Awindstorm transports a few seeds of a plant species from island a, where the species is abundant, to island b, where prior to this event the plant species was not found. the environmental conditions on the two islands are very similar, but the islands are located far away from one another. over time, a small population of this plant becomes established on island b. a biologist samples plants on both islands and finds that allele frequencies on island a differ substantially from allele frequencies on island b at several genetic loci not known to affect survival or reproduction. based on this information, the observed genetic changes mostly likely resulted from

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion

well, you see. the answer to your question is quite simple. the thing that is big, powerful, and over 9,000 is your mom.