What is evolution?

Evolution is when living things slowly change over time to better fit where they live.

Imagine you have a big box full of different kinds of snack bags, some with chips, some with cookies, and some with candy. Now imagine that every day, you pick the bag that tastes the best to you. Over time, you might end up picking mostly the same kind of bag again and again.

That's like what happens with animals and plants. If a bird has a beak that helps it eat the best food around, it’s more likely to survive and have babies. Those babies might also have good beaks, so they get to eat the best food too. Over many years, this can change how all the birds look, just like how you might end up with mostly the same kind of snack bag.

Sometimes, things in the environment change, maybe a new kind of food appears or a storm washes away some of the old snacks. Then the birds need to find new ways to eat, and maybe some of them have beaks that work better for this new food.

That’s how evolution works: small changes happen over time so living things can stay happy and healthy in their world.

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Examples

  1. A giraffe with a longer neck can reach leaves higher up, so it survives better and passes on its long neck to its babies.
  2. Fish in a pond slowly change color to match their environment over many generations.
  3. Some bacteria become resistant to antibiotics because of random mutations.

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