Exploratour: Life on Mars?

Short-eared owl
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Corel Photography

What is Life?

This tour wouldn't be complete without looking at...What is life? Does this seem like a strange question to you? Well, let's think about it. If you had to explain to someone what "life" is, what would you tell them?

Do all living things move? Do they eat and breathe? Even though we all seem to know what is meant by saying something is "alive", it's not very easy to describe what "life" is. It's almost as hard as describing where life came from.

The study of life is called "biology" and the people who study it are "biologists". They even have a tough time describing what life is! But after many years of studying living things, from the mold on your old tuna sandwich to monkeys in the rainforest, biologists have determined that all living things on Earth, do share some things in common:

1) Living things need energy
2) Living things grow and develop
3) Living things respond to their surroundings
4) Living things reproduce



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