ecosystems are not static. plants and animals are adle to adapt to changes in the physical environment. it is possible to predict changes. for example, when fire destroys the vegatation in a region, there will be certain changes. first grass and some flowers will grow. then insects will appear. the wind will blow the seeds of small trees. these trees will grow and birds will appear. as the trees grow, the grass will disappear and a dense forest will develop. some trees cannot live in a dense forest and will die. other trees will develop and a community of birds and animals will live in the forest.