You're listening to Sleep Tight Science. Did you know long before the age of dinosaurs, monster dragonflies cruised through the air?

What?

Some were the size of seagulls.

Wow! Hello! Hello, friends and welcome back to Sleep Tite Science, a bedtime show that answers the questions you have about science.

In this episode, we will start to learn all about dinosaurs

and try to answer some of the questions you, our listeners,

have submitted about these fascinating creatures.

We will learn about them by following along with a story of a little bear named Bernice,

who, if you listen to Sleeptight stories, you might already be familiar with.

Bernice has many interests, including science, and Papa Bear and other friends will help her learn.

Before we continue with our story,

let's start learning about dinosaurs.

Before we start talking about these massive animals that roamed the earth,

we must understand a little bit about the earth and life itself.

The earth is around 4.6 billion years old.

We know this from dating the oldest rocks. For almost the first one billion

years, the Earth was lifeless. How life began is not clear, but the process required water,

acids, and other chemicals.

The first living molecules developed into simple, single-celled life forms floating in the oceans.

The oldest evidence of life forms are bacteria and algae fossils found in rocks that are 3.8 billion years old.

From these simple beginnings, life branched out in many directions.

The two main branches were plants and animals.

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