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... :)
iconic bond -> sharing of many electrons
metallic bond -> sharing of electrons
covalent -> transferring of electrons
hope this helps...
Because some of them are immune and only works for one thing in the system
What is the question your trying to have answered?
