The end of the dinosaurs is one of the greatest mysteries of paleontology. The leading theory of their extinction involves a massive meteor impact, possibly the one that created the Chicxulub crater in Mexico. Alternative theories include multiple global impacts, a sudden change in the sea level and a worldwide increase in volcanic activity that drastically altered the atmosphere and global climate.Know More
According to the Alvarez Hypothesis, the extinction of the dinosaurs occurred as a result of a massive comet or meteor impact. One of the major pieces of evidence that supports this hypothesis is a layer of iridium found in clay that marks the boundary between the Cretaceous and Paleogene periods, which is when the dinosaurs went extinct. In the 1990s, geologists discovered a 112-mile-wide crater just off the Yucatan peninsula that provided evidence of just such a massive impact occurring around the same time as the extinction.
A few questions remain unanswered, however. A single impact would have had devastating effects on the environment, but most of the dangerous changes, such as an increase in acid rain, would only last a decade or two after the event. The dinosaurs' extinction occurred over a more extended period of time, bringing up the possibility that multiple impacts, possibly including the one that caused the Shiva crater in India, may have contributed to the extinction.Learn more about Dinosaurs
Scientists believe that the earth looked much different during the dinosaur's lifetime than it does today; at the advent of dinosaur life, all of the landmass on earth made up one single super continent known as Pangea. Dinosaurs likely did not live on every part of Pangea, instead concentrating in certain areas, including the land that is now known as Argentina, which is the home of the oldest known dinosaur fossil. Certain dinosaur species may have been localized to certain parts of the world, including the T.Rex, which has only been discovered in fossils found in North America.Full Answer >
Though there were some dinosaurs with mammal-like qualities, dinosaurs were actually reptiles; however, though the word "dinosaur" roughly translates to "terrible lizard" in Greek, dinosaurs were not actually lizards, either. Dinosaurs represent a distinct group of reptiles that is now extinct, though there may be some living animals, including some birds, that are distant evolutionary relatives of the dinosaurs. The animals described as being mammal-like dinosaurs were actually early relatives of the dinosaur, and they were the dominant land animal about 260 million years ago, as opposed to the dinosaur, which was the dominant land animal about 231 million years ago.Full Answer >
There is not sufficient proof as to why dinosaurs went extinct, but experts believe it is related to geological events, diseases, climate change and lack of plant life for sustenance. The last known dinosaurs, according to their fossils, existed about 65 million years ago.Full Answer >
There are multiple theories as to why dinosaurs died out, such as asteroid impact, volcanic activity, and climate change. There are many theories because none has been proven to be 100 percent certain as the reason for the dinosaurs’ demise.Full Answer >