What happens at the top of the food chain affects all the way down

which also ate the berries on the returning shrubs.Bison numbers rose as they browsed the revitalized forests.The wolves changed almost everything.This is an example of a trophic cascade,a change at the top of the food chain that tumbles all the way to the bottom,affecting every level.The discovery of widespread trophic cascades may be one of the most exciting scientific findings of the past half century.