Q1. As we know that natural selection will not result in evolution if a trait is not heritable. However, it is also possible that a trait with heritable variation will not show an evolutionary response under natural selection. Name and describe 2 types of natural selection that do not necessarily change allele frequencies despite the existence of heritable variation, and give an instance (real or hypothetical) of each.

Explain in details.

Q2. After a long scuba diving session on a Caribbean reef, David boards a plane to Denver. He begins to feel pain in his elbows on a flight back home to Denver. What will occur to him (including treatment)? Could it be avoided and if so, how?