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Natural Selection Definition

Natural selection is the process of organisms changing over time. Organisms with traits better suited to their environment tend to survive and reproduce.

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Natural Selection

Fun Facts

  • Natural selection could affect humans when bacteria that can make us sick changes.
  • Natural selection can lead to evolution, which is why there are no longer giraffes with short necks.
  • The process of natural selection is also referred to as survival of the fittest.

Why Do We Need To Know About Natural Selection

Learning about natural selection helps us understand how and why certain animals and plants change over time, gaining traits that help them survive better. This idea is used in real life, like in farming where we’ve made crops like corn much different and better than their wild versions through selective breeding. This means choosing the best plants or animals to create the next generation. The same goes for raising animals like sheep to get better wool.

This knowledge is also important in medicine, especially to understand why some bacteria become resistant to antibiotics. Scientists studying old bones and fossils use what they know about natural selection to figure out how life on Earth has changed through millions of years. Knowing all this helps us fight diseases better and protect different kinds of plants and animals.

Frequently Asked Questions

What is trait variation? Give an example.
Trait variation is when organisms in a population have differences in the traits they have. For example, the giraffes have long necks, but not all their necks are the same length.
How can the environment affect an organism’s traits? Give an example.
A change in the environment can affect an animal’s ability to hide from a predator. For example, we saw that when the environment changed, the hawk ate the light-colored pocket mouse instead of the dark one because light one was easier to see.
What is natural selection?
Natural selection is a process in which some living things survive better in their environment and are able to reproduce and pass on their genes.
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