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 AE is the flood insurance rate zone that corresponds with flood depths greater than 3 feet. Mandatory flood insurance purchase requirements apply. Zone AH is the flood insurance rate zone that corresponds to areas of shallow flooding with average depths between 1 and 3 feet.
On NFIP maps, the base floodplain is called the Special Flood Hazard. Area (SFHA). The SFHA is designated as Zone A, AE, A1-30, AO, AH, V, VE. or V1-30 depending on the amount of flood data available, the severity of the. flood hazard, or the age of the flood map (see the discussion of zones in this Unit.