Some organisms have a large geographic range. For example, the Norway rat lives on every
continent except Antarctica.
A population of Norway rats is the number of rats
in one particular area. Do you think it's
scientifically possible for a population of Norway
rats in North America to carry different genetic
mutations than a population of Norway rats in
Africa? Do you think it's possible that they carry
some of the same mutations? What types of
information can scientists learn by studying the
genomes of these two populations of rats?