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.
Changes in the dna are called mutations. They can occur spontaneously. Mutations can only be passed down in gametes--sperm and egg cells. with Darwins theory at mind a mutation needs to pass the test of natural selection to remain in the gene pool. So purposly making mutation or altercations may end in diseases/illnesses or in some cases death because they body can not take it.....hope this helps if it doesnt im sorry!
