Natural Selection

Natural selection is a big part of evolution. It is how nature decides which animals and plants do well. Living things that fit their home better are more likely to live. They grow up and have babies. Their babies get the same helpful traits.

Survival of the Fittest

In nature, life can be hard. Animals must find food, stay safe, and raise babies. Some are faster, stronger, or better hidden than others. These animals are more likely to live long enough to have babies. Over time, their traits become common.

Drawings of four Galapagos finches with different beak shapes.
Drawings of four Galapagos finches with different beak shapes. (John Gould (14.Sep.1804 - 3.Feb.1881) / Wikimedia Commons)

An Example

Imagine rabbits in a snowy place. A white rabbit blends in with the snow. A brown rabbit is easy to see. Foxes can spot the brown rabbit more easily. The white rabbits live longer and have more babies, so most of the rabbits end up white.

Fun Facts

  • Giraffes got long necks to reach high leaves.
  • Some bugs look just like leaves to hide from birds.
  • Cheetahs became fast so they could catch their food.

Did You Know?

Natural selection still happens today, even in tiny germs that can change to fight off medicine.