Mutations result from an error in DNA replication, should it be from an alien source (like radiation) or simply a mistake in replication.
Migration of organisms to a new population would alter the DNA by adding new genes, but it would not mutate them.
Answer:
A.) Pollen are well preserved in the sediment layers because they are highly resistant to decay.
B.) Other indicators that can be used to determine past climates are through the analysis of the width of tree rings and the coral reefs formed underwater.
Answer:
It is the cycle when the reproductive organs start to fertilize. Another form of this is called the menstural cycle when natural changes in the uterus and ovaries to make reproduction possible soon.
