Lastly, we need to learn about spores
and dormancy.
Some organisms have the ability to create spores:
offspring that can reproduce and become viable individual
organisms.
What is special about spores is that they can potentially be dormant
for a substantial amount of time -- years, hundreds of years? --
before reviving. Spores can potentially survive adverse conditions quite well.
Dormancy is a period of metabolic inactivity and suspension of metabolic processes. An organism which is dormant can be revived under proper conditions. In addition to some spores, which can have long periods of dormancy, some organisms can be dormant for many, many years ...
like 30 million years!