Internal. The ultimate sources of variation, the source of new heritable characteristics in populations and species, are due to mutation and recombination in chromosomes, genes, DNA.
Zone VE is the flood insurance rate zone that corresponds to coastal areas that have additional hazards associated with storm waves. Mandatory flood insurance requirements apply. Zone X and Zone X-500 are flood insurance rate zones that are outside the flood plain or with average flood depths of less than 1 foot.
A Flood Zone is an area which has been carefully studied by the government to determine the probability of flooding due to intensive storms, or along the coast, severe tidal conditions. Flood Zones are designated to specify the probability and frequency of anticipated flood conditions. Flood zones range in severity.