As you see the world around you, it is impossible not to notice the
variety of life. Not only do species differ from each other in
form and function, but individuals within populations are different
from one another. If these differences are inherited and they are
important to survival and reproduction, then they provide the
basis for populations and species to change in response to changes
in the environment.
There is a great deal of understanding about the ways individuals
and populations evolve in today's world. But, how did life get its
start on a planet that must have been inhospitable when it first appeared
in the galaxy? Was it always the way it is now, or did the planet
itself change through time?
In this section, we will take a look at a variety of evidence that
can shed some light on the changes that must have occurred to produce
the world we see today.
As you read the papers in the course pack, think about their relevancy for:
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Northern Arizona University