When the continents separated, organisms were forced to be placed in different locations with different environmental conditions. In order to survive in their new environment, over time, various flora and fauna developed various body mechanisms to cope up. This brought up the speciation of flora and fauna.
The top of the Stigma is sticky and is where the pollen attaches to it.
I hope this is what you wanted
I would say immigration only.
emigration would theoretically reduce the genetic variation as unique individuals leave, but immigration would bring unique traits into circulation in an ecosystem.
I'm not super great at biogy tho so this might not be right... :)
The answer is B: no
Hope this helps!
