Land bridge

Imagine you want to go to your friend's house, but there is a big river between your house and your friend's house. You can't cross the river to get to your friend's house, so you have to find another way to get there.

A land bridge is kind of like a way to cross the river without actually going through it. It happens when there is a big piece of land that connects two other pieces of land that are separated by water. For example, long, long time ago, some parts of the world looked different than they do now. They were covered with ice and that made the water in some places a lot lower than it is today.

So, some animals, like people and dinosaurs, could walk across those land bridges from one place to another. It was kind of like a bridge made of solid ground instead of wood or metal. They could cross these bridges and go to new places that they couldn't go to before because of the water.

But, after a while, the ice started to melt and the water levels rose again. So, the land bridges disappeared and the animals were once again separated by water. But, the land bridges were really important because they let different animals from different places meet each other and it helped create the world we know today.