Mesozoic Era

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The Mesozoic Era existed from 225 mya to 65 mya. The Mesozoic Era is divided into three periods of time. These periods are:  the Triassic, Jurassic and Cretaceous.

Triassic 225 mya to 195 mya

The Triassic Period lasted 30 million years. The Triassic is called "the age of dinosaurs." Shortly after the asteroid strike, the dinosaurs and mammals were left on Earth. Dinosaurs, being reptiles, had advantages over mammals in that they were "ready to go" when born, they could reproduce higher numbers of young and they were larger.  This helped dinosaurs take control of the Earth during this period.

Jurassic 195 mya to 135 mya

The Jurassic Period lasted 60 million years. The Jurassic saw many changes in dinosaurs during this period. The dinosaurs were mainly herbivores in that they ate plants. The dinosaurs of this period grew to 140 feet long in some cases! The Jurassic is often marked as "the first time period when life existed in the sky." The first bird-like dinosaur was called the Archaeopteryx.

Cretaceous 135 mya to 65 mya

The Cretaceous Period lasted for 70 million years. The Cretaceous is known as "the age of the carnivores." This time period saw the rise of meat eaters such as T-Rex, which required 2 tons of meat a day to survive.  The Cretaceous time period saw the first flowers on plants. The Cretaceous is also marked by a mass extinction event that ended the Mesozoic Era. An asteroid around a few miles in diameter struck the Earth at the Yutan peninsula in Mexico. This created a global dust cloud around the world and wiped out 65% of all life on Earth. This ended the age of the dinosaurs. Dinosaurs were extinguished by five reasons:

1. They grew too big to support their feeding habits.

2. They suffered from diseases such as cancer.

3. Their climate changed as the continents moved to northern or far southern latitudes.

4. Mammals, such as rats, destroyed their eggs faster than they could produce them.

5. The asteroid strike was the final blow.

There is a theory out there that suggests that dinosaurs became birds, and there is some evidence to support that. Next time you see a bird, maybe T-Rex is looking back at you!