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.Know More
The asteroid impact theory suggests that dinosaurs died in a massive extinction as a result of a large asteroid hitting the planet. Evidence that supports this theory includes the presence of a metal called iridium in places where dinosaur fossils have been found. Iridium is a rare metal that is not commonly found on Earth, but is a common material in asteroids. Scientists believe the impact from the asteroid could have lead to the development of tsunamis and forest fires, as well as creating a layer of dust and ash that blocked out the light from the sun, plunging the planet into darkness and cold.
Other theories suggest that there was an increase in volcanic activity around the time that dinosaurs went extinct and they believe this activity would have destroyed habitats and pushed enough ash into the atmosphere to affect the climate and destroy vegetation.
The climate change theory states that Earth's climate gradually became cooler and drier, and that dinosaurs could not adapt to the change, leading to their gradual extinction.
Religious theories support the idea that dinosaurs died during the great flood in Noah's time.
While the topic of how dinosaurs went extinct is still up for debate, discoveries of new fossils offer more information about how they lived.Learn more about Dinosaurs
There are a few well-researched theories about why dinosaurs are extinct; one of the most prominent theories hypothesizes that a massive asteroid impact killed off the dinosaurs. Another states that heavy volcanic eruptions across the Earth may have been responsible.Full Answer >
True dinosaurs were not swimmers. There were a number of very large aquatic reptiles that lived during the age of the dinosaur, but they were not technically dinosaurs. These creatures belonged to one of several other groups, such as ichthyosaurs, plesiosaurs and mosasaurs, which were types of marine reptiles.Full Answer >
There are some animals on earth that can be traced back to the Mesozoic Era when dinosaurs walked the earth; these animals include monotremes such as the duckbill platypus, reptiles such as the crocodilians and sea creatures such as the sea urchin. For the most part, the animals that are alive today have made evolutionary changes from the forms they had when dinosaurs were alive. For example, though the event that caused dinosaurs to die out also killed many other reptile species, several surviving reptile species have direct ancestors from that era, including the crocodilians, which are smaller than their Mesozoic ancestors.Full Answer >
The smallest known dinosaur species include the Minmi, Pakicetus, Europasaurus, Phosphatherium, Microraptor, Raptorex, Microceratops, Lariosaurus and Nemicolopterus. These are all examples of the smallest dinos in a particular group, such as the smallest Raptor (Microraptor), which weighed around 2 pounds and was small enough to eat insects, and the smallest Tyrannosaur (Raptorex), which likely topped out at about 150 pounds.Full Answer >