Embryonic tissue supporting filling and photosynthetic
Ground tissues conducting
Vascular tissues and covering
Dermal tissue
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... :)
Among others, both plants and animals need oxygen and water. They also both need space and air.
4 mps increase in 10 seconds = 2 mps increase in 5 seconds = .4meters/2sec
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