There's a shrink to the upward thrust of a sand dune. they do no longer stay interior a similar place yet crawl downwind and are replaced by capacity of latest ones. at last, they attain the factor the place they'd be stabilized by capacity of plant existence. Barrier islands are formed a similar way, different than by capacity of water, somewhat than wind.
A parasite invades the species and causes its population to decline because a biotic factor is a living factor that affects a species
