The image is of a seagull, a member of the animal kingdom.
The Origin of Life on Earth
At one time or another, we've probably all wondered how life first got
started. This is not an easy
question! There are at least three kinds of explanations for how life on
1) Life was created. Some people believe that life on Earth was created
by a supreme being or spirit. These ideas have been around for a very
long time and differ among different cultures and religions. We can't use
science to test these ideas, so we leave it to each person to decide for
him- or herself.
2) Life began somewhere else in the universe, then arrived on Earth
later, such as with the crash of a comet
3) Life began on Earth by chance. Many scientists believe that life
began as the result of complex chemical reactions that took place in the
Earth's atmosphere 3.5 billion years ago. When chemicals in the
atmosphere interacted with
the electricity from lightning, certain substances formed that were
necessary for early forms of life
. In the 1950's, two
biochemists conducted an experiment
showed how this could happen in the laboratory.
Shop Windows to the Universe Science Store!
"Science, Evolution, and Creationism
", by the National Academies, provides fascinating background on these topics for all, and is particularly useful for the Earth and space science classroom. Check our other books
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