The dinosaurs lived on Earth for more than 200 million years. They were among the largest and most powerful animals ever to walk the planet. But something happened to them, and they all died out suddenly about 65 million years ago, possibly because of a massive asteroid impact. Scientists now know that the dinosaurs were already in trouble before their demise. They had become so large and dominant that they couldn’t evolve fast enough to cope with environmental change. There are theories about what would happen if a giant asteroid hit Earth today, but scientists don’t know how much damage it would cause.
Dinosaurs were not just large reptiles, but also a complex group of animals that were warm-blooded, had feathers and were herbivores. They lived on the Earth for more than 200 million years. The first dinosaurs evolved from archosaurs, which include crocodiles, lizards and birds. Dinosaurs lived on all continents except Antarctica. They are easily distinguished by their long necks and tails, as well as their large bodies with small heads and teeth. All the different facts you should know about the dinosaur-universe.com.
Did A Comet Actually Kill the Dinosaurs?
Scientists have recently announced that a comet impact killed the dinosaurs. This would have happened about 66m thousand years ago (see Time of the Dinosaurs for more details). The rock that struck the Earth produced what was known as an impact winter, which lasted for about 10 years. This did not kill all cold-blooded animals and it may be that these animals adapted to survive this event by migrating and changing their habits, so nothing species died off completely.
The comet that killed the dinosaurs only had to have a diameter of 100 km. It simply burst into a single point with an explosion equal to 100 billion megatons of TNT on April 28, 65 million years ago. The heat from this explosion could have incinerated large portions of Earth’s surface, as well as all life on the planet — including humans.
Understanding The Timescale of Dinosaur Evolution
Around 230 million years ago, during the Triassic Period, the first dinosaurs debuted. They were reptiles with small forelimbs and no hind limbs. They had a biological clock that was similar to the mammals’ diurnal rhythm — they woke up at dawn and slept at night — so they did not migrate like some reptiles do today.
In addition to living in trees, some early dinosaur species also walked on four legs like modern reptiles do today; others had only two legs or four legs; some could swim; some flew through the air like pterosaurs (flying dinosaurs); others could run along the ground like modern mammals do today; still others were so fast they could outrun many other dinosaurs in pursuit of prey (fast runners).
What Happened with The Dinosaurs?
The most common cause of death for dinosaurs is starvation. Not all dinosaurs were herbivores, but those that ate a lot of plant material. As the plants died, more and more animals were forced to eat them. The problem was that most living animals are not very efficient at digesting plants, and so they began to starve as well. Dinosaurs also succumbed to disease, especially when their immune systems were weakened by malnutrition. Some dinosaurs were killed by large predators such as T-Rex or Spinosaurus (a type of Carcharodontosaurus). Others were killed by catastrophic events such as asteroid impacts of volcanic eruptions.
Dinosaurs were not cold-blooded animals. They needed to be warm to survive. Dinosaurs had feathers, which are thin and light, but they also had scales that were thick and heavy. When dinosaurs walked on land, their body heat from the sun could have warmed them enough to keep them comfortable. But when dinosaurs flew through the air, it was very cold. The answer is that dinosaurs died in many different ways. Some lived in cold water; some lived at high elevations; some lived on hot deserts; and some lived where there was no water at all.