the advent of the early Jurassic period (200 – 170 million years ago), the Pangea continent was still somewhat interconnected, and land links remained between all seven continents, and therefore dinosaurs and other terrestrial vertebrates retained their unique rate of endemism that was unusually low with the contact of the world Together. During this period (Jurassic period), dinosaurs began to dominate and impose real control over terrestrial life forms, as well as increased their geographical spread throughout the world. During this era, approximately 180 million years ago, the Pangea continent began to unravel, causing many geographical and climatic changes on the planet. During that period, the poles of the poles began to melt and the sea level began to rise and submerge huge areas of the planet’s lands. This, in turn, increased the level of moisture and then rain, so the climate became more moderate while forests rich in various forms of life grew, and these environmental conditions helped the dinosaurs to increase their numbers and dominance. The continents also began to disintegrate and isolate themselves from each other quickly at this time. In the late Jurassic period, North America drifted north, separated from South America, and thus North America, together with Europe, formed part of the Eurasian continent, while the South remained united with Antarctica, the Indian subcontinent, and Australia. Forming Gondwana before Australia drifted away, beginning its long, ongoing isolation to this day. With this rapid disintegration and isolation of the parts of the world from each other, the dinosaurs began to lose their ability to move between continents, and the levels of endemism at their species began to rise, while the dinosaurs of each continent began to evolve separately from the dinosaurs of other continents.