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... :)
Answer: i think its B or C
Answer:
D geothermal
Geothermal energy is harnessed beneath the Earth's surface.
B. some substances must be dissolved in water before they can be used
Answer:
Sand
Explanation:
Space, water, energy, and air are all needed for an organism to survive. Sand is just somewhere an organism could accustom to live in that environment.
